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Re: '88 YJ 258 ci with carter Hard Warm Start
Mike Romain <romainm@sympatico.ca> wrote in message news:<3F83124C.E7063767@sympatico.ca>...
> Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > and see what happens. > > If it fires up, you have a hole in the gas line on the suction side of > the pump or a dead pump that is letting the gas backflow to the tank or > a torn diaphragm on the pump. The pump is brand new last month. > > Does the oil on the dipstick smell like gas? nope smells like SAE 30 > > Oh, the choke is an electric timer job. > > It will be totally closed after 5 minutes and opens according to how > long 12 volts has been going to it. Piece of crap actually because it > doesn't have a clue how hot or cold the engine really is, just how long > it has had 12 volts. I don't think the choke is the prime offender since I tend to wedge it open while trying to start it. > > Mike Well, I actually took the plug wrench with me on a day that it acted up. Which was totally out of the normal pattern because it was cold and rainy. It also didn't start right up this morning, which is atypical. It started a couple of times throughout the day, but when it came to going home time it would not start. The engine was still warm from having driven to the office from our pilot plant in the previous 45 minutes or so. I cranked and cranked. Pumped the gas a couple of times for giggles and cranked. No start. Aha! I have the plug wrench, pulled out old number 1 and Voila, the plug, much to my surprise was not wet. I could catch a faint whiff of petro when I put it to my nose, but that's it. I don't think that that's classic textbook flooded car "wet". So much for my theories to date. Not having a remote starter (my wife wasn't at work with me, and the cleaning lady had already gone home) I couldn't check if I had spark. I scratched my head for a while, cranked it once with the plug hanging over the alternator (not that I could even begin to see it from the driver's seat. I didn't have a screwdriver to jump my solenoid, just a 1/2" wrench and my socket driver which seemed like a bad idea on a rainy day). So I put the plug back in, crank it and doggone it if it doesn't start. Huh? Thankful (especially to Mike for encouraging me to verify if it was flooded) and confused, I drive home brainstorming new theories. What about if I had "weak spark"? I have checked the coil resistances and it's good, but what if my starter and solenoid are getting "worn" and sucking more juice than they should, that could drop the system voltage pretty low and without 11-12V, would the coil work right? I'm thinking about putting my spare battery in the passenger floor and wiring it directly into the coil to ensure it is seeing 12V. Whacked idea? Other suggestions? Like I've described, once the thing is started it runs fine, but when it's running, the alternator is keeping the coil at a happy 12-13V. |
Re: '88 YJ 258 ci with carter Hard Warm Start
Mike Romain <romainm@sympatico.ca> wrote in message news:<3F83124C.E7063767@sympatico.ca>...
> Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > and see what happens. > > If it fires up, you have a hole in the gas line on the suction side of > the pump or a dead pump that is letting the gas backflow to the tank or > a torn diaphragm on the pump. The pump is brand new last month. > > Does the oil on the dipstick smell like gas? nope smells like SAE 30 > > Oh, the choke is an electric timer job. > > It will be totally closed after 5 minutes and opens according to how > long 12 volts has been going to it. Piece of crap actually because it > doesn't have a clue how hot or cold the engine really is, just how long > it has had 12 volts. I don't think the choke is the prime offender since I tend to wedge it open while trying to start it. > > Mike Well, I actually took the plug wrench with me on a day that it acted up. Which was totally out of the normal pattern because it was cold and rainy. It also didn't start right up this morning, which is atypical. It started a couple of times throughout the day, but when it came to going home time it would not start. The engine was still warm from having driven to the office from our pilot plant in the previous 45 minutes or so. I cranked and cranked. Pumped the gas a couple of times for giggles and cranked. No start. Aha! I have the plug wrench, pulled out old number 1 and Voila, the plug, much to my surprise was not wet. I could catch a faint whiff of petro when I put it to my nose, but that's it. I don't think that that's classic textbook flooded car "wet". So much for my theories to date. Not having a remote starter (my wife wasn't at work with me, and the cleaning lady had already gone home) I couldn't check if I had spark. I scratched my head for a while, cranked it once with the plug hanging over the alternator (not that I could even begin to see it from the driver's seat. I didn't have a screwdriver to jump my solenoid, just a 1/2" wrench and my socket driver which seemed like a bad idea on a rainy day). So I put the plug back in, crank it and doggone it if it doesn't start. Huh? Thankful (especially to Mike for encouraging me to verify if it was flooded) and confused, I drive home brainstorming new theories. What about if I had "weak spark"? I have checked the coil resistances and it's good, but what if my starter and solenoid are getting "worn" and sucking more juice than they should, that could drop the system voltage pretty low and without 11-12V, would the coil work right? I'm thinking about putting my spare battery in the passenger floor and wiring it directly into the coil to ensure it is seeing 12V. Whacked idea? Other suggestions? Like I've described, once the thing is started it runs fine, but when it's running, the alternator is keeping the coil at a happy 12-13V. |
Re: '88 YJ 258 ci with carter Hard Warm Start
Try the shot of gas down the carb. Seriously.
That will tell you if it is a fuel delivery problem real fast. A dry plug sure implies no gas. Weak spark or no spark equals a wet plug 'really, really' fast! On my 258, I just need to loosen the nut on the top of the carb on top of the air filter. The air filter has a nice hollow there, so I can just trickle gas down there and it runs straight down the carb without taking the air filter off. I get one vroom, then it needs a second shot and sometimes a 3rd to pick up the gas if the line is empty. (out of gas, have a new fuel gauge and wiring with a warped sense of humor) Mike "averyislandboy@yahoo.com" wrote: > > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F83124C.E7063767@sympatico.ca>... > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > and see what happens. > > > > If it fires up, you have a hole in the gas line on the suction side of > > the pump or a dead pump that is letting the gas backflow to the tank or > > a torn diaphragm on the pump. > > The pump is brand new last month. > > > > > Does the oil on the dipstick smell like gas? > > nope smells like SAE 30 > > > > > Oh, the choke is an electric timer job. > > > > It will be totally closed after 5 minutes and opens according to how > > long 12 volts has been going to it. Piece of crap actually because it > > doesn't have a clue how hot or cold the engine really is, just how long > > it has had 12 volts. > > I don't think the choke is the prime offender since I tend to wedge it > open while trying to start it. > > > > > Mike > > Well, I actually took the plug wrench with me on a day that it acted > up. Which was totally out of the normal pattern because it was cold > and rainy. It also didn't start right up this morning, which is > atypical. It started a couple of times throughout the day, but when > it came to going home time it would not start. The engine was still > warm from having driven to the office from our pilot plant in the > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > couple of times for giggles and cranked. No start. Aha! I have the > plug wrench, pulled out old number 1 and Voila, the plug, much to my > surprise was not wet. I could catch a faint whiff of petro when I put > it to my nose, but that's it. I don't think that that's classic > textbook flooded car "wet". So much for my theories to date. Not > having a remote starter (my wife wasn't at work with me, and the > cleaning lady had already gone home) I couldn't check if I had spark. > I scratched my head for a while, cranked it once with the plug hanging > over the alternator (not that I could even begin to see it from the > driver's seat. I didn't have a screwdriver to jump my solenoid, just > a 1/2" wrench and my socket driver which seemed like a bad idea on a > rainy day). So I put the plug back in, crank it and doggone it if it > doesn't start. Huh? Thankful (especially to Mike for encouraging me > to verify if it was flooded) and confused, I drive home brainstorming > new theories. > > What about if I had "weak spark"? I have checked the coil resistances > and it's good, but what if my starter and solenoid are getting "worn" > and sucking more juice than they should, that could drop the system > voltage pretty low and without 11-12V, would the coil work right? I'm > thinking about putting my spare battery in the passenger floor and > wiring it directly into the coil to ensure it is seeing 12V. Whacked > idea? Other suggestions? Like I've described, once the thing is > started it runs fine, but when it's running, the alternator is keeping > the coil at a happy 12-13V. |
Re: '88 YJ 258 ci with carter Hard Warm Start
Try the shot of gas down the carb. Seriously.
That will tell you if it is a fuel delivery problem real fast. A dry plug sure implies no gas. Weak spark or no spark equals a wet plug 'really, really' fast! On my 258, I just need to loosen the nut on the top of the carb on top of the air filter. The air filter has a nice hollow there, so I can just trickle gas down there and it runs straight down the carb without taking the air filter off. I get one vroom, then it needs a second shot and sometimes a 3rd to pick up the gas if the line is empty. (out of gas, have a new fuel gauge and wiring with a warped sense of humor) Mike "averyislandboy@yahoo.com" wrote: > > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F83124C.E7063767@sympatico.ca>... > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > and see what happens. > > > > If it fires up, you have a hole in the gas line on the suction side of > > the pump or a dead pump that is letting the gas backflow to the tank or > > a torn diaphragm on the pump. > > The pump is brand new last month. > > > > > Does the oil on the dipstick smell like gas? > > nope smells like SAE 30 > > > > > Oh, the choke is an electric timer job. > > > > It will be totally closed after 5 minutes and opens according to how > > long 12 volts has been going to it. Piece of crap actually because it > > doesn't have a clue how hot or cold the engine really is, just how long > > it has had 12 volts. > > I don't think the choke is the prime offender since I tend to wedge it > open while trying to start it. > > > > > Mike > > Well, I actually took the plug wrench with me on a day that it acted > up. Which was totally out of the normal pattern because it was cold > and rainy. It also didn't start right up this morning, which is > atypical. It started a couple of times throughout the day, but when > it came to going home time it would not start. The engine was still > warm from having driven to the office from our pilot plant in the > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > couple of times for giggles and cranked. No start. Aha! I have the > plug wrench, pulled out old number 1 and Voila, the plug, much to my > surprise was not wet. I could catch a faint whiff of petro when I put > it to my nose, but that's it. I don't think that that's classic > textbook flooded car "wet". So much for my theories to date. Not > having a remote starter (my wife wasn't at work with me, and the > cleaning lady had already gone home) I couldn't check if I had spark. > I scratched my head for a while, cranked it once with the plug hanging > over the alternator (not that I could even begin to see it from the > driver's seat. I didn't have a screwdriver to jump my solenoid, just > a 1/2" wrench and my socket driver which seemed like a bad idea on a > rainy day). So I put the plug back in, crank it and doggone it if it > doesn't start. Huh? Thankful (especially to Mike for encouraging me > to verify if it was flooded) and confused, I drive home brainstorming > new theories. > > What about if I had "weak spark"? I have checked the coil resistances > and it's good, but what if my starter and solenoid are getting "worn" > and sucking more juice than they should, that could drop the system > voltage pretty low and without 11-12V, would the coil work right? I'm > thinking about putting my spare battery in the passenger floor and > wiring it directly into the coil to ensure it is seeing 12V. Whacked > idea? Other suggestions? Like I've described, once the thing is > started it runs fine, but when it's running, the alternator is keeping > the coil at a happy 12-13V. |
Re: '88 YJ 258 ci with carter Hard Warm Start
Try the shot of gas down the carb. Seriously.
That will tell you if it is a fuel delivery problem real fast. A dry plug sure implies no gas. Weak spark or no spark equals a wet plug 'really, really' fast! On my 258, I just need to loosen the nut on the top of the carb on top of the air filter. The air filter has a nice hollow there, so I can just trickle gas down there and it runs straight down the carb without taking the air filter off. I get one vroom, then it needs a second shot and sometimes a 3rd to pick up the gas if the line is empty. (out of gas, have a new fuel gauge and wiring with a warped sense of humor) Mike "averyislandboy@yahoo.com" wrote: > > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F83124C.E7063767@sympatico.ca>... > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > and see what happens. > > > > If it fires up, you have a hole in the gas line on the suction side of > > the pump or a dead pump that is letting the gas backflow to the tank or > > a torn diaphragm on the pump. > > The pump is brand new last month. > > > > > Does the oil on the dipstick smell like gas? > > nope smells like SAE 30 > > > > > Oh, the choke is an electric timer job. > > > > It will be totally closed after 5 minutes and opens according to how > > long 12 volts has been going to it. Piece of crap actually because it > > doesn't have a clue how hot or cold the engine really is, just how long > > it has had 12 volts. > > I don't think the choke is the prime offender since I tend to wedge it > open while trying to start it. > > > > > Mike > > Well, I actually took the plug wrench with me on a day that it acted > up. Which was totally out of the normal pattern because it was cold > and rainy. It also didn't start right up this morning, which is > atypical. It started a couple of times throughout the day, but when > it came to going home time it would not start. The engine was still > warm from having driven to the office from our pilot plant in the > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > couple of times for giggles and cranked. No start. Aha! I have the > plug wrench, pulled out old number 1 and Voila, the plug, much to my > surprise was not wet. I could catch a faint whiff of petro when I put > it to my nose, but that's it. I don't think that that's classic > textbook flooded car "wet". So much for my theories to date. Not > having a remote starter (my wife wasn't at work with me, and the > cleaning lady had already gone home) I couldn't check if I had spark. > I scratched my head for a while, cranked it once with the plug hanging > over the alternator (not that I could even begin to see it from the > driver's seat. I didn't have a screwdriver to jump my solenoid, just > a 1/2" wrench and my socket driver which seemed like a bad idea on a > rainy day). So I put the plug back in, crank it and doggone it if it > doesn't start. Huh? Thankful (especially to Mike for encouraging me > to verify if it was flooded) and confused, I drive home brainstorming > new theories. > > What about if I had "weak spark"? I have checked the coil resistances > and it's good, but what if my starter and solenoid are getting "worn" > and sucking more juice than they should, that could drop the system > voltage pretty low and without 11-12V, would the coil work right? I'm > thinking about putting my spare battery in the passenger floor and > wiring it directly into the coil to ensure it is seeing 12V. Whacked > idea? Other suggestions? Like I've described, once the thing is > started it runs fine, but when it's running, the alternator is keeping > the coil at a happy 12-13V. |
Re: '88 YJ 258 ci with carter Hard Warm Start
"Mike Romain" <romainm@sympatico.ca> wrote in message news:3F8412D6.9744B29E@sympatico.ca... > I have a buddy that learned all about those starter remotes the hard > way. He was turning it over and it started unexpectedly. SOP is to pull the coil wire and jumper it to ground... don't mess with one if you don't know what you're doing. __ Steve ps sorry about your buddy... |
Re: '88 YJ 258 ci with carter Hard Warm Start
"Mike Romain" <romainm@sympatico.ca> wrote in message news:3F8412D6.9744B29E@sympatico.ca... > I have a buddy that learned all about those starter remotes the hard > way. He was turning it over and it started unexpectedly. SOP is to pull the coil wire and jumper it to ground... don't mess with one if you don't know what you're doing. __ Steve ps sorry about your buddy... |
Re: '88 YJ 258 ci with carter Hard Warm Start
"Mike Romain" <romainm@sympatico.ca> wrote in message news:3F8412D6.9744B29E@sympatico.ca... > I have a buddy that learned all about those starter remotes the hard > way. He was turning it over and it started unexpectedly. SOP is to pull the coil wire and jumper it to ground... don't mess with one if you don't know what you're doing. __ Steve ps sorry about your buddy... |
Re: '88 YJ 258 ci with carter Hard Warm Start
Stephen Cowell wrote:
> > "Mike Romain" <romainm@sympatico.ca> wrote in message > news:3F8412D6.9744B29E@sympatico.ca... > > I have a buddy that learned all about those starter remotes the hard > > way. He was turning it over and it started unexpectedly. > > SOP is to pull the coil wire and jumper it to ground... don't > mess with one if you don't know what you're doing. > __ > Steve > > ps sorry about your buddy... He wasn't 'thinking' or expecting it to fire up because it was dead and he wasn't careful! It happened 15 years ago and now he needs the second hip. He still gets teased about it because he is a 'Newfie' from Newfoundland. Most countries have their area jokes and in Canada they are 'Newfie' jokes. I mean, it would take a 'Newfie' to run himself down with his own car, eh... ;-) He did do a good thing though, I now make double sure no one is in front of anything that cranks over for any reason and have seen a couple jump forward.... I also am around a lot of driveway repairs with lots of 'spectators'. Never stand in front of anything when the starter fires! Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's |
Re: '88 YJ 258 ci with carter Hard Warm Start
Stephen Cowell wrote:
> > "Mike Romain" <romainm@sympatico.ca> wrote in message > news:3F8412D6.9744B29E@sympatico.ca... > > I have a buddy that learned all about those starter remotes the hard > > way. He was turning it over and it started unexpectedly. > > SOP is to pull the coil wire and jumper it to ground... don't > mess with one if you don't know what you're doing. > __ > Steve > > ps sorry about your buddy... He wasn't 'thinking' or expecting it to fire up because it was dead and he wasn't careful! It happened 15 years ago and now he needs the second hip. He still gets teased about it because he is a 'Newfie' from Newfoundland. Most countries have their area jokes and in Canada they are 'Newfie' jokes. I mean, it would take a 'Newfie' to run himself down with his own car, eh... ;-) He did do a good thing though, I now make double sure no one is in front of anything that cranks over for any reason and have seen a couple jump forward.... I also am around a lot of driveway repairs with lots of 'spectators'. Never stand in front of anything when the starter fires! Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's |
Re: '88 YJ 258 ci with carter Hard Warm Start
Stephen Cowell wrote:
> > "Mike Romain" <romainm@sympatico.ca> wrote in message > news:3F8412D6.9744B29E@sympatico.ca... > > I have a buddy that learned all about those starter remotes the hard > > way. He was turning it over and it started unexpectedly. > > SOP is to pull the coil wire and jumper it to ground... don't > mess with one if you don't know what you're doing. > __ > Steve > > ps sorry about your buddy... He wasn't 'thinking' or expecting it to fire up because it was dead and he wasn't careful! It happened 15 years ago and now he needs the second hip. He still gets teased about it because he is a 'Newfie' from Newfoundland. Most countries have their area jokes and in Canada they are 'Newfie' jokes. I mean, it would take a 'Newfie' to run himself down with his own car, eh... ;-) He did do a good thing though, I now make double sure no one is in front of anything that cranks over for any reason and have seen a couple jump forward.... I also am around a lot of driveway repairs with lots of 'spectators'. Never stand in front of anything when the starter fires! Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's |
Re: '88 YJ 258 ci with carter Hard Warm Start
<averyislandboy@yahoo.com> wrote in message news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F83124C.E7063767@sympatico.ca>... > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > and see what happens. > > > > If it fires up, you have a hole in the gas line on the suction side of > > the pump or a dead pump that is letting the gas backflow to the tank or > > a torn diaphragm on the pump. > > The pump is brand new last month. > > > > > Does the oil on the dipstick smell like gas? > > nope smells like SAE 30 > > > > > Oh, the choke is an electric timer job. > > > > It will be totally closed after 5 minutes and opens according to how > > long 12 volts has been going to it. Piece of crap actually because it > > doesn't have a clue how hot or cold the engine really is, just how long > > it has had 12 volts. > > I don't think the choke is the prime offender since I tend to wedge it > open while trying to start it. > > > > > Mike > > Well, I actually took the plug wrench with me on a day that it acted > up. Which was totally out of the normal pattern because it was cold > and rainy. It also didn't start right up this morning, which is > atypical. It started a couple of times throughout the day, but when > it came to going home time it would not start. The engine was still > warm from having driven to the office from our pilot plant in the > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > couple of times for giggles and cranked. No start. Aha! I have the > plug wrench, pulled out old number 1 and Voila, the plug, much to my > surprise was not wet. I could catch a faint whiff of petro when I put > it to my nose, but that's it. I don't think that that's classic > textbook flooded car "wet". So much for my theories to date. Not > having a remote starter (my wife wasn't at work with me, and the > cleaning lady had already gone home) I couldn't check if I had spark. > I scratched my head for a while, cranked it once with the plug hanging > over the alternator (not that I could even begin to see it from the > driver's seat. I didn't have a screwdriver to jump my solenoid, just > a 1/2" wrench and my socket driver which seemed like a bad idea on a > rainy day). So I put the plug back in, crank it and doggone it if it > doesn't start. Huh? Thankful (especially to Mike for encouraging me > to verify if it was flooded) and confused, I drive home brainstorming > new theories. > > What about if I had "weak spark"? I have checked the coil resistances > and it's good, but what if my starter and solenoid are getting "worn" > and sucking more juice than they should, that could drop the system > voltage pretty low and without 11-12V, would the coil work right? I'm > thinking about putting my spare battery in the passenger floor and > wiring it directly into the coil to ensure it is seeing 12V. Whacked > idea? Other suggestions? Like I've described, once the thing is > started it runs fine, but when it's running, the alternator is keeping > the coil at a happy 12-13V. OK, I might have a couple ideas here based on all the things I've read in this thread. First off, all of this is based on memory from what I've read, so bear with me if I repeat something you've tried. I remember you saying that when you pumped the accelerator after sitting, that the pump shot was good for a couple shots and then it "went dry". This seems wrong to me. You should get quite a few shots before the float bowl empties out. Definitely more than 2 or 3. This leads me to believe that either the float level is way too low, or possibly the fuel in the bowl is vaporizing from percolation, or both. A carb has more tendency to percolate when the float level is low because in essence the fuel cools the carburetor to some extent. Fuel percolation can also cause both flooded conditions and no fuel conditions, depending on how long the vehicle sits between starts. The fuel can sometimes percolate until the bowl is empty. The percolation can cause the fuel to siphon itself out of the carb through the fuel passages and into the engine. Also, regarding the fuel pump, just because it is new doesn't mean it is working properly. Try checking both volume and pressure. I'm not sure of the volume specs for your pump, but most of them are usually about a pint in 20-30 seconds of cranking. You'll have to check a service manual for your specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike said, also check all of your fuel lines for pinholes. If the pump is sucking air instead of fuel, this can also lead to the percolation condition. The volume tests should reveal a suction problem as well. You may want to check the fuel you've been using. Maybe your gas station got some bad gas, or possibly they have mixed in that reconstituted crap. Some vehicles just flat won't run right on that stuff. As far as the spark being weak, I would say possible but not likely. Most factory coils "amplify" the voltage by a factor of about 1600 or more, which means that even with 8 volts going to the coil, you would have over 12000 volts going to the plugs. While this is not optimum, it will definitely fire a plug enough to start the engine. Remember, a lot of the old point systems had a ballast resistor in the ignition circuit to intentionally cut the voltage back while cranking. Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
