Followup-- 2000 JGC V-8 still overheating
01-14-2007, 12:30 PM
#101
Guest
Posts: n/a
Re: Re: Followup-- 2000 JGC V-8 still overheating
On Sun, 14 Jan 2007 11:31:11 -0500, Mike Romain <romainm@sympatico.ca>
wrote:
>He HAS done this! He has 'no' coolant flow with the rad cap off the
>rad!
Without chasing all wthe way back through thread has he checked for a
hose collapsed internally blocking flow?
-----------------
TheSnoMan.com
wrote:
>He HAS done this! He has 'no' coolant flow with the rad cap off the
>rad!
Without chasing all wthe way back through thread has he checked for a
hose collapsed internally blocking flow?
-----------------
TheSnoMan.com
01-14-2007, 12:36 PM
#102
Guest
Posts: n/a
Re: Followup-- 2000 JGC V-8 still overheating
Mike, it is the original water pump. SnoMan, yes, the fan does run at
idle, with temp at 205.
Yes, I do have tow package, and the coolant is full. It is up to the very
top of the neck when I take the rad cap off. There is NO circulation of
the coolant, and it is warm, but not really HOT, even when the gauge is at
205.
I think my next step is to take it to a rad shop and allow them to take the
rad out and test it.
Yes, I could have another "bad" (new) thermostat, but I don't know how
many times I should try that. (I am not a mechanic, so I can't do that
myself, so I have to leave it for a day when I have work done).
Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
it is a water pump or fan clutch problem. Could be another bad thermostat,
OR a flow problem in the rad system.
It just seems to me that if the car does fine at idle (can run all day
at a redlight and not heat up), but heats some at 75mph and heats a LOT on
long incline, no enough coolant is circulating around the engine. Again,
this is just from a "lay" person.
I do appreciate all of the comments though, thank you all!!
--James--
idle, with temp at 205.
Yes, I do have tow package, and the coolant is full. It is up to the very
top of the neck when I take the rad cap off. There is NO circulation of
the coolant, and it is warm, but not really HOT, even when the gauge is at
205.
I think my next step is to take it to a rad shop and allow them to take the
rad out and test it.
Yes, I could have another "bad" (new) thermostat, but I don't know how
many times I should try that. (I am not a mechanic, so I can't do that
myself, so I have to leave it for a day when I have work done).
Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
it is a water pump or fan clutch problem. Could be another bad thermostat,
OR a flow problem in the rad system.
It just seems to me that if the car does fine at idle (can run all day
at a redlight and not heat up), but heats some at 75mph and heats a LOT on
long incline, no enough coolant is circulating around the engine. Again,
this is just from a "lay" person.
I do appreciate all of the comments though, thank you all!!
--James--
01-14-2007, 12:36 PM
#103
Guest
Posts: n/a
Re: Followup-- 2000 JGC V-8 still overheating
Mike, it is the original water pump. SnoMan, yes, the fan does run at
idle, with temp at 205.
Yes, I do have tow package, and the coolant is full. It is up to the very
top of the neck when I take the rad cap off. There is NO circulation of
the coolant, and it is warm, but not really HOT, even when the gauge is at
205.
I think my next step is to take it to a rad shop and allow them to take the
rad out and test it.
Yes, I could have another "bad" (new) thermostat, but I don't know how
many times I should try that. (I am not a mechanic, so I can't do that
myself, so I have to leave it for a day when I have work done).
Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
it is a water pump or fan clutch problem. Could be another bad thermostat,
OR a flow problem in the rad system.
It just seems to me that if the car does fine at idle (can run all day
at a redlight and not heat up), but heats some at 75mph and heats a LOT on
long incline, no enough coolant is circulating around the engine. Again,
this is just from a "lay" person.
I do appreciate all of the comments though, thank you all!!
--James--
idle, with temp at 205.
Yes, I do have tow package, and the coolant is full. It is up to the very
top of the neck when I take the rad cap off. There is NO circulation of
the coolant, and it is warm, but not really HOT, even when the gauge is at
205.
I think my next step is to take it to a rad shop and allow them to take the
rad out and test it.
Yes, I could have another "bad" (new) thermostat, but I don't know how
many times I should try that. (I am not a mechanic, so I can't do that
myself, so I have to leave it for a day when I have work done).
Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
it is a water pump or fan clutch problem. Could be another bad thermostat,
OR a flow problem in the rad system.
