DougW

nvrpc did pass the time by typing:
> I wrote off to Hayden and asked them for the part number of the clucth I
> desired. I hope to get an answer today sometime.
>
> On their web site these describe that the fan when cold should upon starting
> of the engine begine to turn very fast as if it was locked up and then slow
> down. My fan does not do that at all. It seems to always be moving the same
> speed regardless of engine RPM or temperature. I would prefer if it was
> locked up all of the time, but I will settle for lock up at 160 degrees.
>
> Wish me luck and if you have any more ideas or sugestions please let me
> know. Especially if there is a brand name preferance.

The fan is always going to turn at close to engine speed. What is different
is the amount of torque coupled to the fan through the fluid clutch.

The Mk-I eyeball is not capable of seeing this but if you have a timing
light/strobe you can.

Testing the fan clutch requires a thermometer, timing/strobe light,
and a bit of cardboard. You put the thermometer between the fan
and radiator to measure temp, use the cardboard to block off the
radiator (engine heats faster) then note at what temperature the
fan speed changes. Remove the cardboard and note the temp when
the fan slows down.

In my experience when a fan clutch goes the fan has almost
zero turning resistance when cold or hot or is solidly locked
up/rusted and has a scraping sound when you turn it.

Cold - medium resistance
Warm - low resistance
Hot - high resistance

--
DougW

DougW

nvrpc did pass the time by typing:
> I wrote off to Hayden and asked them for the part number of the clucth I
> desired. I hope to get an answer today sometime.
>
> On their web site these describe that the fan when cold should upon starting
> of the engine begine to turn very fast as if it was locked up and then slow
> down. My fan does not do that at all. It seems to always be moving the same
> speed regardless of engine RPM or temperature. I would prefer if it was
> locked up all of the time, but I will settle for lock up at 160 degrees.
>
> Wish me luck and if you have any more ideas or sugestions please let me
> know. Especially if there is a brand name preferance.

The fan is always going to turn at close to engine speed. What is different
is the amount of torque coupled to the fan through the fluid clutch.

The Mk-I eyeball is not capable of seeing this but if you have a timing
light/strobe you can.

Testing the fan clutch requires a thermometer, timing/strobe light,
and a bit of cardboard. You put the thermometer between the fan
and radiator to measure temp, use the cardboard to block off the
radiator (engine heats faster) then note at what temperature the
fan speed changes. Remove the cardboard and note the temp when
the fan slows down.

In my experience when a fan clutch goes the fan has almost
zero turning resistance when cold or hot or is solidly locked
up/rusted and has a scraping sound when you turn it.

Cold - medium resistance
Warm - low resistance
Hot - high resistance

--
DougW

DougW

nvrpc did pass the time by typing:
> I wrote off to Hayden and asked them for the part number of the clucth I
> desired. I hope to get an answer today sometime.
>
> On their web site these describe that the fan when cold should upon starting
> of the engine begine to turn very fast as if it was locked up and then slow
> down. My fan does not do that at all. It seems to always be moving the same
> speed regardless of engine RPM or temperature. I would prefer if it was
> locked up all of the time, but I will settle for lock up at 160 degrees.
>
> Wish me luck and if you have any more ideas or sugestions please let me
> know. Especially if there is a brand name preferance.

The fan is always going to turn at close to engine speed. What is different
is the amount of torque coupled to the fan through the fluid clutch.

The Mk-I eyeball is not capable of seeing this but if you have a timing
light/strobe you can.

Testing the fan clutch requires a thermometer, timing/strobe light,
and a bit of cardboard. You put the thermometer between the fan
and radiator to measure temp, use the cardboard to block off the
radiator (engine heats faster) then note at what temperature the
fan speed changes. Remove the cardboard and note the temp when
the fan slows down.

In my experience when a fan clutch goes the fan has almost
zero turning resistance when cold or hot or is solidly locked
up/rusted and has a scraping sound when you turn it.

Cold - medium resistance
Warm - low resistance
Hot - high resistance

--
DougW

Mike Romain

Holy crap!

Man how do you figure you will ever get those wheels off?

They should be torqued on around 100 ft lb max.

Your engine is designed to run at 210. I do not know any way to lower
it from that. The 4.0 engine runs at 210 also.

All that cold t-stat is going to do is to keep it in choke mode too long
and not allow any heat to the inside of the vehicle. But I guess having
no heater can be ok, depending on where you live.

The thermostat only controls how fast the engine heats up and how much
heat you have in the heater. It has no bearing on running.