<averyislandboy@yahoo.com> wrote in message news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F83124C.E7063767@sympatico.ca>... > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > and see what happens. > > > > If it fires up, you have a hole in the gas line on the suction side of > > the pump or a dead pump that is letting the gas backflow to the tank or > > a torn diaphragm on the pump. > > The pump is brand new last month. > > > > > Does the oil on the dipstick smell like gas? > > nope smells like SAE 30 > > > > > Oh, the choke is an electric timer job. > > > > It will be totally closed after 5 minutes and opens according to how > > long 12 volts has been going to it. Piece of crap actually because it > > doesn't have a clue how hot or cold the engine really is, just how long > > it has had 12 volts. > > I don't think the choke is the prime offender since I tend to wedge it > open while trying to start it. > > > > > Mike > > Well, I actually took the plug wrench with me on a day that it acted > up. Which was totally out of the normal pattern because it was cold > and rainy. It also didn't start right up this morning, which is > atypical. It started a couple of times throughout the day, but when > it came to going home time it would not start. The engine was still > warm from having driven to the office from our pilot plant in the > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > couple of times for giggles and cranked. No start. Aha! I have the > plug wrench, pulled out old number 1 and Voila, the plug, much to my > surprise was not wet. I could catch a faint whiff of petro when I put > it to my nose, but that's it. I don't think that that's classic > textbook flooded car "wet". So much for my theories to date. Not > having a remote starter (my wife wasn't at work with me, and the > cleaning lady had already gone home) I couldn't check if I had spark. > I scratched my head for a while, cranked it once with the plug hanging > over the alternator (not that I could even begin to see it from the > driver's seat. I didn't have a screwdriver to jump my solenoid, just > a 1/2" wrench and my socket driver which seemed like a bad idea on a > rainy day). So I put the plug back in, crank it and doggone it if it > doesn't start. Huh? Thankful (especially to Mike for encouraging me > to verify if it was flooded) and confused, I drive home brainstorming > new theories. > > What about if I had "weak spark"? I have checked the coil resistances > and it's good, but what if my starter and solenoid are getting "worn" > and sucking more juice than they should, that could drop the system > voltage pretty low and without 11-12V, would the coil work right? I'm > thinking about putting my spare battery in the passenger floor and > wiring it directly into the coil to ensure it is seeing 12V. Whacked > idea? Other suggestions? Like I've described, once the thing is > started it runs fine, but when it's running, the alternator is keeping > the coil at a happy 12-13V. OK, I might have a couple ideas here based on all the things I've read in this thread. First off, all of this is based on memory from what I've read, so bear with me if I repeat something you've tried. I remember you saying that when you pumped the accelerator after sitting, that the pump shot was good for a couple shots and then it "went dry". This seems wrong to me. You should get quite a few shots before the float bowl empties out. Definitely more than 2 or 3. This leads me to believe that either the float level is way too low, or possibly the fuel in the bowl is vaporizing from percolation, or both. A carb has more tendency to percolate when the float level is low because in essence the fuel cools the carburetor to some extent. Fuel percolation can also cause both flooded conditions and no fuel conditions, depending on how long the vehicle sits between starts. The fuel can sometimes percolate until the bowl is empty. The percolation can cause the fuel to siphon itself out of the carb through the fuel passages and into the engine. Also, regarding the fuel pump, just because it is new doesn't mean it is working properly. Try checking both volume and pressure. I'm not sure of the volume specs for your pump, but most of them are usually about a pint in 20-30 seconds of cranking. You'll have to check a service manual for your specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike said, also check all of your fuel lines for pinholes. If the pump is sucking air instead of fuel, this can also lead to the percolation condition. The volume tests should reveal a suction problem as well. You may want to check the fuel you've been using. Maybe your gas station got some bad gas, or possibly they have mixed in that reconstituted crap. Some vehicles just flat won't run right on that stuff. As far as the spark being weak, I would say possible but not likely. Most factory coils "amplify" the voltage by a factor of about 1600 or more, which means that even with 8 volts going to the coil, you would have over 12000 volts going to the plugs. While this is not optimum, it will definitely fire a plug enough to start the engine. Remember, a lot of the old point systems had a ballast resistor in the ignition circuit to intentionally cut the voltage back while cranking. Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
<averyislandboy@yahoo.com> wrote in message news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F83124C.E7063767@sympatico.ca>... > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > and see what happens. > > > > If it fires up, you have a hole in the gas line on the suction side of > > the pump or a dead pump that is letting the gas backflow to the tank or > > a torn diaphragm on the pump. > > The pump is brand new last month. > > > > > Does the oil on the dipstick smell like gas? > > nope smells like SAE 30 > > > > > Oh, the choke is an electric timer job. > > > > It will be totally closed after 5 minutes and opens according to how > > long 12 volts has been going to it. Piece of crap actually because it > > doesn't have a clue how hot or cold the engine really is, just how long > > it has had 12 volts. > > I don't think the choke is the prime offender since I tend to wedge it > open while trying to start it. > > > > > Mike > > Well, I actually took the plug wrench with me on a day that it acted > up. Which was totally out of the normal pattern because it was cold > and rainy. It also didn't start right up this morning, which is > atypical. It started a couple of times throughout the day, but when > it came to going home time it would not start. The engine was still > warm from having driven to the office from our pilot plant in the > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > couple of times for giggles and cranked. No start. Aha! I have the > plug wrench, pulled out old number 1 and Voila, the plug, much to my > surprise was not wet. I could catch a faint whiff of petro when I put > it to my nose, but that's it. I don't think that that's classic > textbook flooded car "wet". So much for my theories to date. Not > having a remote starter (my wife wasn't at work with me, and the > cleaning lady had already gone home) I couldn't check if I had spark. > I scratched my head for a while, cranked it once with the plug hanging > over the alternator (not that I could even begin to see it from the > driver's seat. I didn't have a screwdriver to jump my solenoid, just > a 1/2" wrench and my socket driver which seemed like a bad idea on a > rainy day). So I put the plug back in, crank it and doggone it if it > doesn't start. Huh? Thankful (especially to Mike for encouraging me > to verify if it was flooded) and confused, I drive home brainstorming > new theories. > > What about if I had "weak spark"? I have checked the coil resistances > and it's good, but what if my starter and solenoid are getting "worn" > and sucking more juice than they should, that could drop the system > voltage pretty low and without 11-12V, would the coil work right? I'm > thinking about putting my spare battery in the passenger floor and > wiring it directly into the coil to ensure it is seeing 12V. Whacked > idea? Other suggestions? Like I've described, once the thing is > started it runs fine, but when it's running, the alternator is keeping > the coil at a happy 12-13V. OK, I might have a couple ideas here based on all the things I've read in this thread. First off, all of this is based on memory from what I've read, so bear with me if I repeat something you've tried. I remember you saying that when you pumped the accelerator after sitting, that the pump shot was good for a couple shots and then it "went dry". This seems wrong to me. You should get quite a few shots before the float bowl empties out. Definitely more than 2 or 3. This leads me to believe that either the float level is way too low, or possibly the fuel in the bowl is vaporizing from percolation, or both. A carb has more tendency to percolate when the float level is low because in essence the fuel cools the carburetor to some extent. Fuel percolation can also cause both flooded conditions and no fuel conditions, depending on how long the vehicle sits between starts. The fuel can sometimes percolate until the bowl is empty. The percolation can cause the fuel to siphon itself out of the carb through the fuel passages and into the engine. Also, regarding the fuel pump, just because it is new doesn't mean it is working properly. Try checking both volume and pressure. I'm not sure of the volume specs for your pump, but most of them are usually about a pint in 20-30 seconds of cranking. You'll have to check a service manual for your specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike said, also check all of your fuel lines for pinholes. If the pump is sucking air instead of fuel, this can also lead to the percolation condition. The volume tests should reveal a suction problem as well. You may want to check the fuel you've been using. Maybe your gas station got some bad gas, or possibly they have mixed in that reconstituted crap. Some vehicles just flat won't run right on that stuff. As far as the spark being weak, I would say possible but not likely. Most factory coils "amplify" the voltage by a factor of about 1600 or more, which means that even with 8 volts going to the coil, you would have over 12000 volts going to the plugs. While this is not optimum, it will definitely fire a plug enough to start the engine. Remember, a lot of the old point systems had a ballast resistor in the ignition circuit to intentionally cut the voltage back while cranking. Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Just a couple comments.
A vapor or percolation lock will shut down a carb. If there isn't fuel pushing, the couple squirts you can get out of the accelerator pump won't start the engine. They just give a dry spark plug with a slight gas smell. And the ballast resistor is to give it 9 or so volts when running, the solenoid to coil tag gives battery power in a start, which is down below 12 usually with the starter sucking on it. It being still hot and dying is weird, but a shot of gas down the carb will tell all. Likely a rubber hose between the tank and frame or frame and engine has a crack, so sometimes it air locks fast, sometimes slow depending on the angle it stopped at. Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's c wrote: > > <averyislandboy@yahoo.com> wrote in message > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F83124C.E7063767@sympatico.ca>... > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > and see what happens. > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > a torn diaphragm on the pump. > > > > The pump is brand new last month. > > > > > > > > Does the oil on the dipstick smell like gas? > > > > nope smells like SAE 30 > > > > > > > > Oh, the choke is an electric timer job. > > > > > > It will be totally closed after 5 minutes and opens according to how > > > long 12 volts has been going to it. Piece of crap actually because it > > > doesn't have a clue how hot or cold the engine really is, just how long > > > it has had 12 volts. > > > > I don't think the choke is the prime offender since I tend to wedge it > > open while trying to start it. > > > > > > > > Mike > > > > Well, I actually took the plug wrench with me on a day that it acted > > up. Which was totally out of the normal pattern because it was cold > > and rainy. It also didn't start right up this morning, which is > > atypical. It started a couple of times throughout the day, but when > > it came to going home time it would not start. The engine was still > > warm from having driven to the office from our pilot plant in the > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > couple of times for giggles and cranked. No start. Aha! I have the > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > surprise was not wet. I could catch a faint whiff of petro when I put > > it to my nose, but that's it. I don't think that that's classic > > textbook flooded car "wet". So much for my theories to date. Not > > having a remote starter (my wife wasn't at work with me, and the > > cleaning lady had already gone home) I couldn't check if I had spark. > > I scratched my head for a while, cranked it once with the plug hanging > > over the alternator (not that I could even begin to see it from the > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > rainy day). So I put the plug back in, crank it and doggone it if it > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > to verify if it was flooded) and confused, I drive home brainstorming > > new theories. > > > > What about if I had "weak spark"? I have checked the coil resistances > > and it's good, but what if my starter and solenoid are getting "worn" > > and sucking more juice than they should, that could drop the system > > voltage pretty low and without 11-12V, would the coil work right? I'm > > thinking about putting my spare battery in the passenger floor and > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > idea? Other suggestions? Like I've described, once the thing is > > started it runs fine, but when it's running, the alternator is keeping > > the coil at a happy 12-13V. > > OK, I might have a couple ideas here based on all the things I've read in > this thread. First off, all of this is based on memory from what I've read, > so bear with me if I repeat something you've tried. I remember you saying > that when you pumped the accelerator after sitting, that the pump shot was > good for a couple shots and then it "went dry". This seems wrong to me. You > should get quite a few shots before the float bowl empties out. Definitely > more than 2 or 3. This leads me to believe that either the float level is > way too low, or possibly the fuel in the bowl is vaporizing from > percolation, or both. A carb has more tendency to percolate when the float > level is low because in essence the fuel cools the carburetor to some > extent. Fuel percolation can also cause both flooded conditions and no fuel > conditions, depending on how long the vehicle sits between starts. The fuel > can sometimes percolate until the bowl is empty. The percolation can cause > the fuel to siphon itself out of the carb through the fuel passages and into > the engine. > > Also, regarding the fuel pump, just because it is new doesn't mean it is > working properly. Try checking both volume and pressure. I'm not sure of the > volume specs for your pump, but most of them are usually about a pint in > 20-30 seconds of cranking. You'll have to check a service manual for your > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > said, also check all of your fuel lines for pinholes. If the pump is sucking > air instead of fuel, this can also lead to the percolation condition. The > volume tests should reveal a suction problem as well. > > You may want to check the fuel you've been using. Maybe your gas station got > some bad gas, or possibly they have mixed in that reconstituted crap. Some > vehicles just flat won't run right on that stuff. > > As far as the spark being weak, I would say possible but not likely. Most > factory coils "amplify" the voltage by a factor of about 1600 or more, which > means that even with 8 volts going to the coil, you would have over 12000 > volts going to the plugs. While this is not optimum, it will definitely fire > a plug enough to start the engine. Remember, a lot of the old point systems > had a ballast resistor in the ignition circuit to intentionally cut the > voltage back while cranking. > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Just a couple comments.
A vapor or percolation lock will shut down a carb. If there isn't fuel pushing, the couple squirts you can get out of the accelerator pump won't start the engine. They just give a dry spark plug with a slight gas smell. And the ballast resistor is to give it 9 or so volts when running, the solenoid to coil tag gives battery power in a start, which is down below 12 usually with the starter sucking on it. It being still hot and dying is weird, but a shot of gas down the carb will tell all. Likely a rubber hose between the tank and frame or frame and engine has a crack, so sometimes it air locks fast, sometimes slow depending on the angle it stopped at. Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's c wrote: > > <averyislandboy@yahoo.com> wrote in message > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F83124C.E7063767@sympatico.ca>... > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > and see what happens. > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > a torn diaphragm on the pump. > > > > The pump is brand new last month. > > > > > > > > Does the oil on the dipstick smell like gas? > > > > nope smells like SAE 30 > > > > > > > > Oh, the choke is an electric timer job. > > > > > > It will be totally closed after 5 minutes and opens according to how > > > long 12 volts has been going to it. Piece of crap actually because it > > > doesn't have a clue how hot or cold the engine really is, just how long > > > it has had 12 volts. > > > > I don't think the choke is the prime offender since I tend to wedge it > > open while trying to start it. > > > > > > > > Mike > > > > Well, I actually took the plug wrench with me on a day that it acted > > up. Which was totally out of the normal pattern because it was cold > > and rainy. It also didn't start right up this morning, which is > > atypical. It started a couple of times throughout the day, but when > > it came to going home time it would not start. The engine was still > > warm from having driven to the office from our pilot plant in the > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > couple of times for giggles and cranked. No start. Aha! I have the > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > surprise was not wet. I could catch a faint whiff of petro when I put > > it to my nose, but that's it. I don't think that that's classic > > textbook flooded car "wet". So much for my theories to date. Not > > having a remote starter (my wife wasn't at work with me, and the > > cleaning lady had already gone home) I couldn't check if I had spark. > > I scratched my head for a while, cranked it once with the plug hanging > > over the alternator (not that I could even begin to see it from the > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > rainy day). So I put the plug back in, crank it and doggone it if it > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > to verify if it was flooded) and confused, I drive home brainstorming > > new theories. > > > > What about if I had "weak spark"? I have checked the coil resistances > > and it's good, but what if my starter and solenoid are getting "worn" > > and sucking more juice than they should, that could drop the system > > voltage pretty low and without 11-12V, would the coil work right? I'm > > thinking about putting my spare battery in the passenger floor and > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > idea? Other suggestions? Like I've described, once the thing is > > started it runs fine, but when it's running, the alternator is keeping > > the coil at a happy 12-13V. > > OK, I might have a couple ideas here based on all the things I've read in > this thread. First off, all of this is based on memory from what I've read, > so bear with me if I repeat something you've tried. I remember you saying > that when you pumped the accelerator after sitting, that the pump shot was > good for a couple shots and then it "went dry". This seems wrong to me. You > should get quite a few shots before the float bowl empties out. Definitely > more than 2 or 3. This leads me to believe that either the float level is > way too low, or possibly the fuel in the bowl is vaporizing from > percolation, or both. A carb has more tendency to percolate when the float > level is low because in essence the fuel cools the carburetor to some > extent. Fuel percolation can also cause both flooded conditions and no fuel > conditions, depending on how long the vehicle sits between starts. The fuel > can sometimes percolate until the bowl is empty. The percolation can cause > the fuel to siphon itself out of the carb through the fuel passages and into > the engine. > > Also, regarding the fuel pump, just because it is new doesn't mean it is > working properly. Try checking both volume and pressure. I'm not sure of the > volume specs for your pump, but most of them are usually about a pint in > 20-30 seconds of cranking. You'll have to check a service manual for your > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > said, also check all of your fuel lines for pinholes. If the pump is sucking > air instead of fuel, this can also lead to the percolation condition. The > volume tests should reveal a suction problem as well. > > You may want to check the fuel you've been using. Maybe your gas station got > some bad gas, or possibly they have mixed in that reconstituted crap. Some > vehicles just flat won't run right on that stuff. > > As far as the spark being weak, I would say possible but not likely. Most > factory coils "amplify" the voltage by a factor of about 1600 or more, which > means that even with 8 volts going to the coil, you would have over 12000 > volts going to the plugs. While this is not optimum, it will definitely fire > a plug enough to start the engine. Remember, a lot of the old point systems > had a ballast resistor in the ignition circuit to intentionally cut the > voltage back while cranking. > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Just a couple comments.