It just seems to me that if the car does fine at idle (can run all day
at a redlight and not heat up), but heats some at 75mph and heats a LOT on
long incline, no enough coolant is circulating around the engine. Again,
this is just from a "lay" person.
I do appreciate all of the comments though, thank you all!!
--James--
01-14-2007, 12:36 PM
#104
Guest
Posts: n/a
Re: Followup-- 2000 JGC V-8 still overheating
Mike, it is the original water pump. SnoMan, yes, the fan does run at
idle, with temp at 205.
Yes, I do have tow package, and the coolant is full. It is up to the very
top of the neck when I take the rad cap off. There is NO circulation of
the coolant, and it is warm, but not really HOT, even when the gauge is at
205.
I think my next step is to take it to a rad shop and allow them to take the
rad out and test it.
Yes, I could have another "bad" (new) thermostat, but I don't know how
many times I should try that. (I am not a mechanic, so I can't do that
myself, so I have to leave it for a day when I have work done).
Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
it is a water pump or fan clutch problem. Could be another bad thermostat,
OR a flow problem in the rad system.
It just seems to me that if the car does fine at idle (can run all day
at a redlight and not heat up), but heats some at 75mph and heats a LOT on
long incline, no enough coolant is circulating around the engine. Again,
this is just from a "lay" person.
I do appreciate all of the comments though, thank you all!!
--James--
idle, with temp at 205.
Yes, I do have tow package, and the coolant is full. It is up to the very
top of the neck when I take the rad cap off. There is NO circulation of
the coolant, and it is warm, but not really HOT, even when the gauge is at
205.
I think my next step is to take it to a rad shop and allow them to take the
rad out and test it.
Yes, I could have another "bad" (new) thermostat, but I don't know how
many times I should try that. (I am not a mechanic, so I can't do that
myself, so I have to leave it for a day when I have work done).
Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
it is a water pump or fan clutch problem. Could be another bad thermostat,
OR a flow problem in the rad system.
It just seems to me that if the car does fine at idle (can run all day
at a redlight and not heat up), but heats some at 75mph and heats a LOT on
long incline, no enough coolant is circulating around the engine. Again,
this is just from a "lay" person.
I do appreciate all of the comments though, thank you all!!
--James--
01-14-2007, 12:36 PM
#105
Guest
Posts: n/a
Re: Followup-- 2000 JGC V-8 still overheating
Mike, it is the original water pump. SnoMan, yes, the fan does run at
idle, with temp at 205.
Yes, I do have tow package, and the coolant is full. It is up to the very
top of the neck when I take the rad cap off. There is NO circulation of
the coolant, and it is warm, but not really HOT, even when the gauge is at
205.
I think my next step is to take it to a rad shop and allow them to take the
rad out and test it.
Yes, I could have another "bad" (new) thermostat, but I don't know how
many times I should try that. (I am not a mechanic, so I can't do that
myself, so I have to leave it for a day when I have work done).
Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
it is a water pump or fan clutch problem. Could be another bad thermostat,
OR a flow problem in the rad system.
It just seems to me that if the car does fine at idle (can run all day
at a redlight and not heat up), but heats some at 75mph and heats a LOT on
long incline, no enough coolant is circulating around the engine. Again,
this is just from a "lay" person.
I do appreciate all of the comments though, thank you all!!
--James--
idle, with temp at 205.
Yes, I do have tow package, and the coolant is full. It is up to the very
top of the neck when I take the rad cap off. There is NO circulation of
the coolant, and it is warm, but not really HOT, even when the gauge is at
205.
I think my next step is to take it to a rad shop and allow them to take the
rad out and test it.
Yes, I could have another "bad" (new) thermostat, but I don't know how
many times I should try that. (I am not a mechanic, so I can't do that
myself, so I have to leave it for a day when I have work done).
Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
it is a water pump or fan clutch problem. Could be another bad thermostat,
OR a flow problem in the rad system.
It just seems to me that if the car does fine at idle (can run all day
at a redlight and not heat up), but heats some at 75mph and heats a LOT on
long incline, no enough coolant is circulating around the engine. Again,
this is just from a "lay" person.
I do appreciate all of the comments though, thank you all!!
--James--
01-14-2007, 02:33 PM
#106
Guest
Posts: n/a
Re: Followup-- 2000 JGC V-8 still overheating
On Sun, 14 Jan 2007 12:36:16 -0500, "James" <jnipperxxx@nospamfdn.com>
wrote:
>Mike, it is the original water pump. SnoMan, yes, the fan does run at
>idle, with temp at 205.