A good fan clutch will stop when the engine is shut down hot. So you
can heat up the engine and have someone shut off the key while you watch
the fan. If the clutch is good, the hot fan stops. If it keeps on
spinning, the clutch is toast.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

nvrpc wrote:
>
> Okay. We got the new hubs on yesterady and torqued those nuts to 175 pond
> feet. Now I have another request. I currently have the stock fan clutch of
> which I hear will not kick in until 210 +. I want one that will kick in at
> 165 degrees. Doe anyone know where I can buy one. It seems that with AC the
> three core that I just put in will not keep the 258 cool enough. It still
> runs at ~ 210 when the outside air is 94 degrees. Water is flowing very well
> and I have a 165 thermosat in this vehicle.
>
> Well back to the cluch fan. Any ideas?

Mike Romain

Holy crap!

Man how do you figure you will ever get those wheels off?

They should be torqued on around 100 ft lb max.

Your engine is designed to run at 210. I do not know any way to lower
it from that. The 4.0 engine runs at 210 also.

All that cold t-stat is going to do is to keep it in choke mode too long
and not allow any heat to the inside of the vehicle. But I guess having
no heater can be ok, depending on where you live.

The thermostat only controls how fast the engine heats up and how much
heat you have in the heater. It has no bearing on running.

A good fan clutch will stop when the engine is shut down hot. So you
can heat up the engine and have someone shut off the key while you watch
the fan. If the clutch is good, the hot fan stops. If it keeps on
spinning, the clutch is toast.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

nvrpc wrote:
>
> Okay. We got the new hubs on yesterady and torqued those nuts to 175 pond
> feet. Now I have another request. I currently have the stock fan clutch of
> which I hear will not kick in until 210 +. I want one that will kick in at
> 165 degrees. Doe anyone know where I can buy one. It seems that with AC the
> three core that I just put in will not keep the 258 cool enough. It still
> runs at ~ 210 when the outside air is 94 degrees. Water is flowing very well
> and I have a 165 thermosat in this vehicle.
>
> Well back to the cluch fan. Any ideas?

Mike Romain

Holy crap!

Man how do you figure you will ever get those wheels off?

They should be torqued on around 100 ft lb max.

Your engine is designed to run at 210. I do not know any way to lower
it from that. The 4.0 engine runs at 210 also.

All that cold t-stat is going to do is to keep it in choke mode too long
and not allow any heat to the inside of the vehicle. But I guess having
no heater can be ok, depending on where you live.

The thermostat only controls how fast the engine heats up and how much
heat you have in the heater. It has no bearing on running.

A good fan clutch will stop when the engine is shut down hot. So you
can heat up the engine and have someone shut off the key while you watch
the fan. If the clutch is good, the hot fan stops. If it keeps on
spinning, the clutch is toast.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

nvrpc wrote:
>
> Okay. We got the new hubs on yesterady and torqued those nuts to 175 pond
> feet. Now I have another request. I currently have the stock fan clutch of
> which I hear will not kick in until 210 +. I want one that will kick in at
> 165 degrees. Doe anyone know where I can buy one. It seems that with AC the
> three core that I just put in will not keep the 258 cool enough. It still
> runs at ~ 210 when the outside air is 94 degrees. Water is flowing very well
> and I have a 165 thermosat in this vehicle.
>
> Well back to the cluch fan. Any ideas?

Mike Romain

Holy crap!

Man how do you figure you will ever get those wheels off?

They should be torqued on around 100 ft lb max.

Your engine is designed to run at 210. I do not know any way to lower
it from that. The 4.0 engine runs at 210 also.

All that cold t-stat is going to do is to keep it in choke mode too long
and not allow any heat to the inside of the vehicle. But I guess having
no heater can be ok, depending on where you live.

The thermostat only controls how fast the engine heats up and how much
heat you have in the heater. It has no bearing on running.

A good fan clutch will stop when the engine is shut down hot. So you
can heat up the engine and have someone shut off the key while you watch
the fan. If the clutch is good, the hot fan stops. If it keeps on
spinning, the clutch is toast.

Mike
86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
88 Cherokee 235 BFG AT's

nvrpc wrote:
>
> Okay. We got the new hubs on yesterady and torqued those nuts to 175 pond
> feet. Now I have another request. I currently have the stock fan clutch of
> which I hear will not kick in until 210 +. I want one that will kick in at
> 165 degrees. Doe anyone know where I can buy one. It seems that with AC the
> three core that I just put in will not keep the 258 cool enough. It still
> runs at ~ 210 when the outside air is 94 degrees. Water is flowing very well
> and I have a 165 thermosat in this vehicle.
>
> Well back to the cluch fan. Any ideas?

Roy J

Hubs go to 175ft/lbs WHEELS go to 100ft/lbs (He has the 1 piece hubs)

But like Mike says, the engine likes to run at around 200 for
fuel effieincy and driveability reasons.

I might point out that trying to get the engine to run at 160
with ambient at 94 only gives you 66 degrees of heat transfer
room. Takes a BIG radiator and small engine to be that
thermodynamically effiecient.