A vapor or percolation lock will shut down a carb. If there isn't fuel pushing, the couple squirts you can get out of the accelerator pump won't start the engine. They just give a dry spark plug with a slight gas smell. And the ballast resistor is to give it 9 or so volts when running, the solenoid to coil tag gives battery power in a start, which is down below 12 usually with the starter sucking on it. It being still hot and dying is weird, but a shot of gas down the carb will tell all. Likely a rubber hose between the tank and frame or frame and engine has a crack, so sometimes it air locks fast, sometimes slow depending on the angle it stopped at. Mike 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 88 Cherokee 235 BFG AT's c wrote: > > <averyislandboy@yahoo.com> wrote in message > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F83124C.E7063767@sympatico.ca>... > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > and see what happens. > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > a torn diaphragm on the pump. > > > > The pump is brand new last month. > > > > > > > > Does the oil on the dipstick smell like gas? > > > > nope smells like SAE 30 > > > > > > > > Oh, the choke is an electric timer job. > > > > > > It will be totally closed after 5 minutes and opens according to how > > > long 12 volts has been going to it. Piece of crap actually because it > > > doesn't have a clue how hot or cold the engine really is, just how long > > > it has had 12 volts. > > > > I don't think the choke is the prime offender since I tend to wedge it > > open while trying to start it. > > > > > > > > Mike > > > > Well, I actually took the plug wrench with me on a day that it acted > > up. Which was totally out of the normal pattern because it was cold > > and rainy. It also didn't start right up this morning, which is > > atypical. It started a couple of times throughout the day, but when > > it came to going home time it would not start. The engine was still > > warm from having driven to the office from our pilot plant in the > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > couple of times for giggles and cranked. No start. Aha! I have the > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > surprise was not wet. I could catch a faint whiff of petro when I put > > it to my nose, but that's it. I don't think that that's classic > > textbook flooded car "wet". So much for my theories to date. Not > > having a remote starter (my wife wasn't at work with me, and the > > cleaning lady had already gone home) I couldn't check if I had spark. > > I scratched my head for a while, cranked it once with the plug hanging > > over the alternator (not that I could even begin to see it from the > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > rainy day). So I put the plug back in, crank it and doggone it if it > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > to verify if it was flooded) and confused, I drive home brainstorming > > new theories. > > > > What about if I had "weak spark"? I have checked the coil resistances > > and it's good, but what if my starter and solenoid are getting "worn" > > and sucking more juice than they should, that could drop the system > > voltage pretty low and without 11-12V, would the coil work right? I'm > > thinking about putting my spare battery in the passenger floor and > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > idea? Other suggestions? Like I've described, once the thing is > > started it runs fine, but when it's running, the alternator is keeping > > the coil at a happy 12-13V. > > OK, I might have a couple ideas here based on all the things I've read in > this thread. First off, all of this is based on memory from what I've read, > so bear with me if I repeat something you've tried. I remember you saying > that when you pumped the accelerator after sitting, that the pump shot was > good for a couple shots and then it "went dry". This seems wrong to me. You > should get quite a few shots before the float bowl empties out. Definitely > more than 2 or 3. This leads me to believe that either the float level is > way too low, or possibly the fuel in the bowl is vaporizing from > percolation, or both. A carb has more tendency to percolate when the float > level is low because in essence the fuel cools the carburetor to some > extent. Fuel percolation can also cause both flooded conditions and no fuel > conditions, depending on how long the vehicle sits between starts. The fuel > can sometimes percolate until the bowl is empty. The percolation can cause > the fuel to siphon itself out of the carb through the fuel passages and into > the engine. > > Also, regarding the fuel pump, just because it is new doesn't mean it is > working properly. Try checking both volume and pressure. I'm not sure of the > volume specs for your pump, but most of them are usually about a pint in > 20-30 seconds of cranking. You'll have to check a service manual for your > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > said, also check all of your fuel lines for pinholes. If the pump is sucking > air instead of fuel, this can also lead to the percolation condition. The > volume tests should reveal a suction problem as well. > > You may want to check the fuel you've been using. Maybe your gas station got > some bad gas, or possibly they have mixed in that reconstituted crap. Some > vehicles just flat won't run right on that stuff. > > As far as the spark being weak, I would say possible but not likely. Most > factory coils "amplify" the voltage by a factor of about 1600 or more, which > means that even with 8 volts going to the coil, you would have over 12000 > volts going to the plugs. While this is not optimum, it will definitely fire > a plug enough to start the engine. Remember, a lot of the old point systems > had a ballast resistor in the ignition circuit to intentionally cut the > voltage back while cranking. > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
More than likely you are right Mike. I am just trying to give him other
possibilities to check on. I really believe it is a fuel issue one way or another. Chris "Mike Romain" <romainm@sympatico.ca> wrote in message news:3F84C160.BEFBACD6@sympatico.ca... > Just a couple comments. > > A vapor or percolation lock will shut down a carb. If there isn't fuel > pushing, the couple squirts you can get out of the accelerator pump > won't start the engine. They just give a dry spark plug with a slight > gas smell. > > And the ballast resistor is to give it 9 or so volts when running, the > solenoid to coil tag gives battery power in a start, which is down below > 12 usually with the starter sucking on it. > > It being still hot and dying is weird, but a shot of gas down the carb > will tell all. Likely a rubber hose between the tank and frame or frame > and engine has a crack, so sometimes it air locks fast, sometimes slow > depending on the angle it stopped at. > > Mike > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > 88 Cherokee 235 BFG AT's > > c wrote: > > > > <averyislandboy@yahoo.com> wrote in message > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > Mike Romain <romainm@sympatico.ca> wrote in message > > news:<3F83124C.E7063767@sympatico.ca>... > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > and see what happens. > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > a torn diaphragm on the pump. > > > > > > The pump is brand new last month. > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > nope smells like SAE 30 > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > it has had 12 volts. > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > open while trying to start it. > > > > > > > > > > > Mike > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > up. Which was totally out of the normal pattern because it was cold > > > and rainy. It also didn't start right up this morning, which is > > > atypical. It started a couple of times throughout the day, but when > > > it came to going home time it would not start. The engine was still > > > warm from having driven to the office from our pilot plant in the > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > couple of times for giggles and cranked. No start. Aha! I have the > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > it to my nose, but that's it. I don't think that that's classic > > > textbook flooded car "wet". So much for my theories to date. Not > > > having a remote starter (my wife wasn't at work with me, and the > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > I scratched my head for a while, cranked it once with the plug hanging > > > over the alternator (not that I could even begin to see it from the > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > to verify if it was flooded) and confused, I drive home brainstorming > > > new theories. > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > and it's good, but what if my starter and solenoid are getting "worn" > > > and sucking more juice than they should, that could drop the system > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > thinking about putting my spare battery in the passenger floor and > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > idea? Other suggestions? Like I've described, once the thing is > > > started it runs fine, but when it's running, the alternator is keeping > > > the coil at a happy 12-13V. > > > > OK, I might have a couple ideas here based on all the things I've read in > > this thread. First off, all of this is based on memory from what I've read, > > so bear with me if I repeat something you've tried. I remember you saying > > that when you pumped the accelerator after sitting, that the pump shot was > > good for a couple shots and then it "went dry". This seems wrong to me. You > > should get quite a few shots before the float bowl empties out. Definitely > > more than 2 or 3. This leads me to believe that either the float level is > > way too low, or possibly the fuel in the bowl is vaporizing from > > percolation, or both. A carb has more tendency to percolate when the float > > level is low because in essence the fuel cools the carburetor to some > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > conditions, depending on how long the vehicle sits between starts. The fuel > > can sometimes percolate until the bowl is empty. The percolation can cause > > the fuel to siphon itself out of the carb through the fuel passages and into > > the engine. > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > working properly. Try checking both volume and pressure. I'm not sure of the > > volume specs for your pump, but most of them are usually about a pint in > > 20-30 seconds of cranking. You'll have to check a service manual for your > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > air instead of fuel, this can also lead to the percolation condition. The > > volume tests should reveal a suction problem as well. > > > > You may want to check the fuel you've been using. Maybe your gas station got > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > vehicles just flat won't run right on that stuff. > > > > As far as the spark being weak, I would say possible but not likely. Most > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > means that even with 8 volts going to the coil, you would have over 12000 > > volts going to the plugs. While this is not optimum, it will definitely fire > > a plug enough to start the engine. Remember, a lot of the old point systems > > had a ballast resistor in the ignition circuit to intentionally cut the > > voltage back while cranking. > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
More than likely you are right Mike. I am just trying to give him other
possibilities to check on. I really believe it is a fuel issue one way or another. Chris "Mike Romain" <romainm@sympatico.ca> wrote in message news:3F84C160.BEFBACD6@sympatico.ca... > Just a couple comments. > > A vapor or percolation lock will shut down a carb. If there isn't fuel > pushing, the couple squirts you can get out of the accelerator pump > won't start the engine. They just give a dry spark plug with a slight > gas smell. > > And the ballast resistor is to give it 9 or so volts when running, the > solenoid to coil tag gives battery power in a start, which is down below > 12 usually with the starter sucking on it. > > It being still hot and dying is weird, but a shot of gas down the carb > will tell all. Likely a rubber hose between the tank and frame or frame > and engine has a crack, so sometimes it air locks fast, sometimes slow > depending on the angle it stopped at. > > Mike > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > 88 Cherokee 235 BFG AT's > > c wrote: > > > > <averyislandboy@yahoo.com> wrote in message > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > Mike Romain <romainm@sympatico.ca> wrote in message > > news:<3F83124C.E7063767@sympatico.ca>... > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > and see what happens. > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > a torn diaphragm on the pump. > > > > > > The pump is brand new last month. > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > nope smells like SAE 30 > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > it has had 12 volts. > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > open while trying to start it. > > > > > > > > > > > Mike > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > up. Which was totally out of the normal pattern because it was cold > > > and rainy. It also didn't start right up this morning, which is > > > atypical. It started a couple of times throughout the day, but when > > > it came to going home time it would not start. The engine was still > > > warm from having driven to the office from our pilot plant in the > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > couple of times for giggles and cranked. No start. Aha! I have the > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > it to my nose, but that's it. I don't think that that's classic > > > textbook flooded car "wet". So much for my theories to date. Not > > > having a remote starter (my wife wasn't at work with me, and the > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > I scratched my head for a while, cranked it once with the plug hanging > > > over the alternator (not that I could even begin to see it from the > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > to verify if it was flooded) and confused, I drive home brainstorming > > > new theories. > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > and it's good, but what if my starter and solenoid are getting "worn" > > > and sucking more juice than they should, that could drop the system > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > thinking about putting my spare battery in the passenger floor and > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > idea? Other suggestions? Like I've described, once the thing is > > > started it runs fine, but when it's running, the alternator is keeping > > > the coil at a happy 12-13V. > > > > OK, I might have a couple ideas here based on all the things I've read in > > this thread. First off, all of this is based on memory from what I've read, > > so bear with me if I repeat something you've tried. I remember you saying > > that when you pumped the accelerator after sitting, that the pump shot was > > good for a couple shots and then it "went dry". This seems wrong to me. You > > should get quite a few shots before the float bowl empties out. Definitely > > more than 2 or 3. This leads me to believe that either the float level is > > way too low, or possibly the fuel in the bowl is vaporizing from > > percolation, or both. A carb has more tendency to percolate when the float > > level is low because in essence the fuel cools the carburetor to some > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > conditions, depending on how long the vehicle sits between starts. The fuel > > can sometimes percolate until the bowl is empty. The percolation can cause > > the fuel to siphon itself out of the carb through the fuel passages and into > > the engine. > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > working properly. Try checking both volume and pressure. I'm not sure of the > > volume specs for your pump, but most of them are usually about a pint in > > 20-30 seconds of cranking. You'll have to check a service manual for your > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > air instead of fuel, this can also lead to the percolation condition. The > > volume tests should reveal a suction problem as well. > > > > You may want to check the fuel you've been using. Maybe your gas station got > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > vehicles just flat won't run right on that stuff. > > > > As far as the spark being weak, I would say possible but not likely. Most > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > means that even with 8 volts going to the coil, you would have over 12000 > > volts going to the plugs. While this is not optimum, it will definitely fire > > a plug enough to start the engine. Remember, a lot of the old point systems > > had a ballast resistor in the ignition circuit to intentionally cut the > > voltage back while cranking. > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
More than likely you are right Mike. I am just trying to give him other
possibilities to check on. I really believe it is a fuel issue one way or another. Chris "Mike Romain" <romainm@sympatico.ca> wrote in message news:3F84C160.BEFBACD6@sympatico.ca... > Just a couple comments. > > A vapor or percolation lock will shut down a carb. If there isn't fuel > pushing, the couple squirts you can get out of the accelerator pump > won't start the engine. They just give a dry spark plug with a slight > gas smell. > > And the ballast resistor is to give it 9 or so volts when running, the > solenoid to coil tag gives battery power in a start, which is down below > 12 usually with the starter sucking on it. > > It being still hot and dying is weird, but a shot of gas down the carb > will tell all. Likely a rubber hose between the tank and frame or frame > and engine has a crack, so sometimes it air locks fast, sometimes slow > depending on the angle it stopped at. > > Mike > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > 88 Cherokee 235 BFG AT's > > c wrote: > > > > <averyislandboy@yahoo.com> wrote in message > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > Mike Romain <romainm@sympatico.ca> wrote in message > > news:<3F83124C.E7063767@sympatico.ca>... > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > and see what happens. > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > a torn diaphragm on the pump. > > > > > > The pump is brand new last month. > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > nope smells like SAE 30 > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > it has had 12 volts. > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > open while trying to start it. > > > > > > > > > > > Mike > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > up. Which was totally out of the normal pattern because it was cold > > > and rainy. It also didn't start right up this morning, which is > > > atypical. It started a couple of times throughout the day, but when > > > it came to going home time it would not start. The engine was still > > > warm from having driven to the office from our pilot plant in the > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > couple of times for giggles and cranked. No start. Aha! I have the > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > it to my nose, but that's it. I don't think that that's classic > > > textbook flooded car "wet". So much for my theories to date. Not > > > having a remote starter (my wife wasn't at work with me, and the > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > I scratched my head for a while, cranked it once with the plug hanging > > > over the alternator (not that I could even begin to see it from the > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > to verify if it was flooded) and confused, I drive home brainstorming > > > new theories. > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > and it's good, but what if my starter and solenoid are getting "worn" > > > and sucking more juice than they should, that could drop the system > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > thinking about putting my spare battery in the passenger floor and > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > idea? Other suggestions? Like I've described, once the thing is > > > started it runs fine, but when it's running, the alternator is keeping > > > the coil at a happy 12-13V. > > > > OK, I might have a couple ideas here based on all the things I've read in > > this thread. First off, all of this is based on memory from what I've read, > > so bear with me if I repeat something you've tried. I remember you saying > > that when you pumped the accelerator after sitting, that the pump shot was > > good for a couple shots and then it "went dry". This seems wrong to me. You > > should get quite a few shots before the float bowl empties out. Definitely > > more than 2 or 3. This leads me to believe that either the float level is > > way too low, or possibly the fuel in the bowl is vaporizing from > > percolation, or both. A carb has more tendency to percolate when the float > > level is low because in essence the fuel cools the carburetor to some > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > conditions, depending on how long the vehicle sits between starts. The fuel > > can sometimes percolate until the bowl is empty. The percolation can cause > > the fuel to siphon itself out of the carb through the fuel passages and into > > the engine. > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > working properly. Try checking both volume and pressure. I'm not sure of the > > volume specs for your pump, but most of them are usually about a pint in > > 20-30 seconds of cranking. You'll have to check a service manual for your > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > air instead of fuel, this can also lead to the percolation condition. The > > volume tests should reveal a suction problem as well. > > > > You may want to check the fuel you've been using. Maybe your gas station got > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > vehicles just flat won't run right on that stuff. > > > > As far as the spark being weak, I would say possible but not likely. Most > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > means that even with 8 volts going to the coil, you would have over 12000 > > volts going to the plugs. While this is not optimum, it will definitely fire > > a plug enough to start the engine. Remember, a lot of the old point systems > > had a ballast resistor in the ignition circuit to intentionally cut the > > voltage back while cranking. > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>...