>
>Yes, I do have tow package, and the coolant is full. It is up to the very
>top of the neck when I take the rad cap off. There is NO circulation of
>the coolant, and it is warm, but not really HOT, even when the gauge is at
>205.
>
>I think my next step is to take it to a rad shop and allow them to take the
>rad out and test it.
>
>Yes, I could have another "bad" (new) thermostat, but I don't know how
>many times I should try that. (I am not a mechanic, so I can't do that
>myself, so I have to leave it for a day when I have work done).
>
>Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
>it is a water pump or fan clutch problem. Could be another bad thermostat,
>OR a flow problem in the rad system.
>
>
> It just seems to me that if the car does fine at idle (can run all day
>at a redlight and not heat up), but heats some at 75mph and heats a LOT on
>long incline, no enough coolant is circulating around the engine. Again,
>this is just from a "lay" person.
>
>I do appreciate all of the comments though, thank you all!!
>
>
>--James--
>
I just made a call to a buddy in the OEM automotive thermostat
business who knows the T' Stat technical part pretty well, maybe he'll
join in.
Talking to him ... he recalls that the 4,7 has an Inlet Side T' Stat -
meaning that it controls the flow of coolant back into the engine from
the radiator. This contrasts with typical / conventional T' Stats
which control the flow leaving the engine.
Chrysler had some issues with the Front Cover in '99 and 2000 when the
4.7 was first introduced. The front cover mixes coolant circulating
from the block with coolant coming back from the radiator. This mixed
temperature is what the T' Stat sees and increases or decreases the
amount coming from the Radiator (there are lots of good reasons why an
inlet side T' Stat is a good idea). The problem that DCX had was that
this mixing volume in the front cover didn't quite work right and some
owners had problems from day one ... I believe the fix involved
replacing the front cover which isn't a simple job on this integrated
accessory drive motor.
With this inlet side T' Stat control the diagnostic logic isn't the
same as on conventional T' Stat engines - such as when a T' Stat is
installed backwards.
Regarding the coolant flow problem open cap at warm idle - if the
coolant is warm there is some flow taking place - simple physics. That
you cannot feel or see this flow means it is very low - and, since
this is a cross-flow radiator you don't see flow across an upper
radiator header like you would in a down-flow radiator. The radiator
inlet connection is down part way on the inlet tank and the flow goes
through the radiator core, most not seeing the light of day when
looking in the filler neck.
I just called another buddy about the fan system on this car - the
difference between trailer tow and non-trailer two configuration... he
worked on the fan system when he worked for Delco in the time frame.
He says that the JGC needs to have the engine driven fan operating at
highway speeds, that the ram air alone wasn't sufficient to keep the
coolant temperature controlled by the T' Stat.
The conventional (non trailer tow) system has an electric fan on the
engine side of the radiator inside the shroud (with enough power to
make the condenser work in air conditioning) and a engine driven fan
with a Delco fan clutch. This fan clutch was engineered for very low
drag - meaning that unless the bi-metal kicked it in the fan turned at
a low speed - you can stop the fan at idle with a pencil. Even kicked
in the fan clutch wasn't a real high torque clutch.
The trailer tow system was similar - an electric fan behind the
radiator and an engine driven Delco 1525 fan clutch with a higher
torque rating.
Your system is acting 'cooling limited' in that the coolant
temperature is a function of engine load. There are two possible
causes for this in the first breakdown.
- low coolant flow (as from an internally restricted radiator or a
collapsed coolant return hose
- low airflow with two possible causes
- blocked air path (bugs, mud, bent fins, airside corrosion
- inoperative fan
The blocked air path can be determined by looking at it - is the
condenser covered with dead bugs, do you have a bug screen, is it or
the radiator plugged up with dried mud (clay gets like concrete) or is
there a lot of white 'fuzz' corrosion on the louvers in the fins. If
it is bugs or mud you can clean it with a garden hose, don't use a
pressure washer or you'll fold the fins over and need to replace the
heat exchanger.
The inoperative fan can be checked this way - dig out the RTV holding
the leg of the bi-metal coil in position and lift it over the boss on
the clutch cover and rotate it counter-clockwise, let it rest against
the boss from the other side. This will leave the fan always engaged.