Mike Romain wrote:

> Holy crap!
>
> Man how do you figure you will ever get those wheels off?
>
> They should be torqued on around 100 ft lb max.
>
> Your engine is designed to run at 210. I do not know any way to lower
> it from that. The 4.0 engine runs at 210 also.
>
> All that cold t-stat is going to do is to keep it in choke mode too long
> and not allow any heat to the inside of the vehicle. But I guess having
> no heater can be ok, depending on where you live.
>
> The thermostat only controls how fast the engine heats up and how much
> heat you have in the heater. It has no bearing on running.
>
> A good fan clutch will stop when the engine is shut down hot. So you
> can heat up the engine and have someone shut off the key while you watch
> the fan. If the clutch is good, the hot fan stops. If it keeps on
> spinning, the clutch is toast.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> nvrpc wrote:
>
>>Okay. We got the new hubs on yesterady and torqued those nuts to 175 pond
>>feet. Now I have another request. I currently have the stock fan clutch of
>>which I hear will not kick in until 210 +. I want one that will kick in at
>>165 degrees. Doe anyone know where I can buy one. It seems that with AC the
>>three core that I just put in will not keep the 258 cool enough. It still
>>runs at ~ 210 when the outside air is 94 degrees. Water is flowing very well
>>and I have a 165 thermosat in this vehicle.
>>
>>Well back to the cluch fan. Any ideas?

Roy J

Hubs go to 175ft/lbs WHEELS go to 100ft/lbs (He has the 1 piece hubs)

But like Mike says, the engine likes to run at around 200 for
fuel effieincy and driveability reasons.

I might point out that trying to get the engine to run at 160
with ambient at 94 only gives you 66 degrees of heat transfer
room. Takes a BIG radiator and small engine to be that
thermodynamically effiecient.

Mike Romain wrote:

> Holy crap!
>
> Man how do you figure you will ever get those wheels off?
>
> They should be torqued on around 100 ft lb max.
>
> Your engine is designed to run at 210. I do not know any way to lower
> it from that. The 4.0 engine runs at 210 also.
>
> All that cold t-stat is going to do is to keep it in choke mode too long
> and not allow any heat to the inside of the vehicle. But I guess having
> no heater can be ok, depending on where you live.
>
> The thermostat only controls how fast the engine heats up and how much
> heat you have in the heater. It has no bearing on running.
>
> A good fan clutch will stop when the engine is shut down hot. So you
> can heat up the engine and have someone shut off the key while you watch
> the fan. If the clutch is good, the hot fan stops. If it keeps on
> spinning, the clutch is toast.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> nvrpc wrote:
>
>>Okay. We got the new hubs on yesterady and torqued those nuts to 175 pond
>>feet. Now I have another request. I currently have the stock fan clutch of
>>which I hear will not kick in until 210 +. I want one that will kick in at
>>165 degrees. Doe anyone know where I can buy one. It seems that with AC the
>>three core that I just put in will not keep the 258 cool enough. It still
>>runs at ~ 210 when the outside air is 94 degrees. Water is flowing very well
>>and I have a 165 thermosat in this vehicle.
>>
>>Well back to the cluch fan. Any ideas?

Roy J

Hubs go to 175ft/lbs WHEELS go to 100ft/lbs (He has the 1 piece hubs)

But like Mike says, the engine likes to run at around 200 for
fuel effieincy and driveability reasons.

I might point out that trying to get the engine to run at 160
with ambient at 94 only gives you 66 degrees of heat transfer
room. Takes a BIG radiator and small engine to be that
thermodynamically effiecient.

Mike Romain wrote:

> Holy crap!
>
> Man how do you figure you will ever get those wheels off?
>
> They should be torqued on around 100 ft lb max.
>
> Your engine is designed to run at 210. I do not know any way to lower
> it from that. The 4.0 engine runs at 210 also.
>
> All that cold t-stat is going to do is to keep it in choke mode too long
> and not allow any heat to the inside of the vehicle. But I guess having
> no heater can be ok, depending on where you live.
>
> The thermostat only controls how fast the engine heats up and how much
> heat you have in the heater. It has no bearing on running.
>
> A good fan clutch will stop when the engine is shut down hot. So you
> can heat up the engine and have someone shut off the key while you watch
> the fan. If the clutch is good, the hot fan stops. If it keeps on
> spinning, the clutch is toast.
>
> Mike
> 86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail in '00
> 88 Cherokee 235 BFG AT's
>
> nvrpc wrote:
>
>>Okay. We got the new hubs on yesterady and torqued those nuts to 175 pond
>>feet. Now I have another request. I currently have the stock fan clutch of
>>which I hear will not kick in until 210 +. I want one that will kick in at
>>165 degrees. Doe anyone know where I can buy one. It seems that with AC the
>>three core that I just put in will not keep the 258 cool enough. It still
>>runs at ~ 210 when the outside air is 94 degrees. Water is flowing very well
>>and I have a 165 thermosat in this vehicle.
>>
>>Well back to the cluch fan. Any ideas?