> Just a couple comments. > > A vapor or percolation lock will shut down a carb. If there isn't fuel > pushing, the couple squirts you can get out of the accelerator pump > won't start the engine. They just give a dry spark plug with a slight > gas smell. > > And the ballast resistor is to give it 9 or so volts when running, the > solenoid to coil tag gives battery power in a start, which is down below > 12 usually with the starter sucking on it. > > It being still hot and dying is weird, but a shot of gas down the carb > will tell all. Likely a rubber hose between the tank and frame or frame > and engine has a crack, so sometimes it air locks fast, sometimes slow > depending on the angle it stopped at. > Okay, shot down the carb did not work at all. Started small and worked up to enough to soak the plugs. Didn't even try to start, not even a little cough. I rechecked the pumper pumps till dry bowl. After sitting for 3-4 hours with the fuel bowl vent hose off (I was still checking to see if pressure building between the carbon canister and the carb was a problem) it took 4 squirts to run it dry. I turned it over for 3 seconds to fill the bowl and tried the pumper again. 17 squirts to dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the volume (~100 mL in 8 sec). That seemed pretty good to me. So I start from the beginning again. It's never taken me so long to get it started as yesterday. And Voila -- no spark at plug #1. Rechecked my ground and wire snugness -- no spark A-ha! This I can deal with. So I go through the ignition electronics troubleshooting flowchart in the dealer service manual. With the key on the positive terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. The next step is to disconnect the suppressor. Well that's long gone, so I skip that step. Next is to pull loose the "I" wire from the starter solenoid and check the coil positive terminal. My solenoid doesn't look anything like the book's solenoid so I pull each wire off in succession and check the voltage -- never goes to 6 V. Next is to jumper the negative terminal of the coil to ground and check the voltage -- AHA -- 6.0 volts. Check the continuity between the neg terminal and ECM connector pin #42 -- continuity good. Next step -- replace the ECM. Major bummer. That's $180 bucks, says friendly Advance Auto chick (I've got their number programmed into my cell phone). So, thanks for your advice and patience. You guys have been great. Anybody have any ideas on how to do an off-vehicle verification that my ECM is dead? I was going to just buy a new one and see if it fixed the problem and return it if it didn't. But before I shell out $180 I'd like to verify it somehow. Bob V. > Mike > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > 88 Cherokee 235 BFG AT's > > c wrote: > > > > <averyislandboy@yahoo.com> wrote in message > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F83124C.E7063767@sympatico.ca>... > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > and see what happens. > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > a torn diaphragm on the pump. > > > > > > The pump is brand new last month. > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > nope smells like SAE 30 > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > it has had 12 volts. > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > open while trying to start it. > > > > > > > > > > > Mike > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > up. Which was totally out of the normal pattern because it was cold > > > and rainy. It also didn't start right up this morning, which is > > > atypical. It started a couple of times throughout the day, but when > > > it came to going home time it would not start. The engine was still > > > warm from having driven to the office from our pilot plant in the > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > couple of times for giggles and cranked. No start. Aha! I have the > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > it to my nose, but that's it. I don't think that that's classic > > > textbook flooded car "wet". So much for my theories to date. Not > > > having a remote starter (my wife wasn't at work with me, and the > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > I scratched my head for a while, cranked it once with the plug hanging > > > over the alternator (not that I could even begin to see it from the > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > to verify if it was flooded) and confused, I drive home brainstorming > > > new theories. > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > and it's good, but what if my starter and solenoid are getting "worn" > > > and sucking more juice than they should, that could drop the system > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > thinking about putting my spare battery in the passenger floor and > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > idea? Other suggestions? Like I've described, once the thing is > > > started it runs fine, but when it's running, the alternator is keeping > > > the coil at a happy 12-13V. > > > > OK, I might have a couple ideas here based on all the things I've read in > > this thread. First off, all of this is based on memory from what I've read, > > so bear with me if I repeat something you've tried. I remember you saying > > that when you pumped the accelerator after sitting, that the pump shot was > > good for a couple shots and then it "went dry". This seems wrong to me. You > > should get quite a few shots before the float bowl empties out. Definitely > > more than 2 or 3. This leads me to believe that either the float level is > > way too low, or possibly the fuel in the bowl is vaporizing from > > percolation, or both. A carb has more tendency to percolate when the float > > level is low because in essence the fuel cools the carburetor to some > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > conditions, depending on how long the vehicle sits between starts. The fuel > > can sometimes percolate until the bowl is empty. The percolation can cause > > the fuel to siphon itself out of the carb through the fuel passages and into > > the engine. > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > working properly. Try checking both volume and pressure. I'm not sure of the > > volume specs for your pump, but most of them are usually about a pint in > > 20-30 seconds of cranking. You'll have to check a service manual for your > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > air instead of fuel, this can also lead to the percolation condition. The > > volume tests should reveal a suction problem as well. > > > > You may want to check the fuel you've been using. Maybe your gas station got > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > vehicles just flat won't run right on that stuff. > > > > As far as the spark being weak, I would say possible but not likely. Most > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > means that even with 8 volts going to the coil, you would have over 12000 > > volts going to the plugs. While this is not optimum, it will definitely fire > > a plug enough to start the engine. Remember, a lot of the old point systems > > had a ballast resistor in the ignition circuit to intentionally cut the > > voltage back while cranking. > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>...
> Just a couple comments. > > A vapor or percolation lock will shut down a carb. If there isn't fuel > pushing, the couple squirts you can get out of the accelerator pump > won't start the engine. They just give a dry spark plug with a slight > gas smell. > > And the ballast resistor is to give it 9 or so volts when running, the > solenoid to coil tag gives battery power in a start, which is down below > 12 usually with the starter sucking on it. > > It being still hot and dying is weird, but a shot of gas down the carb > will tell all. Likely a rubber hose between the tank and frame or frame > and engine has a crack, so sometimes it air locks fast, sometimes slow > depending on the angle it stopped at. > Okay, shot down the carb did not work at all. Started small and worked up to enough to soak the plugs. Didn't even try to start, not even a little cough. I rechecked the pumper pumps till dry bowl. After sitting for 3-4 hours with the fuel bowl vent hose off (I was still checking to see if pressure building between the carbon canister and the carb was a problem) it took 4 squirts to run it dry. I turned it over for 3 seconds to fill the bowl and tried the pumper again. 17 squirts to dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the volume (~100 mL in 8 sec). That seemed pretty good to me. So I start from the beginning again. It's never taken me so long to get it started as yesterday. And Voila -- no spark at plug #1. Rechecked my ground and wire snugness -- no spark A-ha! This I can deal with. So I go through the ignition electronics troubleshooting flowchart in the dealer service manual. With the key on the positive terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. The next step is to disconnect the suppressor. Well that's long gone, so I skip that step. Next is to pull loose the "I" wire from the starter solenoid and check the coil positive terminal. My solenoid doesn't look anything like the book's solenoid so I pull each wire off in succession and check the voltage -- never goes to 6 V. Next is to jumper the negative terminal of the coil to ground and check the voltage -- AHA -- 6.0 volts. Check the continuity between the neg terminal and ECM connector pin #42 -- continuity good. Next step -- replace the ECM. Major bummer. That's $180 bucks, says friendly Advance Auto chick (I've got their number programmed into my cell phone). So, thanks for your advice and patience. You guys have been great. Anybody have any ideas on how to do an off-vehicle verification that my ECM is dead? I was going to just buy a new one and see if it fixed the problem and return it if it didn't. But before I shell out $180 I'd like to verify it somehow. Bob V. > Mike > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > 88 Cherokee 235 BFG AT's > > c wrote: > > > > <averyislandboy@yahoo.com> wrote in message > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F83124C.E7063767@sympatico.ca>... > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > and see what happens. > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > a torn diaphragm on the pump. > > > > > > The pump is brand new last month. > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > nope smells like SAE 30 > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > it has had 12 volts. > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > open while trying to start it. > > > > > > > > > > > Mike > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > up. Which was totally out of the normal pattern because it was cold > > > and rainy. It also didn't start right up this morning, which is > > > atypical. It started a couple of times throughout the day, but when > > > it came to going home time it would not start. The engine was still > > > warm from having driven to the office from our pilot plant in the > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > couple of times for giggles and cranked. No start. Aha! I have the > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > it to my nose, but that's it. I don't think that that's classic > > > textbook flooded car "wet". So much for my theories to date. Not > > > having a remote starter (my wife wasn't at work with me, and the > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > I scratched my head for a while, cranked it once with the plug hanging > > > over the alternator (not that I could even begin to see it from the > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > to verify if it was flooded) and confused, I drive home brainstorming > > > new theories. > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > and it's good, but what if my starter and solenoid are getting "worn" > > > and sucking more juice than they should, that could drop the system > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > thinking about putting my spare battery in the passenger floor and > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > idea? Other suggestions? Like I've described, once the thing is > > > started it runs fine, but when it's running, the alternator is keeping > > > the coil at a happy 12-13V. > > > > OK, I might have a couple ideas here based on all the things I've read in > > this thread. First off, all of this is based on memory from what I've read, > > so bear with me if I repeat something you've tried. I remember you saying > > that when you pumped the accelerator after sitting, that the pump shot was > > good for a couple shots and then it "went dry". This seems wrong to me. You > > should get quite a few shots before the float bowl empties out. Definitely > > more than 2 or 3. This leads me to believe that either the float level is > > way too low, or possibly the fuel in the bowl is vaporizing from > > percolation, or both. A carb has more tendency to percolate when the float > > level is low because in essence the fuel cools the carburetor to some > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > conditions, depending on how long the vehicle sits between starts. The fuel > > can sometimes percolate until the bowl is empty. The percolation can cause > > the fuel to siphon itself out of the carb through the fuel passages and into > > the engine. > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > working properly. Try checking both volume and pressure. I'm not sure of the > > volume specs for your pump, but most of them are usually about a pint in > > 20-30 seconds of cranking. You'll have to check a service manual for your > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > air instead of fuel, this can also lead to the percolation condition. The > > volume tests should reveal a suction problem as well. > > > > You may want to check the fuel you've been using. Maybe your gas station got > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > vehicles just flat won't run right on that stuff. > > > > As far as the spark being weak, I would say possible but not likely. Most > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > means that even with 8 volts going to the coil, you would have over 12000 > > volts going to the plugs. While this is not optimum, it will definitely fire > > a plug enough to start the engine. Remember, a lot of the old point systems > > had a ballast resistor in the ignition circuit to intentionally cut the > > voltage back while cranking. > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>...
> Just a couple comments. > > A vapor or percolation lock will shut down a carb. If there isn't fuel > pushing, the couple squirts you can get out of the accelerator pump > won't start the engine. They just give a dry spark plug with a slight > gas smell. > > And the ballast resistor is to give it 9 or so volts when running, the > solenoid to coil tag gives battery power in a start, which is down below > 12 usually with the starter sucking on it. > > It being still hot and dying is weird, but a shot of gas down the carb > will tell all. Likely a rubber hose between the tank and frame or frame > and engine has a crack, so sometimes it air locks fast, sometimes slow > depending on the angle it stopped at. > Okay, shot down the carb did not work at all. Started small and worked up to enough to soak the plugs. Didn't even try to start, not even a little cough. I rechecked the pumper pumps till dry bowl. After sitting for 3-4 hours with the fuel bowl vent hose off (I was still checking to see if pressure building between the carbon canister and the carb was a problem) it took 4 squirts to run it dry. I turned it over for 3 seconds to fill the bowl and tried the pumper again. 17 squirts to dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the volume (~100 mL in 8 sec). That seemed pretty good to me. So I start from the beginning again. It's never taken me so long to get it started as yesterday. And Voila -- no spark at plug #1. Rechecked my ground and wire snugness -- no spark A-ha! This I can deal with. So I go through the ignition electronics troubleshooting flowchart in the dealer service manual. With the key on the positive terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. The next step is to disconnect the suppressor. Well that's long gone, so I skip that step. Next is to pull loose the "I" wire from the starter solenoid and check the coil positive terminal. My solenoid doesn't look anything like the book's solenoid so I pull each wire off in succession and check the voltage -- never goes to 6 V. Next is to jumper the negative terminal of the coil to ground and check the voltage -- AHA -- 6.0 volts. Check the continuity between the neg terminal and ECM connector pin #42 -- continuity good. Next step -- replace the ECM. Major bummer. That's $180 bucks, says friendly Advance Auto chick (I've got their number programmed into my cell phone). So, thanks for your advice and patience. You guys have been great. Anybody have any ideas on how to do an off-vehicle verification that my ECM is dead? I was going to just buy a new one and see if it fixed the problem and return it if it didn't. But before I shell out $180 I'd like to verify it somehow. Bob V. > Mike > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > 88 Cherokee 235 BFG AT's > > c wrote: > > > > <averyislandboy@yahoo.com> wrote in message > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F83124C.E7063767@sympatico.ca>... > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > and see what happens. > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > a torn diaphragm on the pump. > > > > > > The pump is brand new last month. > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > nope smells like SAE 30 > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > it has had 12 volts. > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > open while trying to start it. > > > > > > > > > > > Mike > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > up. Which was totally out of the normal pattern because it was cold > > > and rainy. It also didn't start right up this morning, which is > > > atypical. It started a couple of times throughout the day, but when > > > it came to going home time it would not start. The engine was still > > > warm from having driven to the office from our pilot plant in the > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > couple of times for giggles and cranked. No start. Aha! I have the > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > it to my nose, but that's it. I don't think that that's classic > > > textbook flooded car "wet". So much for my theories to date. Not > > > having a remote starter (my wife wasn't at work with me, and the > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > I scratched my head for a while, cranked it once with the plug hanging > > > over the alternator (not that I could even begin to see it from the > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > to verify if it was flooded) and confused, I drive home brainstorming > > > new theories. > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > and it's good, but what if my starter and solenoid are getting "worn" > > > and sucking more juice than they should, that could drop the system > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > thinking about putting my spare battery in the passenger floor and > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > idea? Other suggestions? Like I've described, once the thing is > > > started it runs fine, but when it's running, the alternator is keeping > > > the coil at a happy 12-13V. > > > > OK, I might have a couple ideas here based on all the things I've read in > > this thread. First off, all of this is based on memory from what I've read, > > so bear with me if I repeat something you've tried. I remember you saying > > that when you pumped the accelerator after sitting, that the pump shot was > > good for a couple shots and then it "went dry". This seems wrong to me. You > > should get quite a few shots before the float bowl empties out. Definitely > > more than 2 or 3. This leads me to believe that either the float level is > > way too low, or possibly the fuel in the bowl is vaporizing from > > percolation, or both. A carb has more tendency to percolate when the float > > level is low because in essence the fuel cools the carburetor to some > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > conditions, depending on how long the vehicle sits between starts. The fuel > > can sometimes percolate until the bowl is empty. The percolation can cause > > the fuel to siphon itself out of the carb through the fuel passages and into > > the engine. > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > working properly. Try checking both volume and pressure. I'm not sure of the > > volume specs for your pump, but most of them are usually about a pint in > > 20-30 seconds of cranking. You'll have to check a service manual for your > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > air instead of fuel, this can also lead to the percolation condition. The > > volume tests should reveal a suction problem as well. > > > > You may want to check the fuel you've been using. Maybe your gas station got > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > vehicles just flat won't run right on that stuff. > > > > As far as the spark being weak, I would say possible but not likely. Most > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > means that even with 8 volts going to the coil, you would have over 12000 > > volts going to the plugs. While this is not optimum, it will definitely fire > > a plug enough to start the engine. Remember, a lot of the old point systems > > had a ballast resistor in the ignition circuit to intentionally cut the > > voltage back while cranking. > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Interesting....
When you crank the starter can you see 9-12 volts at the coil positive? With the key in run, you see 9 volts at the coil positive right? 6 volts is on the low side, most come in around 9. If you don't see voltage at the coil positive with the starter turning you likely have a solenoid or relay on the firewall by the battery problem. $180.00 for an ECM????? Holy crap! They are only $70.00 or so up here in Canada..... There is no way to test them. I keep a spare on hand for that purpose. Mike "averyislandboy@yahoo.com" wrote: > > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>... > > Just a couple comments. > > > > A vapor or percolation lock will shut down a carb. If there isn't fuel > > pushing, the couple squirts you can get out of the accelerator pump > > won't start the engine. They just give a dry spark plug with a slight > > gas smell. > > > > And the ballast resistor is to give it 9 or so volts when running, the > > solenoid to coil tag gives battery power in a start, which is down below > > 12 usually with the starter sucking on it. > > > > It being still hot and dying is weird, but a shot of gas down the carb > > will tell all. Likely a rubber hose between the tank and frame or frame > > and engine has a crack, so sometimes it air locks fast, sometimes slow > > depending on the angle it stopped at. > > > > Okay, shot down the carb did not work at all. Started small and > worked up to enough to soak the plugs. Didn't even try to start, not > even a little cough. > > I rechecked the pumper pumps till dry bowl. After sitting for 3-4 > hours with the fuel bowl vent hose off (I was still checking to see if > pressure building between the carbon canister and the carb was a > problem) it took 4 squirts to run it dry. I turned it over for 3 > seconds to fill the bowl and tried the pumper again. 17 squirts to > dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the > volume (~100 mL in 8 sec). That seemed pretty good to me. > > So I start from the beginning again. It's never taken me so long to > get it started as yesterday. And Voila -- no spark at plug #1. > Rechecked my ground and wire snugness -- no spark A-ha! This I can > deal with. So I go through the ignition electronics troubleshooting > flowchart in the dealer service manual. With the key on the positive > terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. > The next step is to disconnect the suppressor. Well that's long gone, > so I skip that step. Next is to pull loose the "I" wire from the > starter solenoid and check the coil positive terminal. My solenoid > doesn't look anything like the book's solenoid so I pull each wire off > in succession and check the voltage -- never goes to 6 V. Next is to > jumper the negative terminal of the coil to ground and check the > voltage -- AHA -- 6.0 volts. Check the continuity between the neg > terminal and ECM connector pin #42 -- continuity good. Next step -- > replace the ECM. Major bummer. That's $180 bucks, says friendly > Advance Auto chick (I've got their number programmed into my cell > phone). > > So, thanks for your advice and patience. You guys have been great. > Anybody have any ideas on how to do an off-vehicle verification that > my ECM is dead? I was going to just buy a new one and see if it fixed > the problem and return it if it didn't. But before I shell out $180 > I'd like to verify it somehow. > > Bob V. > > > Mike > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > > 88 Cherokee 235 BFG AT's > > > > c wrote: > > > > > > <averyislandboy@yahoo.com> wrote in message > > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > > Mike Romain <romainm@sympatico.ca> wrote in message > > news:<3F83124C.E7063767@sympatico.ca>... > > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > > and see what happens. > > > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > > a torn diaphragm on the pump. > > > > > > > > The pump is brand new last month. > > > > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > > > nope smells like SAE 30 > > > > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > > it has had 12 volts. > > > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > > open while trying to start it. > > > > > > > > > > > > > > Mike > > > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > > up. Which was totally out of the normal pattern because it was cold > > > > and rainy. It also didn't start right up this morning, which is > > > > atypical. It started a couple of times throughout the day, but when > > > > it came to going home time it would not start. The engine was still > > > > warm from having driven to the office from our pilot plant in the > > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > > couple of times for giggles and cranked. No start. Aha! I have the > > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > > it to my nose, but that's it. I don't think that that's classic > > > > textbook flooded car "wet". So much for my theories to date. Not > > > > having a remote starter (my wife wasn't at work with me, and the > > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > > I scratched my head for a while, cranked it once with the plug hanging > > > > over the alternator (not that I could even begin to see it from the > > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > > to verify if it was flooded) and confused, I drive home brainstorming > > > > new theories. > > > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > > and it's good, but what if my starter and solenoid are getting "worn" > > > > and sucking more juice than they should, that could drop the system > > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > > thinking about putting my spare battery in the passenger floor and > > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > > idea? Other suggestions? Like I've described, once the thing is > > > > started it runs fine, but when it's running, the alternator is keeping > > > > the coil at a happy 12-13V. > > > > > > OK, I might have a couple ideas here based on all the things I've read in > > > this thread. First off, all of this is based on memory from what I've read, > > > so bear with me if I repeat something you've tried. I remember you saying > > > that when you pumped the accelerator after sitting, that the pump shot was > > > good for a couple shots and then it "went dry". This seems wrong to me. You > > > should get quite a few shots before the float bowl empties out. Definitely > > > more than 2 or 3. This leads me to believe that either the float level is > > > way too low, or possibly the fuel in the bowl is vaporizing from > > > percolation, or both. A carb has more tendency to percolate when the float > > > level is low because in essence the fuel cools the carburetor to some > > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > > conditions, depending on how long the vehicle sits between starts. The fuel > > > can sometimes percolate until the bowl is empty. The percolation can cause > > > the fuel to siphon itself out of the carb through the fuel passages and into > > > the engine. > > > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > > working properly. Try checking both volume and pressure. I'm not sure of the > > > volume specs for your pump, but most of them are usually about a pint in > > > 20-30 seconds of cranking. You'll have to check a service manual for your > > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > > air instead of fuel, this can also lead to the percolation condition. The > > > volume tests should reveal a suction problem as well. > > > > > > You may want to check the fuel you've been using. Maybe your gas station got > > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > > vehicles just flat won't run right on that stuff. > > > > > > As far as the spark being weak, I would say possible but not likely. Most > > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > > means that even with 8 volts going to the coil, you would have over 12000 > > > volts going to the plugs. While this is not optimum, it will definitely fire > > > a plug enough to start the engine. Remember, a lot of the old point systems > > > had a ballast resistor in the ignition circuit to intentionally cut the > > > voltage back while cranking. > > > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Interesting....
When you crank the starter can you see 9-12 volts at the coil positive? With the key in run, you see 9 volts at the coil positive right? 6 volts is on the low side, most come in around 9. If you don't see voltage at the coil positive with the starter turning you likely have a solenoid or relay on the firewall by the battery problem. $180.00 for an ECM????? Holy crap! They are only $70.00 or so up here in Canada..... There is no way to test them. I keep a spare on hand for that purpose. Mike "averyislandboy@yahoo.com" wrote: > > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>... > > Just a couple comments. > > > > A vapor or percolation lock will shut down a carb. If there isn't fuel > > pushing, the couple squirts you can get out of the accelerator pump > > won't start the engine. They just give a dry spark plug with a slight > > gas smell. > > > > And the ballast resistor is to give it 9 or so volts when running, the > > solenoid to coil tag gives battery power in a start, which is down below > > 12 usually with the starter sucking on it. > > > > It being still hot and dying is weird, but a shot of gas down the carb > > will tell all. Likely a rubber hose between the tank and frame or frame > > and engine has a crack, so sometimes it air locks fast, sometimes slow > > depending on the angle it stopped at. > > > > Okay, shot down the carb did not work at all. Started small and > worked up to enough to soak the plugs. Didn't even try to start, not > even a little cough. > > I rechecked the pumper pumps till dry bowl. After sitting for 3-4 > hours with the fuel bowl vent hose off (I was still checking to see if > pressure building between the carbon canister and the carb was a > problem) it took 4 squirts to run it dry. I turned it over for 3 > seconds to fill the bowl and tried the pumper again. 17 squirts to > dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the > volume (~100 mL in 8 sec). That seemed pretty good to me. > > So I start from the beginning again. It's never taken me so long to > get it started as yesterday. And Voila -- no spark at plug #1. > Rechecked my ground and wire snugness -- no spark A-ha! This I can > deal with. So I go through the ignition electronics troubleshooting > flowchart in the dealer service manual. With the key on the positive > terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. > The next step is to disconnect the suppressor. Well that's long gone, > so I skip that step. Next is to pull loose the "I" wire from the > starter solenoid and check the coil positive terminal. My solenoid > doesn't look anything like the book's solenoid so I pull each wire off > in succession and check the voltage -- never goes to 6 V. Next is to > jumper the negative terminal of the coil to ground and check the > voltage -- AHA -- 6.0 volts. Check the continuity between the neg > terminal and ECM connector pin #42 -- continuity good. Next step -- > replace the ECM. Major bummer. That's $180 bucks, says friendly > Advance Auto chick (I've got their number programmed into my cell > phone). > > So, thanks for your advice and patience. You guys have been great. > Anybody have any ideas on how to do an off-vehicle verification that > my ECM is dead? I was going to just buy a new one and see if it fixed > the problem and return it if it didn't. But before I shell out $180 > I'd like to verify it somehow. > > Bob V. > > > Mike > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > > 88 Cherokee 235 BFG AT's > > > > c wrote: > > > > > > <averyislandboy@yahoo.com> wrote in message > > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > > Mike Romain <romainm@sympatico.ca> wrote in message > > news:<3F83124C.E7063767@sympatico.ca>... > > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > > and see what happens. > > > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > > a torn diaphragm on the pump. > > > > > > > > The pump is brand new last month. > > > > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > > > nope smells like SAE 30 > > > > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > > it has had 12 volts. > > > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > > open while trying to start it. > > > > > > > > > > > > > > Mike > > > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > > up. Which was totally out of the normal pattern because it was cold > > > > and rainy. It also didn't start right up this morning, which is > > > > atypical. It started a couple of times throughout the day, but when > > > > it came to going home time it would not start. The engine was still > > > > warm from having driven to the office from our pilot plant in the > > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > > couple of times for giggles and cranked. No start. Aha! I have the > > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > > it to my nose, but that's it. I don't think that that's classic > > > > textbook flooded car "wet". So much for my theories to date. Not > > > > having a remote starter (my wife wasn't at work with me, and the > > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > > I scratched my head for a while, cranked it once with the plug hanging > > > > over the alternator (not that I could even begin to see it from the > > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > > to verify if it was flooded) and confused, I drive home brainstorming > > > > new theories. > > > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > > and it's good, but what if my starter and solenoid are getting "worn" > > > > and sucking more juice than they should, that could drop the system > > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > > thinking about putting my spare battery in the passenger floor and > > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > > idea? Other suggestions? Like I've described, once the thing is > > > > started it runs fine, but when it's running, the alternator is keeping > > > > the coil at a happy 12-13V. > > > > > > OK, I might have a couple ideas here based on all the things I've read in > > > this thread. First off, all of this is based on memory from what I've read, > > > so bear with me if I repeat something you've tried. I remember you saying > > > that when you pumped the accelerator after sitting, that the pump shot was > > > good for a couple shots and then it "went dry". This seems wrong to me. You > > > should get quite a few shots before the float bowl empties out. Definitely > > > more than 2 or 3. This leads me to believe that either the float level is > > > way too low, or possibly the fuel in the bowl is vaporizing from > > > percolation, or both. A carb has more tendency to percolate when the float > > > level is low because in essence the fuel cools the carburetor to some > > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > > conditions, depending on how long the vehicle sits between starts. The fuel > > > can sometimes percolate until the bowl is empty. The percolation can cause > > > the fuel to siphon itself out of the carb through the fuel passages and into > > > the engine. > > > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > > working properly. Try checking both volume and pressure. I'm not sure of the > > > volume specs for your pump, but most of them are usually about a pint in > > > 20-30 seconds of cranking. You'll have to check a service manual for your > > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > > air instead of fuel, this can also lead to the percolation condition. The > > > volume tests should reveal a suction problem as well. > > > > > > You may want to check the fuel you've been using. Maybe your gas station got > > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > > vehicles just flat won't run right on that stuff. > > > > > > As far as the spark being weak, I would say possible but not likely. Most > > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > > means that even with 8 volts going to the coil, you would have over 12000 > > > volts going to the plugs. While this is not optimum, it will definitely fire > > > a plug enough to start the engine. Remember, a lot of the old point systems > > > had a ballast resistor in the ignition circuit to intentionally cut the > > > voltage back while cranking. > > > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Interesting....
When you crank the starter can you see 9-12 volts at the coil positive? With the key in run, you see 9 volts at the coil positive right? 6 volts is on the low side, most come in around 9. If you don't see voltage at the coil positive with the starter turning you likely have a solenoid or relay on the firewall by the battery problem. $180.00 for an ECM????? Holy crap! They are only $70.00 or so up here in Canada..... There is no way to test them. I keep a spare on hand for that purpose. Mike "averyislandboy@yahoo.com" wrote: > > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>... > > Just a couple comments. > > > > A vapor or percolation lock will shut down a carb. If there isn't fuel > > pushing, the couple squirts you can get out of the accelerator pump > > won't start the engine. They just give a dry spark plug with a slight > > gas smell. > > > > And the ballast resistor is to give it 9 or so volts when running, the > > solenoid to coil tag gives battery power in a start, which is down below > > 12 usually with the starter sucking on it. > > > > It being still hot and dying is weird, but a shot of gas down the carb > > will tell all. Likely a rubber hose between the tank and frame or frame > > and engine has a crack, so sometimes it air locks fast, sometimes slow > > depending on the angle it stopped at. > > > > Okay, shot down the carb did not work at all. Started small and > worked up to enough to soak the plugs. Didn't even try to start, not > even a little cough. > > I rechecked the pumper pumps till dry bowl. After sitting for 3-4 > hours with the fuel bowl vent hose off (I was still checking to see if > pressure building between the carbon canister and the carb was a > problem) it took 4 squirts to run it dry. I turned it over for 3 > seconds to fill the bowl and tried the pumper again. 17 squirts to > dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the > volume (~100 mL in 8 sec). That seemed pretty good to me. > > So I start from the beginning again. It's never taken me so long to > get it started as yesterday. And Voila -- no spark at plug #1. > Rechecked my ground and wire snugness -- no spark A-ha! This I can > deal with. So I go through the ignition electronics troubleshooting > flowchart in the dealer service manual. With the key on the positive > terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. > The next step is to disconnect the suppressor. Well that's long gone, > so I skip that step. Next is to pull loose the "I" wire from the > starter solenoid and check the coil positive terminal. My solenoid > doesn't look anything like the book's solenoid so I pull each wire off > in succession and check the voltage -- never goes to 6 V. Next is to > jumper the negative terminal of the coil to ground and check the > voltage -- AHA -- 6.0 volts. Check the continuity between the neg > terminal and ECM connector pin #42 -- continuity good. Next step -- > replace the ECM. Major bummer. That's $180 bucks, says friendly > Advance Auto chick (I've got their number programmed into my cell > phone). > > So, thanks for your advice and patience. You guys have been great. > Anybody have any ideas on how to do an off-vehicle verification that > my ECM is dead? I was going to just buy a new one and see if it fixed > the problem and return it if it didn't. But before I shell out $180 > I'd like to verify it somehow. > > Bob V. > > > Mike > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > > 88 Cherokee 235 BFG AT's > > > > c wrote: > > > > > > <averyislandboy@yahoo.com> wrote in message > > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > > Mike Romain <romainm@sympatico.ca> wrote in message > > news:<3F83124C.E7063767@sympatico.ca>... > > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > > and see what happens. > > > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > > a torn diaphragm on the pump. > > > > > > > > The pump is brand new last month. > > > > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > > > nope smells like SAE 30 > > > > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > > it has had 12 volts. > > > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > > open while trying to start it. > > > > > > > > > > > > > > Mike > > > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > > up. Which was totally out of the normal pattern because it was cold > > > > and rainy. It also didn't start right up this morning, which is > > > > atypical. It started a couple of times throughout the day, but when > > > > it came to going home time it would not start. The engine was still > > > > warm from having driven to the office from our pilot plant in the > > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > > couple of times for giggles and cranked. No start. Aha! I have the > > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > > it to my nose, but that's it. I don't think that that's classic > > > > textbook flooded car "wet". So much for my theories to date. Not > > > > having a remote starter (my wife wasn't at work with me, and the > > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > > I scratched my head for a while, cranked it once with the plug hanging > > > > over the alternator (not that I could even begin to see it from the > > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > > to verify if it was flooded) and confused, I drive home brainstorming > > > > new theories. > > > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > > and it's good, but what if my starter and solenoid are getting "worn" > > > > and sucking more juice than they should, that could drop the system > > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > > thinking about putting my spare battery in the passenger floor and > > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > > idea? Other suggestions? Like I've described, once the thing is > > > > started it runs fine, but when it's running, the alternator is keeping > > > > the coil at a happy 12-13V. > > > > > > OK, I might have a couple ideas here based on all the things I've read in > > > this thread. First off, all of this is based on memory from what I've read, > > > so bear with me if I repeat something you've tried. I remember you saying > > > that when you pumped the accelerator after sitting, that the pump shot was > > > good for a couple shots and then it "went dry". This seems wrong to me. You > > > should get quite a few shots before the float bowl empties out. Definitely > > > more than 2 or 3. This leads me to believe that either the float level is > > > way too low, or possibly the fuel in the bowl is vaporizing from > > > percolation, or both. A carb has more tendency to percolate when the float > > > level is low because in essence the fuel cools the carburetor to some > > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > > conditions, depending on how long the vehicle sits between starts. The fuel > > > can sometimes percolate until the bowl is empty. The percolation can cause > > > the fuel to siphon itself out of the carb through the fuel passages and into > > > the engine. > > > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > > working properly. Try checking both volume and pressure. I'm not sure of the > > > volume specs for your pump, but most of them are usually about a pint in > > > 20-30 seconds of cranking. You'll have to check a service manual for your > > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > > air instead of fuel, this can also lead to the percolation condition. The > > > volume tests should reveal a suction problem as well. > > > > > > You may want to check the fuel you've been using. Maybe your gas station got > > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > > vehicles just flat won't run right on that stuff. > > > > > > As far as the spark being weak, I would say possible but not likely. Most > > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > > means that even with 8 volts going to the coil, you would have over 12000 > > > volts going to the plugs. While this is not optimum, it will definitely fire > > > a plug enough to start the engine. Remember, a lot of the old point systems > > > had a ballast resistor in the ignition circuit to intentionally cut the > > > voltage back while cranking. > > > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
averyislandboy@yahoo.com wrote:
> Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F84C160.BEFBACD6@sympatico.ca>... >> Just a couple comments. >> >> A vapor or percolation lock will shut down a carb. If there isn't >> fuel pushing, the couple squirts you can get out of the accelerator >> pump won't start the engine. They just give a dry spark plug with a >> slight gas smell. >> >> And the ballast resistor is to give it 9 or so volts when running, >> the solenoid to coil tag gives battery power in a start, which is >> down below 12 usually with the starter sucking on it. >> >> It being still hot and dying is weird, but a shot of gas down the >> carb will tell all. Likely a rubber hose between the tank and frame >> or frame and engine has a crack, so sometimes it air locks fast, >> sometimes slow depending on the angle it stopped at. >> > > Okay, shot down the carb did not work at all. Started small and > worked up to enough to soak the plugs. Didn't even try to start, not > even a little cough. > > I rechecked the pumper pumps till dry bowl. After sitting for 3-4 > hours with the fuel bowl vent hose off (I was still checking to see if > pressure building between the carbon canister and the carb was a > problem) it took 4 squirts to run it dry. I turned it over for 3 > seconds to fill the bowl and tried the pumper again. 17 squirts to > dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the > volume (~100 mL in 8 sec). That seemed pretty good to me. > > So I start from the beginning again. It's never taken me so long to > get it started as yesterday. And Voila -- no spark at plug #1. > Rechecked my ground and wire snugness -- no spark A-ha! This I can > deal with. So I go through the ignition electronics troubleshooting > flowchart in the dealer service manual. With the key on the positive > terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. > The next step is to disconnect the suppressor. Well that's long gone, > so I skip that step. Next is to pull loose the "I" wire from the > starter solenoid and check the coil positive terminal. My solenoid > doesn't look anything like the book's solenoid so I pull each wire off > in succession and check the voltage -- never goes to 6 V. Next is to > jumper the negative terminal of the coil to ground and check the > voltage -- AHA -- 6.0 volts. Check the continuity between the neg > terminal and ECM connector pin #42 -- continuity good. Next step -- > replace the ECM. Major bummer. That's $180 bucks, says friendly > Advance Auto chick (I've got their number programmed into my cell > phone). > > So, thanks for your advice and patience. You guys have been great. > Anybody have any ideas on how to do an off-vehicle verification that > my ECM is dead? I was going to just buy a new one and see if it fixed > the problem and return it if it didn't. But before I shell out $180 > I'd like to verify it somehow. > > Bob V. > > Be careful with the plan of returning an ECM. Most part stores won't take returns on electrical gismos. However, most ECMs can be tested with either a special tester, or a multimeter. Not sure on yours, but Mike probably knows. Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
averyislandboy@yahoo.com wrote:
> Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F84C160.BEFBACD6@sympatico.ca>... >> Just a couple comments. >> >> A vapor or percolation lock will shut down a carb. If there isn't >> fuel pushing, the couple squirts you can get out of the accelerator >> pump won't start the engine. They just give a dry spark plug with a >> slight gas smell. >> >> And the ballast resistor is to give it 9 or so volts when running, >> the solenoid to coil tag gives battery power in a start, which is >> down below 12 usually with the starter sucking on it. >> >> It being still hot and dying is weird, but a shot of gas down the >> carb will tell all. Likely a rubber hose between the tank and frame >> or frame and engine has a crack, so sometimes it air locks fast, >> sometimes slow depending on the angle it stopped at. >> > > Okay, shot down the carb did not work at all. Started small and > worked up to enough to soak the plugs. Didn't even try to start, not > even a little cough. > > I rechecked the pumper pumps till dry bowl. After sitting for 3-4 > hours with the fuel bowl vent hose off (I was still checking to see if > pressure building between the carbon canister and the carb was a > problem) it took 4 squirts to run it dry. I turned it over for 3 > seconds to fill the bowl and tried the pumper again. 17 squirts to > dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the > volume (~100 mL in 8 sec). That seemed pretty good to me. > > So I start from the beginning again. It's never taken me so long to > get it started as yesterday. And Voila -- no spark at plug #1. > Rechecked my ground and wire snugness -- no spark A-ha! This I can > deal with. So I go through the ignition electronics troubleshooting > flowchart in the dealer service manual. With the key on the positive > terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. > The next step is to disconnect the suppressor. Well that's long gone, > so I skip that step. Next is to pull loose the "I" wire from the > starter solenoid and check the coil positive terminal. My solenoid > doesn't look anything like the book's solenoid so I pull each wire off > in succession and check the voltage -- never goes to 6 V. Next is to > jumper the negative terminal of the coil to ground and check the > voltage -- AHA -- 6.0 volts. Check the continuity between the neg > terminal and ECM connector pin #42 -- continuity good. Next step -- > replace the ECM. Major bummer. That's $180 bucks, says friendly > Advance Auto chick (I've got their number programmed into my cell > phone). > > So, thanks for your advice and patience. You guys have been great. > Anybody have any ideas on how to do an off-vehicle verification that > my ECM is dead? I was going to just buy a new one and see if it fixed > the problem and return it if it didn't. But before I shell out $180 > I'd like to verify it somehow. > > Bob V. > > Be careful with the plan of returning an ECM. Most part stores won't take returns on electrical gismos. However, most ECMs can be tested with either a special tester, or a multimeter. Not sure on yours, but Mike probably knows. Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
averyislandboy@yahoo.com wrote:
> Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F84C160.BEFBACD6@sympatico.ca>... >> Just a couple comments. >> >> A vapor or percolation lock will shut down a carb. If there isn't >> fuel pushing, the couple squirts you can get out of the accelerator >> pump won't start the engine. They just give a dry spark plug with a >> slight gas smell. >> >> And the ballast resistor is to give it 9 or so volts when running, >> the solenoid to coil tag gives battery power in a start, which is >> down below 12 usually with the starter sucking on it. >> >> It being still hot and dying is weird, but a shot of gas down the >> carb will tell all. Likely a rubber hose between the tank and frame >> or frame and engine has a crack, so sometimes it air locks fast, >> sometimes slow depending on the angle it stopped at. >> > > Okay, shot down the carb did not work at all. Started small and > worked up to enough to soak the plugs. Didn't even try to start, not > even a little cough. > > I rechecked the pumper pumps till dry bowl. After sitting for 3-4 > hours with the fuel bowl vent hose off (I was still checking to see if > pressure building between the carbon canister and the carb was a > problem) it took 4 squirts to run it dry. I turned it over for 3 > seconds to fill the bowl and tried the pumper again. 17 squirts to > dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the > volume (~100 mL in 8 sec). That seemed pretty good to me. > > So I start from the beginning again. It's never taken me so long to > get it started as yesterday. And Voila -- no spark at plug #1. > Rechecked my ground and wire snugness -- no spark A-ha! This I can > deal with. So I go through the ignition electronics troubleshooting > flowchart in the dealer service manual. With the key on the positive > terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. > The next step is to disconnect the suppressor. Well that's long gone, > so I skip that step. Next is to pull loose the "I" wire from the > starter solenoid and check the coil positive terminal. My solenoid > doesn't look anything like the book's solenoid so I pull each wire off > in succession and check the voltage -- never goes to 6 V. Next is to > jumper the negative terminal of the coil to ground and check the > voltage -- AHA -- 6.0 volts. Check the continuity between the neg > terminal and ECM connector pin #42 -- continuity good. Next step -- > replace the ECM. Major bummer. That's $180 bucks, says friendly > Advance Auto chick (I've got their number programmed into my cell > phone). > > So, thanks for your advice and patience. You guys have been great. > Anybody have any ideas on how to do an off-vehicle verification that > my ECM is dead? I was going to just buy a new one and see if it fixed > the problem and return it if it didn't. But before I shell out $180 > I'd like to verify it somehow. > > Bob V. > > Be careful with the plan of returning an ECM. Most part stores won't take returns on electrical gismos. However, most ECMs can be tested with either a special tester, or a multimeter. Not sure on yours, but Mike probably knows. Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
<averyislandboy@yahoo.com> wrote in message news:a188e6f3.0310101115.573f91e9@posting.google.c om... .... > The next step is to disconnect the suppressor. Well that's long gone, > so I skip that step. You must like blowing up modules... that supressor is not there just for good looks. __ Steve .. |
Re: '88 YJ 258 ci with carter Hard Warm Start
<averyislandboy@yahoo.com> wrote in message news:a188e6f3.0310101115.573f91e9@posting.google.c om... .... > The next step is to disconnect the suppressor. Well that's long gone, > so I skip that step. You must like blowing up modules... that supressor is not there just for good looks. __ Steve .. |
Re: '88 YJ 258 ci with carter Hard Warm Start
<averyislandboy@yahoo.com> wrote in message news:a188e6f3.0310101115.573f91e9@posting.google.c om... .... > The next step is to disconnect the suppressor. Well that's long gone, > so I skip that step. You must like blowing up modules... that supressor is not there just for good looks. __ Steve .. |
Re: '88 YJ 258 ci with carter Hard Warm Start
In message <a188e6f3.0310101115.573f91e9@posting.google.com >,
"averyislandboy@yahoo.com" wrote: >Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>... >> Just a couple comments. >> >> A vapor or percolation lock will shut down a carb. If there isn't fuel >> pushing, the couple squirts you can get out of the accelerator pump >> won't start the engine. They just give a dry spark plug with a slight >> gas smell. >> >> And the ballast resistor is to give it 9 or so volts when running, the >> solenoid to coil tag gives battery power in a start, which is down below >> 12 usually with the starter sucking on it. >> >> It being still hot and dying is weird, but a shot of gas down the carb >> will tell all. Likely a rubber hose between the tank and frame or frame >> and engine has a crack, so sometimes it air locks fast, sometimes slow >> depending on the angle it stopped at. >> > >Okay, shot down the carb did not work at all. Started small and >worked up to enough to soak the plugs. Didn't even try to start, not >even a little cough. > >I rechecked the pumper pumps till dry bowl. After sitting for 3-4 >hours with the fuel bowl vent hose off (I was still checking to see if >pressure building between the carbon canister and the carb was a >problem) it took 4 squirts to run it dry. I turned it over for 3 >seconds to fill the bowl and tried the pumper again. 17 squirts to >dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the >volume (~100 mL in 8 sec). That seemed pretty good to me. > >So I start from the beginning again. It's never taken me so long to >get it started as yesterday. And Voila -- no spark at plug #1. >Rechecked my ground and wire snugness -- no spark A-ha! This I can >deal with. So I go through the ignition electronics troubleshooting >flowchart in the dealer service manual. With the key on the positive >terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. >The next step is to disconnect the suppressor. Well that's long gone, >so I skip that step. Next is to pull loose the "I" wire from the >starter solenoid and check the coil positive terminal. My solenoid >doesn't look anything like the book's solenoid so I pull each wire off >in succession and check the voltage -- never goes to 6 V. Next is to >jumper the negative terminal of the coil to ground and check the >voltage -- AHA -- 6.0 volts. Check the continuity between the neg >terminal and ECM connector pin #42 -- continuity good. Next step -- >replace the ECM. Major bummer. That's $180 bucks, says friendly >Advance Auto chick (I've got their number programmed into my cell >phone). "ECM" and "pin 42" make me think you're talking about the engine computer. You may be confused. The neg terminal of the coil doesn't connect to the ECM. It connects to the ignition module. The ignition module is probably bad. Very common. A few things to check... I don't remember the color of the wires, but the ign module needs 12v with the key on, and on another wire, 12v while cranking. I believe it's the wires in the 2-wire connector at the module. Also, the whole ignition system grounds through the distributor. There's 2 screws in the distributor that hold the pickup assy down. One has a rubber grommet with an eyelet on it. That's the ground. Make sure it's tight. I've also seen cracked distributor housings that can cause an intermittent loss of ground. The good news is ignition modules don't cost $180. > >So, thanks for your advice and patience. You guys have been great. >Anybody have any ideas on how to do an off-vehicle verification that >my ECM is dead? I was going to just buy a new one and see if it fixed >the problem and return it if it didn't. But before I shell out $180 >I'd like to verify it somehow. > >Bob V. > > > >> Mike >> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 >> 88 Cherokee 235 BFG AT's >> >> c wrote: >> > >> > <averyislandboy@yahoo.com> wrote in message >> > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... >> > > Mike Romain <romainm@sympatico.ca> wrote in message >> news:<3F83124C.E7063767@sympatico.ca>... >> > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb >> > > > and see what happens. >> > > > >> > > > If it fires up, you have a hole in the gas line on the suction side of >> > > > the pump or a dead pump that is letting the gas backflow to the tank or >> > > > a torn diaphragm on the pump. >> > > >> > > The pump is brand new last month. >> > > >> > > > >> > > > Does the oil on the dipstick smell like gas? >> > > >> > > nope smells like SAE 30 >> > > >> > > > >> > > > Oh, the choke is an electric timer job. >> > > > >> > > > It will be totally closed after 5 minutes and opens according to how >> > > > long 12 volts has been going to it. Piece of crap actually because it >> > > > doesn't have a clue how hot or cold the engine really is, just how long >> > > > it has had 12 volts. >> > > >> > > I don't think the choke is the prime offender since I tend to wedge it >> > > open while trying to start it. >> > > >> > > > >> > > > Mike >> > > >> > > Well, I actually took the plug wrench with me on a day that it acted >> > > up. Which was totally out of the normal pattern because it was cold >> > > and rainy. It also didn't start right up this morning, which is >> > > atypical. It started a couple of times throughout the day, but when >> > > it came to going home time it would not start. The engine was still >> > > warm from having driven to the office from our pilot plant in the >> > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a >> > > couple of times for giggles and cranked. No start. Aha! I have the >> > > plug wrench, pulled out old number 1 and Voila, the plug, much to my >> > > surprise was not wet. I could catch a faint whiff of petro when I put >> > > it to my nose, but that's it. I don't think that that's classic >> > > textbook flooded car "wet". So much for my theories to date. Not >> > > having a remote starter (my wife wasn't at work with me, and the >> > > cleaning lady had already gone home) I couldn't check if I had spark. >> > > I scratched my head for a while, cranked it once with the plug hanging >> > > over the alternator (not that I could even begin to see it from the >> > > driver's seat. I didn't have a screwdriver to jump my solenoid, just >> > > a 1/2" wrench and my socket driver which seemed like a bad idea on a >> > > rainy day). So I put the plug back in, crank it and doggone it if it >> > > doesn't start. Huh? Thankful (especially to Mike for encouraging me >> > > to verify if it was flooded) and confused, I drive home brainstorming >> > > new theories. >> > > >> > > What about if I had "weak spark"? I have checked the coil resistances >> > > and it's good, but what if my starter and solenoid are getting "worn" >> > > and sucking more juice than they should, that could drop the system >> > > voltage pretty low and without 11-12V, would the coil work right? I'm >> > > thinking about putting my spare battery in the passenger floor and >> > > wiring it directly into the coil to ensure it is seeing 12V. Whacked >> > > idea? Other suggestions? Like I've described, once the thing is >> > > started it runs fine, but when it's running, the alternator is keeping >> > > the coil at a happy 12-13V. >> > >> > OK, I might have a couple ideas here based on all the things I've read in >> > this thread. First off, all of this is based on memory from what I've read, >> > so bear with me if I repeat something you've tried. I remember you saying >> > that when you pumped the accelerator after sitting, that the pump shot was >> > good for a couple shots and then it "went dry". This seems wrong to me. You >> > should get quite a few shots before the float bowl empties out. Definitely >> > more than 2 or 3. This leads me to believe that either the float level is >> > way too low, or possibly the fuel in the bowl is vaporizing from >> > percolation, or both. A carb has more tendency to percolate when the float >> > level is low because in essence the fuel cools the carburetor to some >> > extent. Fuel percolation can also cause both flooded conditions and no fuel >> > conditions, depending on how long the vehicle sits between starts. The fuel >> > can sometimes percolate until the bowl is empty. The percolation can cause >> > the fuel to siphon itself out of the carb through the fuel passages and into >> > the engine. >> > >> > Also, regarding the fuel pump, just because it is new doesn't mean it is >> > working properly. Try checking both volume and pressure. I'm not sure of the >> > volume specs for your pump, but most of them are usually about a pint in >> > 20-30 seconds of cranking. You'll have to check a service manual for your >> > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike >> > said, also check all of your fuel lines for pinholes. If the pump is sucking >> > air instead of fuel, this can also lead to the percolation condition. The >> > volume tests should reveal a suction problem as well. >> > >> > You may want to check the fuel you've been using. Maybe your gas station got >> > some bad gas, or possibly they have mixed in that reconstituted crap. Some >> > vehicles just flat won't run right on that stuff. >> > >> > As far as the spark being weak, I would say possible but not likely. Most >> > factory coils "amplify" the voltage by a factor of about 1600 or more, which >> > means that even with 8 volts going to the coil, you would have over 12000 >> > volts going to the plugs. While this is not optimum, it will definitely fire >> > a plug enough to start the engine. Remember, a lot of the old point systems >> > had a ballast resistor in the ignition circuit to intentionally cut the >> > voltage back while cranking. >> > >> > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
In message <a188e6f3.0310101115.573f91e9@posting.google.com >,
"averyislandboy@yahoo.com" wrote: >Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>... >> Just a couple comments. >> >> A vapor or percolation lock will shut down a carb. If there isn't fuel >> pushing, the couple squirts you can get out of the accelerator pump >> won't start the engine. They just give a dry spark plug with a slight >> gas smell. >> >> And the ballast resistor is to give it 9 or so volts when running, the >> solenoid to coil tag gives battery power in a start, which is down below >> 12 usually with the starter sucking on it. >> >> It being still hot and dying is weird, but a shot of gas down the carb >> will tell all. Likely a rubber hose between the tank and frame or frame >> and engine has a crack, so sometimes it air locks fast, sometimes slow >> depending on the angle it stopped at. >> > >Okay, shot down the carb did not work at all. Started small and >worked up to enough to soak the plugs. Didn't even try to start, not >even a little cough. > >I rechecked the pumper pumps till dry bowl. After sitting for 3-4 >hours with the fuel bowl vent hose off (I was still checking to see if >pressure building between the carbon canister and the carb was a >problem) it took 4 squirts to run it dry. I turned it over for 3 >seconds to fill the bowl and tried the pumper again. 17 squirts to >dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the >volume (~100 mL in 8 sec). That seemed pretty good to me. > >So I start from the beginning again. It's never taken me so long to >get it started as yesterday. And Voila -- no spark at plug #1. >Rechecked my ground and wire snugness -- no spark A-ha! This I can >deal with. So I go through the ignition electronics troubleshooting >flowchart in the dealer service manual. With the key on the positive >terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. >The next step is to disconnect the suppressor. Well that's long gone, >so I skip that step. Next is to pull loose the "I" wire from the >starter solenoid and check the coil positive terminal. My solenoid >doesn't look anything like the book's solenoid so I pull each wire off >in succession and check the voltage -- never goes to 6 V. Next is to >jumper the negative terminal of the coil to ground and check the >voltage -- AHA -- 6.0 volts. Check the continuity between the neg >terminal and ECM connector pin #42 -- continuity good. Next step -- >replace the ECM. Major bummer. That's $180 bucks, says friendly >Advance Auto chick (I've got their number programmed into my cell >phone). "ECM" and "pin 42" make me think you're talking about the engine computer. You may be confused. The neg terminal of the coil doesn't connect to the ECM. It connects to the ignition module. The ignition module is probably bad. Very common. A few things to check... I don't remember the color of the wires, but the ign module needs 12v with the key on, and on another wire, 12v while cranking. I believe it's the wires in the 2-wire connector at the module. Also, the whole ignition system grounds through the distributor. There's 2 screws in the distributor that hold the pickup assy down. One has a rubber grommet with an eyelet on it. That's the ground. Make sure it's tight. I've also seen cracked distributor housings that can cause an intermittent loss of ground. The good news is ignition modules don't cost $180. > >So, thanks for your advice and patience. You guys have been great. >Anybody have any ideas on how to do an off-vehicle verification that >my ECM is dead? I was going to just buy a new one and see if it fixed >the problem and return it if it didn't. But before I shell out $180 >I'd like to verify it somehow. > >Bob V. > > > >> Mike >> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 >> 88 Cherokee 235 BFG AT's >> >> c wrote: >> > >> > <averyislandboy@yahoo.com> wrote in message >> > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... >> > > Mike Romain <romainm@sympatico.ca> wrote in message >> news:<3F83124C.E7063767@sympatico.ca>... >> > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb >> > > > and see what happens. >> > > > >> > > > If it fires up, you have a hole in the gas line on the suction side of >> > > > the pump or a dead pump that is letting the gas backflow to the tank or >> > > > a torn diaphragm on the pump. >> > > >> > > The pump is brand new last month. >> > > >> > > > >> > > > Does the oil on the dipstick smell like gas? >> > > >> > > nope smells like SAE 30 >> > > >> > > > >> > > > Oh, the choke is an electric timer job. >> > > > >> > > > It will be totally closed after 5 minutes and opens according to how >> > > > long 12 volts has been going to it. Piece of crap actually because it >> > > > doesn't have a clue how hot or cold the engine really is, just how long >> > > > it has had 12 volts. >> > > >> > > I don't think the choke is the prime offender since I tend to wedge it >> > > open while trying to start it. >> > > >> > > > >> > > > Mike >> > > >> > > Well, I actually took the plug wrench with me on a day that it acted >> > > up. Which was totally out of the normal pattern because it was cold >> > > and rainy. It also didn't start right up this morning, which is >> > > atypical. It started a couple of times throughout the day, but when >> > > it came to going home time it would not start. The engine was still >> > > warm from having driven to the office from our pilot plant in the >> > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a >> > > couple of times for giggles and cranked. No start. Aha! I have the >> > > plug wrench, pulled out old number 1 and Voila, the plug, much to my >> > > surprise was not wet. I could catch a faint whiff of petro when I put >> > > it to my nose, but that's it. I don't think that that's classic >> > > textbook flooded car "wet". So much for my theories to date. Not >> > > having a remote starter (my wife wasn't at work with me, and the >> > > cleaning lady had already gone home) I couldn't check if I had spark. >> > > I scratched my head for a while, cranked it once with the plug hanging >> > > over the alternator (not that I could even begin to see it from the >> > > driver's seat. I didn't have a screwdriver to jump my solenoid, just >> > > a 1/2" wrench and my socket driver which seemed like a bad idea on a >> > > rainy day). So I put the plug back in, crank it and doggone it if it >> > > doesn't start. Huh? Thankful (especially to Mike for encouraging me >> > > to verify if it was flooded) and confused, I drive home brainstorming >> > > new theories. >> > > >> > > What about if I had "weak spark"? I have checked the coil resistances >> > > and it's good, but what if my starter and solenoid are getting "worn" >> > > and sucking more juice than they should, that could drop the system >> > > voltage pretty low and without 11-12V, would the coil work right? I'm >> > > thinking about putting my spare battery in the passenger floor and >> > > wiring it directly into the coil to ensure it is seeing 12V. Whacked >> > > idea? Other suggestions? Like I've described, once the thing is >> > > started it runs fine, but when it's running, the alternator is keeping >> > > the coil at a happy 12-13V. >> > >> > OK, I might have a couple ideas here based on all the things I've read in >> > this thread. First off, all of this is based on memory from what I've read, >> > so bear with me if I repeat something you've tried. I remember you saying >> > that when you pumped the accelerator after sitting, that the pump shot was >> > good for a couple shots and then it "went dry". This seems wrong to me. You >> > should get quite a few shots before the float bowl empties out. Definitely >> > more than 2 or 3. This leads me to believe that either the float level is >> > way too low, or possibly the fuel in the bowl is vaporizing from >> > percolation, or both. A carb has more tendency to percolate when the float >> > level is low because in essence the fuel cools the carburetor to some >> > extent. Fuel percolation can also cause both flooded conditions and no fuel >> > conditions, depending on how long the vehicle sits between starts. The fuel >> > can sometimes percolate until the bowl is empty. The percolation can cause >> > the fuel to siphon itself out of the carb through the fuel passages and into >> > the engine. >> > >> > Also, regarding the fuel pump, just because it is new doesn't mean it is >> > working properly. Try checking both volume and pressure. I'm not sure of the >> > volume specs for your pump, but most of them are usually about a pint in >> > 20-30 seconds of cranking. You'll have to check a service manual for your >> > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike >> > said, also check all of your fuel lines for pinholes. If the pump is sucking >> > air instead of fuel, this can also lead to the percolation condition. The >> > volume tests should reveal a suction problem as well. >> > >> > You may want to check the fuel you've been using. Maybe your gas station got >> > some bad gas, or possibly they have mixed in that reconstituted crap. Some >> > vehicles just flat won't run right on that stuff. >> > >> > As far as the spark being weak, I would say possible but not likely. Most >> > factory coils "amplify" the voltage by a factor of about 1600 or more, which >> > means that even with 8 volts going to the coil, you would have over 12000 >> > volts going to the plugs. While this is not optimum, it will definitely fire >> > a plug enough to start the engine. Remember, a lot of the old point systems >> > had a ballast resistor in the ignition circuit to intentionally cut the >> > voltage back while cranking. >> > >> > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
In message <a188e6f3.0310101115.573f91e9@posting.google.com >,
"averyislandboy@yahoo.com" wrote: >Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>... >> Just a couple comments. >> >> A vapor or percolation lock will shut down a carb. If there isn't fuel >> pushing, the couple squirts you can get out of the accelerator pump >> won't start the engine. They just give a dry spark plug with a slight >> gas smell. >> >> And the ballast resistor is to give it 9 or so volts when running, the >> solenoid to coil tag gives battery power in a start, which is down below >> 12 usually with the starter sucking on it. >> >> It being still hot and dying is weird, but a shot of gas down the carb >> will tell all. Likely a rubber hose between the tank and frame or frame >> and engine has a crack, so sometimes it air locks fast, sometimes slow >> depending on the angle it stopped at. >> > >Okay, shot down the carb did not work at all. Started small and >worked up to enough to soak the plugs. Didn't even try to start, not >even a little cough. > >I rechecked the pumper pumps till dry bowl. After sitting for 3-4 >hours with the fuel bowl vent hose off (I was still checking to see if >pressure building between the carbon canister and the carb was a >problem) it took 4 squirts to run it dry. I turned it over for 3 >seconds to fill the bowl and tried the pumper again. 17 squirts to >dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the >volume (~100 mL in 8 sec). That seemed pretty good to me. > >So I start from the beginning again. It's never taken me so long to >get it started as yesterday. And Voila -- no spark at plug #1. >Rechecked my ground and wire snugness -- no spark A-ha! This I can >deal with. So I go through the ignition electronics troubleshooting >flowchart in the dealer service manual. With the key on the positive >terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. >The next step is to disconnect the suppressor. Well that's long gone, >so I skip that step. Next is to pull loose the "I" wire from the >starter solenoid and check the coil positive terminal. My solenoid >doesn't look anything like the book's solenoid so I pull each wire off >in succession and check the voltage -- never goes to 6 V. Next is to >jumper the negative terminal of the coil to ground and check the >voltage -- AHA -- 6.0 volts. Check the continuity between the neg >terminal and ECM connector pin #42 -- continuity good. Next step -- >replace the ECM. Major bummer. That's $180 bucks, says friendly >Advance Auto chick (I've got their number programmed into my cell >phone). "ECM" and "pin 42" make me think you're talking about the engine computer. You may be confused. The neg terminal of the coil doesn't connect to the ECM. It connects to the ignition module. The ignition module is probably bad. Very common. A few things to check... I don't remember the color of the wires, but the ign module needs 12v with the key on, and on another wire, 12v while cranking. I believe it's the wires in the 2-wire connector at the module. Also, the whole ignition system grounds through the distributor. There's 2 screws in the distributor that hold the pickup assy down. One has a rubber grommet with an eyelet on it. That's the ground. Make sure it's tight. I've also seen cracked distributor housings that can cause an intermittent loss of ground. The good news is ignition modules don't cost $180. > >So, thanks for your advice and patience. You guys have been great. >Anybody have any ideas on how to do an off-vehicle verification that >my ECM is dead? I was going to just buy a new one and see if it fixed >the problem and return it if it didn't. But before I shell out $180 >I'd like to verify it somehow. > >Bob V. > > > >> Mike >> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 >> 88 Cherokee 235 BFG AT's >> >> c wrote: >> > >> > <averyislandboy@yahoo.com> wrote in message >> > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... >> > > Mike Romain <romainm@sympatico.ca> wrote in message >> news:<3F83124C.E7063767@sympatico.ca>... >> > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb >> > > > and see what happens. >> > > > >> > > > If it fires up, you have a hole in the gas line on the suction side of >> > > > the pump or a dead pump that is letting the gas backflow to the tank or >> > > > a torn diaphragm on the pump. >> > > >> > > The pump is brand new last month. >> > > >> > > > >> > > > Does the oil on the dipstick smell like gas? >> > > >> > > nope smells like SAE 30 >> > > >> > > > >> > > > Oh, the choke is an electric timer job. >> > > > >> > > > It will be totally closed after 5 minutes and opens according to how >> > > > long 12 volts has been going to it. Piece of crap actually because it >> > > > doesn't have a clue how hot or cold the engine really is, just how long >> > > > it has had 12 volts. >> > > >> > > I don't think the choke is the prime offender since I tend to wedge it >> > > open while trying to start it. >> > > >> > > > >> > > > Mike >> > > >> > > Well, I actually took the plug wrench with me on a day that it acted >> > > up. Which was totally out of the normal pattern because it was cold >> > > and rainy. It also didn't start right up this morning, which is >> > > atypical. It started a couple of times throughout the day, but when >> > > it came to going home time it would not start. The engine was still >> > > warm from having driven to the office from our pilot plant in the >> > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a >> > > couple of times for giggles and cranked. No start. Aha! I have the >> > > plug wrench, pulled out old number 1 and Voila, the plug, much to my >> > > surprise was not wet. I could catch a faint whiff of petro when I put >> > > it to my nose, but that's it. I don't think that that's classic >> > > textbook flooded car "wet". So much for my theories to date. Not >> > > having a remote starter (my wife wasn't at work with me, and the >> > > cleaning lady had already gone home) I couldn't check if I had spark. >> > > I scratched my head for a while, cranked it once with the plug hanging >> > > over the alternator (not that I could even begin to see it from the >> > > driver's seat. I didn't have a screwdriver to jump my solenoid, just >> > > a 1/2" wrench and my socket driver which seemed like a bad idea on a >> > > rainy day). So I put the plug back in, crank it and doggone it if it >> > > doesn't start. Huh? Thankful (especially to Mike for encouraging me >> > > to verify if it was flooded) and confused, I drive home brainstorming >> > > new theories. >> > > >> > > What about if I had "weak spark"? I have checked the coil resistances >> > > and it's good, but what if my starter and solenoid are getting "worn" >> > > and sucking more juice than they should, that could drop the system >> > > voltage pretty low and without 11-12V, would the coil work right? I'm >> > > thinking about putting my spare battery in the passenger floor and >> > > wiring it directly into the coil to ensure it is seeing 12V. Whacked >> > > idea? Other suggestions? Like I've described, once the thing is >> > > started it runs fine, but when it's running, the alternator is keeping >> > > the coil at a happy 12-13V. >> > >> > OK, I might have a couple ideas here based on all the things I've read in >> > this thread. First off, all of this is based on memory from what I've read, >> > so bear with me if I repeat something you've tried. I remember you saying >> > that when you pumped the accelerator after sitting, that the pump shot was >> > good for a couple shots and then it "went dry". This seems wrong to me. You >> > should get quite a few shots before the float bowl empties out. Definitely >> > more than 2 or 3. This leads me to believe that either the float level is >> > way too low, or possibly the fuel in the bowl is vaporizing from >> > percolation, or both. A carb has more tendency to percolate when the float >> > level is low because in essence the fuel cools the carburetor to some >> > extent. Fuel percolation can also cause both flooded conditions and no fuel >> > conditions, depending on how long the vehicle sits between starts. The fuel >> > can sometimes percolate until the bowl is empty. The percolation can cause >> > the fuel to siphon itself out of the carb through the fuel passages and into >> > the engine. >> > >> > Also, regarding the fuel pump, just because it is new doesn't mean it is >> > working properly. Try checking both volume and pressure. I'm not sure of the >> > volume specs for your pump, but most of them are usually about a pint in >> > 20-30 seconds of cranking. You'll have to check a service manual for your >> > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike >> > said, also check all of your fuel lines for pinholes. If the pump is sucking >> > air instead of fuel, this can also lead to the percolation condition. The >> > volume tests should reveal a suction problem as well. >> > >> > You may want to check the fuel you've been using. Maybe your gas station got >> > some bad gas, or possibly they have mixed in that reconstituted crap. Some >> > vehicles just flat won't run right on that stuff. >> > >> > As far as the spark being weak, I would say possible but not likely. Most >> > factory coils "amplify" the voltage by a factor of about 1600 or more, which >> > means that even with 8 volts going to the coil, you would have over 12000 >> > volts going to the plugs. While this is not optimum, it will definitely fire >> > a plug enough to start the engine. Remember, a lot of the old point systems >> > had a ballast resistor in the ignition circuit to intentionally cut the >> > voltage back while cranking. >> > >> > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Mike Romain <romainm@sympatico.ca> wrote in message news:<3F8721E3.943964F2@sympatico.ca>...
> Interesting.... > > When you crank the starter can you see 9-12 volts at the coil positive? I see 12 volts with the key on. According to the Jeep Service Manual, I should only see 6 at the coil positive. After trying a bunch of stuff in their troubleshooting flow chart, you eventually jumper a ground to the neg terminal and the voltage drops to 6. They say that's a sure sign the ECM is dead. Another test is to turn the key on and check the current between pin D1 and ground of the 4-prong connector (2-prong still hooked up). They say it should be 1 amp, mine read 0. This also means dead ECM. I ran through every other ignition diagnosic except checking the resistance between two pins of the MCU (I didn't want to pull the dash and radio). Nothing else showed problematic that I could find. > > With the key in run, you see 9 volts at the coil positive right? 6 > volts is on the low side, most come in around 9. > > If you don't see voltage at the coil positive with the starter turning > you likely have a solenoid or relay on the firewall by the battery > problem. With the starter turning, it jumps to 12. > > $180.00 for an ECM????? > > Holy crap! They are only $70.00 or so up here in Canada..... The whackball new chick at the Advance Auto must have been impaired by the multiple eyebrow piercings. I went to the website today and found that they carry two versions (one with a lifetime warranty for $57 and an AC Delco with no warranty for $52). The $180 version is a hotrod package from Accel. So I have a new one being PDQ'd for tomorrow. Keep your fingers crossed. > > There is no way to test them. I keep a spare on hand for that purpose. > But you know after I get the new one in and if it fixes the Jeep I'm cutting that rascal open to see what the heck is in there. Right? It's prolly just a couple of relays and resistors and a fuse. Maybe not, but I'm going in. > Mike > Thanks Mike, I'll let you know how it goes tomorrow. Bob > "averyislandboy@yahoo.com" wrote: > > > > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>... > > > Just a couple comments. > > > > > > A vapor or percolation lock will shut down a carb. If there isn't fuel > > > pushing, the couple squirts you can get out of the accelerator pump > > > won't start the engine. They just give a dry spark plug with a slight > > > gas smell. > > > > > > And the ballast resistor is to give it 9 or so volts when running, the > > > solenoid to coil tag gives battery power in a start, which is down below > > > 12 usually with the starter sucking on it. > > > > > > It being still hot and dying is weird, but a shot of gas down the carb > > > will tell all. Likely a rubber hose between the tank and frame or frame > > > and engine has a crack, so sometimes it air locks fast, sometimes slow > > > depending on the angle it stopped at. > > > > > > > Okay, shot down the carb did not work at all. Started small and > > worked up to enough to soak the plugs. Didn't even try to start, not > > even a little cough. > > > > I rechecked the pumper pumps till dry bowl. After sitting for 3-4 > > hours with the fuel bowl vent hose off (I was still checking to see if > > pressure building between the carbon canister and the carb was a > > problem) it took 4 squirts to run it dry. I turned it over for 3 > > seconds to fill the bowl and tried the pumper again. 17 squirts to > > dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the > > volume (~100 mL in 8 sec). That seemed pretty good to me. > > > > So I start from the beginning again. It's never taken me so long to > > get it started as yesterday. And Voila -- no spark at plug #1. > > Rechecked my ground and wire snugness -- no spark A-ha! This I can > > deal with. So I go through the ignition electronics troubleshooting > > flowchart in the dealer service manual. With the key on the positive > > terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. > > The next step is to disconnect the suppressor. Well that's long gone, > > so I skip that step. Next is to pull loose the "I" wire from the > > starter solenoid and check the coil positive terminal. My solenoid > > doesn't look anything like the book's solenoid so I pull each wire off > > in succession and check the voltage -- never goes to 6 V. Next is to > > jumper the negative terminal of the coil to ground and check the > > voltage -- AHA -- 6.0 volts. Check the continuity between the neg > > terminal and ECM connector pin #42 -- continuity good. Next step -- > > replace the ECM. Major bummer. That's $180 bucks, says friendly > > Advance Auto chick (I've got their number programmed into my cell > > phone). > > > > So, thanks for your advice and patience. You guys have been great. > > Anybody have any ideas on how to do an off-vehicle verification that > > my ECM is dead? I was going to just buy a new one and see if it fixed > > the problem and return it if it didn't. But before I shell out $180 > > I'd like to verify it somehow. > > > > Bob V. > > > > > Mike > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > > > 88 Cherokee 235 BFG AT's > > > > > > c wrote: > > > > > > > > <averyislandboy@yahoo.com> wrote in message > > > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > > > Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F83124C.E7063767@sympatico.ca>... > > > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > > > and see what happens. > > > > > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > > > a torn diaphragm on the pump. > > > > > > > > > > The pump is brand new last month. > > > > > > > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > > > > > nope smells like SAE 30 > > > > > > > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > > > it has had 12 volts. > > > > > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > > > open while trying to start it. > > > > > > > > > > > > > > > > > Mike > > > > > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > > > up. Which was totally out of the normal pattern because it was cold > > > > > and rainy. It also didn't start right up this morning, which is > > > > > atypical. It started a couple of times throughout the day, but when > > > > > it came to going home time it would not start. The engine was still > > > > > warm from having driven to the office from our pilot plant in the > > > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > > > couple of times for giggles and cranked. No start. Aha! I have the > > > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > > > it to my nose, but that's it. I don't think that that's classic > > > > > textbook flooded car "wet". So much for my theories to date. Not > > > > > having a remote starter (my wife wasn't at work with me, and the > > > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > > > I scratched my head for a while, cranked it once with the plug hanging > > > > > over the alternator (not that I could even begin to see it from the > > > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > > > to verify if it was flooded) and confused, I drive home brainstorming > > > > > new theories. > > > > > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > > > and it's good, but what if my starter and solenoid are getting "worn" > > > > > and sucking more juice than they should, that could drop the system > > > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > > > thinking about putting my spare battery in the passenger floor and > > > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > > > idea? Other suggestions? Like I've described, once the thing is > > > > > started it runs fine, but when it's running, the alternator is keeping > > > > > the coil at a happy 12-13V. > > > > > > > > OK, I might have a couple ideas here based on all the things I've read in > > > > this thread. First off, all of this is based on memory from what I've read, > > > > so bear with me if I repeat something you've tried. I remember you saying > > > > that when you pumped the accelerator after sitting, that the pump shot was > > > > good for a couple shots and then it "went dry". This seems wrong to me. You > > > > should get quite a few shots before the float bowl empties out. Definitely > > > > more than 2 or 3. This leads me to believe that either the float level is > > > > way too low, or possibly the fuel in the bowl is vaporizing from > > > > percolation, or both. A carb has more tendency to percolate when the float > > > > level is low because in essence the fuel cools the carburetor to some > > > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > > > conditions, depending on how long the vehicle sits between starts. The fuel > > > > can sometimes percolate until the bowl is empty. The percolation can cause > > > > the fuel to siphon itself out of the carb through the fuel passages and into > > > > the engine. > > > > > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > > > working properly. Try checking both volume and pressure. I'm not sure of the > > > > volume specs for your pump, but most of them are usually about a pint in > > > > 20-30 seconds of cranking. You'll have to check a service manual for your > > > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > > > air instead of fuel, this can also lead to the percolation condition. The > > > > volume tests should reveal a suction problem as well. > > > > > > > > You may want to check the fuel you've been using. Maybe your gas station got > > > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > > > vehicles just flat won't run right on that stuff. > > > > > > > > As far as the spark being weak, I would say possible but not likely. Most > > > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > > > means that even with 8 volts going to the coil, you would have over 12000 > > > > volts going to the plugs. While this is not optimum, it will definitely fire > > > > a plug enough to start the engine. Remember, a lot of the old point systems > > > > had a ballast resistor in the ignition circuit to intentionally cut the > > > > voltage back while cranking. > > > > > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Mike Romain <romainm@sympatico.ca> wrote in message news:<3F8721E3.943964F2@sympatico.ca>...
> Interesting.... > > When you crank the starter can you see 9-12 volts at the coil positive? I see 12 volts with the key on. According to the Jeep Service Manual, I should only see 6 at the coil positive. After trying a bunch of stuff in their troubleshooting flow chart, you eventually jumper a ground to the neg terminal and the voltage drops to 6. They say that's a sure sign the ECM is dead. Another test is to turn the key on and check the current between pin D1 and ground of the 4-prong connector (2-prong still hooked up). They say it should be 1 amp, mine read 0. This also means dead ECM. I ran through every other ignition diagnosic except checking the resistance between two pins of the MCU (I didn't want to pull the dash and radio). Nothing else showed problematic that I could find. > > With the key in run, you see 9 volts at the coil positive right? 6 > volts is on the low side, most come in around 9. > > If you don't see voltage at the coil positive with the starter turning > you likely have a solenoid or relay on the firewall by the battery > problem. With the starter turning, it jumps to 12. > > $180.00 for an ECM????? > > Holy crap! They are only $70.00 or so up here in Canada..... The whackball new chick at the Advance Auto must have been impaired by the multiple eyebrow piercings. I went to the website today and found that they carry two versions (one with a lifetime warranty for $57 and an AC Delco with no warranty for $52). The $180 version is a hotrod package from Accel. So I have a new one being PDQ'd for tomorrow. Keep your fingers crossed. > > There is no way to test them. I keep a spare on hand for that purpose. > But you know after I get the new one in and if it fixes the Jeep I'm cutting that rascal open to see what the heck is in there. Right? It's prolly just a couple of relays and resistors and a fuse. Maybe not, but I'm going in. > Mike > Thanks Mike, I'll let you know how it goes tomorrow. Bob > "averyislandboy@yahoo.com" wrote: > > > > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>... > > > Just a couple comments. > > > > > > A vapor or percolation lock will shut down a carb. If there isn't fuel > > > pushing, the couple squirts you can get out of the accelerator pump > > > won't start the engine. They just give a dry spark plug with a slight > > > gas smell. > > > > > > And the ballast resistor is to give it 9 or so volts when running, the > > > solenoid to coil tag gives battery power in a start, which is down below > > > 12 usually with the starter sucking on it. > > > > > > It being still hot and dying is weird, but a shot of gas down the carb > > > will tell all. Likely a rubber hose between the tank and frame or frame > > > and engine has a crack, so sometimes it air locks fast, sometimes slow > > > depending on the angle it stopped at. > > > > > > > Okay, shot down the carb did not work at all. Started small and > > worked up to enough to soak the plugs. Didn't even try to start, not > > even a little cough. > > > > I rechecked the pumper pumps till dry bowl. After sitting for 3-4 > > hours with the fuel bowl vent hose off (I was still checking to see if > > pressure building between the carbon canister and the carb was a > > problem) it took 4 squirts to run it dry. I turned it over for 3 > > seconds to fill the bowl and tried the pumper again. 17 squirts to > > dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the > > volume (~100 mL in 8 sec). That seemed pretty good to me. > > > > So I start from the beginning again. It's never taken me so long to > > get it started as yesterday. And Voila -- no spark at plug #1. > > Rechecked my ground and wire snugness -- no spark A-ha! This I can > > deal with. So I go through the ignition electronics troubleshooting > > flowchart in the dealer service manual. With the key on the positive > > terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. > > The next step is to disconnect the suppressor. Well that's long gone, > > so I skip that step. Next is to pull loose the "I" wire from the > > starter solenoid and check the coil positive terminal. My solenoid > > doesn't look anything like the book's solenoid so I pull each wire off > > in succession and check the voltage -- never goes to 6 V. Next is to > > jumper the negative terminal of the coil to ground and check the > > voltage -- AHA -- 6.0 volts. Check the continuity between the neg > > terminal and ECM connector pin #42 -- continuity good. Next step -- > > replace the ECM. Major bummer. That's $180 bucks, says friendly > > Advance Auto chick (I've got their number programmed into my cell > > phone). > > > > So, thanks for your advice and patience. You guys have been great. > > Anybody have any ideas on how to do an off-vehicle verification that > > my ECM is dead? I was going to just buy a new one and see if it fixed > > the problem and return it if it didn't. But before I shell out $180 > > I'd like to verify it somehow. > > > > Bob V. > > > > > Mike > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > > > 88 Cherokee 235 BFG AT's > > > > > > c wrote: > > > > > > > > <averyislandboy@yahoo.com> wrote in message > > > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > > > Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F83124C.E7063767@sympatico.ca>... > > > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > > > and see what happens. > > > > > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > > > a torn diaphragm on the pump. > > > > > > > > > > The pump is brand new last month. > > > > > > > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > > > > > nope smells like SAE 30 > > > > > > > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > > > it has had 12 volts. > > > > > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > > > open while trying to start it. > > > > > > > > > > > > > > > > > Mike > > > > > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > > > up. Which was totally out of the normal pattern because it was cold > > > > > and rainy. It also didn't start right up this morning, which is > > > > > atypical. It started a couple of times throughout the day, but when > > > > > it came to going home time it would not start. The engine was still > > > > > warm from having driven to the office from our pilot plant in the > > > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > > > couple of times for giggles and cranked. No start. Aha! I have the > > > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > > > it to my nose, but that's it. I don't think that that's classic > > > > > textbook flooded car "wet". So much for my theories to date. Not > > > > > having a remote starter (my wife wasn't at work with me, and the > > > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > > > I scratched my head for a while, cranked it once with the plug hanging > > > > > over the alternator (not that I could even begin to see it from the > > > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > > > to verify if it was flooded) and confused, I drive home brainstorming > > > > > new theories. > > > > > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > > > and it's good, but what if my starter and solenoid are getting "worn" > > > > > and sucking more juice than they should, that could drop the system > > > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > > > thinking about putting my spare battery in the passenger floor and > > > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > > > idea? Other suggestions? Like I've described, once the thing is > > > > > started it runs fine, but when it's running, the alternator is keeping > > > > > the coil at a happy 12-13V. > > > > > > > > OK, I might have a couple ideas here based on all the things I've read in > > > > this thread. First off, all of this is based on memory from what I've read, > > > > so bear with me if I repeat something you've tried. I remember you saying > > > > that when you pumped the accelerator after sitting, that the pump shot was > > > > good for a couple shots and then it "went dry". This seems wrong to me. You > > > > should get quite a few shots before the float bowl empties out. Definitely > > > > more than 2 or 3. This leads me to believe that either the float level is > > > > way too low, or possibly the fuel in the bowl is vaporizing from > > > > percolation, or both. A carb has more tendency to percolate when the float > > > > level is low because in essence the fuel cools the carburetor to some > > > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > > > conditions, depending on how long the vehicle sits between starts. The fuel > > > > can sometimes percolate until the bowl is empty. The percolation can cause > > > > the fuel to siphon itself out of the carb through the fuel passages and into > > > > the engine. > > > > > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > > > working properly. Try checking both volume and pressure. I'm not sure of the > > > > volume specs for your pump, but most of them are usually about a pint in > > > > 20-30 seconds of cranking. You'll have to check a service manual for your > > > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > > > air instead of fuel, this can also lead to the percolation condition. The > > > > volume tests should reveal a suction problem as well. > > > > > > > > You may want to check the fuel you've been using. Maybe your gas station got > > > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > > > vehicles just flat won't run right on that stuff. > > > > > > > > As far as the spark being weak, I would say possible but not likely. Most > > > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > > > means that even with 8 volts going to the coil, you would have over 12000 > > > > volts going to the plugs. While this is not optimum, it will definitely fire > > > > a plug enough to start the engine. Remember, a lot of the old point systems > > > > had a ballast resistor in the ignition circuit to intentionally cut the > > > > voltage back while cranking. > > > > > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
Mike Romain <romainm@sympatico.ca> wrote in message news:<3F8721E3.943964F2@sympatico.ca>...
> Interesting.... > > When you crank the starter can you see 9-12 volts at the coil positive? I see 12 volts with the key on. According to the Jeep Service Manual, I should only see 6 at the coil positive. After trying a bunch of stuff in their troubleshooting flow chart, you eventually jumper a ground to the neg terminal and the voltage drops to 6. They say that's a sure sign the ECM is dead. Another test is to turn the key on and check the current between pin D1 and ground of the 4-prong connector (2-prong still hooked up). They say it should be 1 amp, mine read 0. This also means dead ECM. I ran through every other ignition diagnosic except checking the resistance between two pins of the MCU (I didn't want to pull the dash and radio). Nothing else showed problematic that I could find. > > With the key in run, you see 9 volts at the coil positive right? 6 > volts is on the low side, most come in around 9. > > If you don't see voltage at the coil positive with the starter turning > you likely have a solenoid or relay on the firewall by the battery > problem. With the starter turning, it jumps to 12. > > $180.00 for an ECM????? > > Holy crap! They are only $70.00 or so up here in Canada..... The whackball new chick at the Advance Auto must have been impaired by the multiple eyebrow piercings. I went to the website today and found that they carry two versions (one with a lifetime warranty for $57 and an AC Delco with no warranty for $52). The $180 version is a hotrod package from Accel. So I have a new one being PDQ'd for tomorrow. Keep your fingers crossed. > > There is no way to test them. I keep a spare on hand for that purpose. > But you know after I get the new one in and if it fixes the Jeep I'm cutting that rascal open to see what the heck is in there. Right? It's prolly just a couple of relays and resistors and a fuse. Maybe not, but I'm going in. > Mike > Thanks Mike, I'll let you know how it goes tomorrow. Bob > "averyislandboy@yahoo.com" wrote: > > > > Mike Romain <romainm@sympatico.ca> wrote in message news:<3F84C160.BEFBACD6@sympatico.ca>... > > > Just a couple comments. > > > > > > A vapor or percolation lock will shut down a carb. If there isn't fuel > > > pushing, the couple squirts you can get out of the accelerator pump > > > won't start the engine. They just give a dry spark plug with a slight > > > gas smell. > > > > > > And the ballast resistor is to give it 9 or so volts when running, the > > > solenoid to coil tag gives battery power in a start, which is down below > > > 12 usually with the starter sucking on it. > > > > > > It being still hot and dying is weird, but a shot of gas down the carb > > > will tell all. Likely a rubber hose between the tank and frame or frame > > > and engine has a crack, so sometimes it air locks fast, sometimes slow > > > depending on the angle it stopped at. > > > > > > > Okay, shot down the carb did not work at all. Started small and > > worked up to enough to soak the plugs. Didn't even try to start, not > > even a little cough. > > > > I rechecked the pumper pumps till dry bowl. After sitting for 3-4 > > hours with the fuel bowl vent hose off (I was still checking to see if > > pressure building between the carbon canister and the carb was a > > problem) it took 4 squirts to run it dry. I turned it over for 3 > > seconds to fill the bowl and tried the pumper again. 17 squirts to > > dry bowl. Again, 17 squirts. I verified the pressure (6 psi) and the > > volume (~100 mL in 8 sec). That seemed pretty good to me. > > > > So I start from the beginning again. It's never taken me so long to > > get it started as yesterday. And Voila -- no spark at plug #1. > > Rechecked my ground and wire snugness -- no spark A-ha! This I can > > deal with. So I go through the ignition electronics troubleshooting > > flowchart in the dealer service manual. With the key on the positive > > terminal at the coil should be 6V +/- 0.5V. Well it's reading 9 V. > > The next step is to disconnect the suppressor. Well that's long gone, > > so I skip that step. Next is to pull loose the "I" wire from the > > starter solenoid and check the coil positive terminal. My solenoid > > doesn't look anything like the book's solenoid so I pull each wire off > > in succession and check the voltage -- never goes to 6 V. Next is to > > jumper the negative terminal of the coil to ground and check the > > voltage -- AHA -- 6.0 volts. Check the continuity between the neg > > terminal and ECM connector pin #42 -- continuity good. Next step -- > > replace the ECM. Major bummer. That's $180 bucks, says friendly > > Advance Auto chick (I've got their number programmed into my cell > > phone). > > > > So, thanks for your advice and patience. You guys have been great. > > Anybody have any ideas on how to do an off-vehicle verification that > > my ECM is dead? I was going to just buy a new one and see if it fixed > > the problem and return it if it didn't. But before I shell out $180 > > I'd like to verify it somehow. > > > > Bob V. > > > > > Mike > > > 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00 > > > 88 Cherokee 235 BFG AT's > > > > > > c wrote: > > > > > > > > <averyislandboy@yahoo.com> wrote in message > > > > news:a188e6f3.0310081550.6c1b6b01@posting.google.c om... > > > > > Mike Romain <romainm@sympatico.ca> wrote in message > news:<3F83124C.E7063767@sympatico.ca>... > > > > > > Jut try tossing a 1/8 cup or a couple tablespoons of gas down the carb > > > > > > and see what happens. > > > > > > > > > > > > If it fires up, you have a hole in the gas line on the suction side of > > > > > > the pump or a dead pump that is letting the gas backflow to the tank or > > > > > > a torn diaphragm on the pump. > > > > > > > > > > The pump is brand new last month. > > > > > > > > > > > > > > > > > Does the oil on the dipstick smell like gas? > > > > > > > > > > nope smells like SAE 30 > > > > > > > > > > > > > > > > > Oh, the choke is an electric timer job. > > > > > > > > > > > > It will be totally closed after 5 minutes and opens according to how > > > > > > long 12 volts has been going to it. Piece of crap actually because it > > > > > > doesn't have a clue how hot or cold the engine really is, just how long > > > > > > it has had 12 volts. > > > > > > > > > > I don't think the choke is the prime offender since I tend to wedge it > > > > > open while trying to start it. > > > > > > > > > > > > > > > > > Mike > > > > > > > > > > Well, I actually took the plug wrench with me on a day that it acted > > > > > up. Which was totally out of the normal pattern because it was cold > > > > > and rainy. It also didn't start right up this morning, which is > > > > > atypical. It started a couple of times throughout the day, but when > > > > > it came to going home time it would not start. The engine was still > > > > > warm from having driven to the office from our pilot plant in the > > > > > previous 45 minutes or so. I cranked and cranked. Pumped the gas a > > > > > couple of times for giggles and cranked. No start. Aha! I have the > > > > > plug wrench, pulled out old number 1 and Voila, the plug, much to my > > > > > surprise was not wet. I could catch a faint whiff of petro when I put > > > > > it to my nose, but that's it. I don't think that that's classic > > > > > textbook flooded car "wet". So much for my theories to date. Not > > > > > having a remote starter (my wife wasn't at work with me, and the > > > > > cleaning lady had already gone home) I couldn't check if I had spark. > > > > > I scratched my head for a while, cranked it once with the plug hanging > > > > > over the alternator (not that I could even begin to see it from the > > > > > driver's seat. I didn't have a screwdriver to jump my solenoid, just > > > > > a 1/2" wrench and my socket driver which seemed like a bad idea on a > > > > > rainy day). So I put the plug back in, crank it and doggone it if it > > > > > doesn't start. Huh? Thankful (especially to Mike for encouraging me > > > > > to verify if it was flooded) and confused, I drive home brainstorming > > > > > new theories. > > > > > > > > > > What about if I had "weak spark"? I have checked the coil resistances > > > > > and it's good, but what if my starter and solenoid are getting "worn" > > > > > and sucking more juice than they should, that could drop the system > > > > > voltage pretty low and without 11-12V, would the coil work right? I'm > > > > > thinking about putting my spare battery in the passenger floor and > > > > > wiring it directly into the coil to ensure it is seeing 12V. Whacked > > > > > idea? Other suggestions? Like I've described, once the thing is > > > > > started it runs fine, but when it's running, the alternator is keeping > > > > > the coil at a happy 12-13V. > > > > > > > > OK, I might have a couple ideas here based on all the things I've read in > > > > this thread. First off, all of this is based on memory from what I've read, > > > > so bear with me if I repeat something you've tried. I remember you saying > > > > that when you pumped the accelerator after sitting, that the pump shot was > > > > good for a couple shots and then it "went dry". This seems wrong to me. You > > > > should get quite a few shots before the float bowl empties out. Definitely > > > > more than 2 or 3. This leads me to believe that either the float level is > > > > way too low, or possibly the fuel in the bowl is vaporizing from > > > > percolation, or both. A carb has more tendency to percolate when the float > > > > level is low because in essence the fuel cools the carburetor to some > > > > extent. Fuel percolation can also cause both flooded conditions and no fuel > > > > conditions, depending on how long the vehicle sits between starts. The fuel > > > > can sometimes percolate until the bowl is empty. The percolation can cause > > > > the fuel to siphon itself out of the carb through the fuel passages and into > > > > the engine. > > > > > > > > Also, regarding the fuel pump, just because it is new doesn't mean it is > > > > working properly. Try checking both volume and pressure. I'm not sure of the > > > > volume specs for your pump, but most of them are usually about a pint in > > > > 20-30 seconds of cranking. You'll have to check a service manual for your > > > > specs. I believe the fuel pressure should be between 4-6 PSI. Like Mike > > > > said, also check all of your fuel lines for pinholes. If the pump is sucking > > > > air instead of fuel, this can also lead to the percolation condition. The > > > > volume tests should reveal a suction problem as well. > > > > > > > > You may want to check the fuel you've been using. Maybe your gas station got > > > > some bad gas, or possibly they have mixed in that reconstituted crap. Some > > > > vehicles just flat won't run right on that stuff. > > > > > > > > As far as the spark being weak, I would say possible but not likely. Most > > > > factory coils "amplify" the voltage by a factor of about 1600 or more, which > > > > means that even with 8 volts going to the coil, you would have over 12000 > > > > volts going to the plugs. While this is not optimum, it will definitely fire > > > > a plug enough to start the engine. Remember, a lot of the old point systems > > > > had a ballast resistor in the ignition circuit to intentionally cut the > > > > voltage back while cranking. > > > > > > > > Chris |
Re: '88 YJ 258 ci with carter Hard Warm Start
" Stephen Cowell" <scowell@sbcglobal.net> wrote in message news:<PWHhb.722$ID5.164@newssvr23.news.prodigy.com >...
> <averyislandboy@yahoo.com> wrote in message > news:a188e6f3.0310101115.573f91e9@posting.google.c om... > ... > > The next step is to disconnect the suppressor. Well that's long gone, > > so I skip that step. > > You must like blowing up modules... that supressor is not > there just for good looks. > __ > Steve > . Seriously? I thought it was only to suppress RF frequencies that screw with radio reception. I bought the Jeep like that 2 years ago. No telling how long that thing's been gone. . . How sure are you about that? Bob |
Re: '88 YJ 258 ci with carter Hard Warm Start
" Stephen Cowell" <scowell@sbcglobal.net> wrote in message news:<PWHhb.722$ID5.164@newssvr23.news.prodigy.com >...
> <averyislandboy@yahoo.com> wrote in message > news:a188e6f3.0310101115.573f91e9@posting.google.c om... > ... > > The next step is to disconnect the suppressor. Well that's long gone, > > so I skip that step. > > You must like blowing up modules... that supressor is not > there just for good looks. > __ > Steve > . Seriously? I thought it was only to suppress RF frequencies that screw with radio reception. I bought the Jeep like that 2 years ago. No telling how long that thing's been gone. . . How sure are you about that? Bob |
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