After driving the car to fully warm shut off the engine and see if
there is significant drag when you try to rotate the fan by hand. If
it spins pretty easily then the clutch is out of fluid and needs to be
replaced. If there is drag and the cooling problem goes away you need
to replace the clutch. If there is drag and the cooling problem
hasn't gone away then it is either problem with bugs / mud or internal
restriction on the coolant side of the radiator.
I would try the fan clutch bi-metal coil first - it doesn't cost
anything, its easy and it doesn't risk screwing anything up ...
reboot
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wrote:
>Mike, it is the original water pump. SnoMan, yes, the fan does run at
>idle, with temp at 205.
>
>Yes, I do have tow package, and the coolant is full. It is up to the very
>top of the neck when I take the rad cap off. There is NO circulation of
>the coolant, and it is warm, but not really HOT, even when the gauge is at
>205.
>
>I think my next step is to take it to a rad shop and allow them to take the
>rad out and test it.
>
>Yes, I could have another "bad" (new) thermostat, but I don't know how
>many times I should try that. (I am not a mechanic, so I can't do that
>myself, so I have to leave it for a day when I have work done).
>
>Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
>it is a water pump or fan clutch problem. Could be another bad thermostat,
>OR a flow problem in the rad system.
>
>
> It just seems to me that if the car does fine at idle (can run all day
>at a redlight and not heat up), but heats some at 75mph and heats a LOT on
>long incline, no enough coolant is circulating around the engine. Again,
>this is just from a "lay" person.
>
>I do appreciate all of the comments though, thank you all!!
>
>
>--James--
>
I just made a call to a buddy in the OEM automotive thermostat
business who knows the T' Stat technical part pretty well, maybe he'll
join in.
Talking to him ... he recalls that the 4,7 has an Inlet Side T' Stat -
meaning that it controls the flow of coolant back into the engine from
the radiator. This contrasts with typical / conventional T' Stats
which control the flow leaving the engine.
Chrysler had some issues with the Front Cover in '99 and 2000 when the
4.7 was first introduced. The front cover mixes coolant circulating
from the block with coolant coming back from the radiator. This mixed
temperature is what the T' Stat sees and increases or decreases the
amount coming from the Radiator (there are lots of good reasons why an
inlet side T' Stat is a good idea). The problem that DCX had was that
this mixing volume in the front cover didn't quite work right and some
owners had problems from day one ... I believe the fix involved
replacing the front cover which isn't a simple job on this integrated
accessory drive motor.
With this inlet side T' Stat control the diagnostic logic isn't the
same as on conventional T' Stat engines - such as when a T' Stat is
installed backwards.
Regarding the coolant flow problem open cap at warm idle - if the
coolant is warm there is some flow taking place - simple physics. That
you cannot feel or see this flow means it is very low - and, since
this is a cross-flow radiator you don't see flow across an upper
radiator header like you would in a down-flow radiator. The radiator
inlet connection is down part way on the inlet tank and the flow goes
through the radiator core, most not seeing the light of day when
looking in the filler neck.
I just called another buddy about the fan system on this car - the
difference between trailer tow and non-trailer two configuration... he
worked on the fan system when he worked for Delco in the time frame.
He says that the JGC needs to have the engine driven fan operating at
highway speeds, that the ram air alone wasn't sufficient to keep the
coolant temperature controlled by the T' Stat.
The conventional (non trailer tow) system has an electric fan on the
engine side of the radiator inside the shroud (with enough power to
make the condenser work in air conditioning) and a engine driven fan
with a Delco fan clutch. This fan clutch was engineered for very low
drag - meaning that unless the bi-metal kicked it in the fan turned at
a low speed - you can stop the fan at idle with a pencil. Even kicked
in the fan clutch wasn't a real high torque clutch.
The trailer tow system was similar - an electric fan behind the
radiator and an engine driven Delco 1525 fan clutch with a higher
torque rating.
Your system is acting 'cooling limited' in that the coolant
temperature is a function of engine load. There are two possible
causes for this in the first breakdown.
- low coolant flow (as from an internally restricted radiator or a
collapsed coolant return hose
- low airflow with two possible causes
- blocked air path (bugs, mud, bent fins, airside corrosion
- inoperative fan
The blocked air path can be determined by looking at it - is the
condenser covered with dead bugs, do you have a bug screen, is it or
the radiator plugged up with dried mud (clay gets like concrete) or is
there a lot of white 'fuzz' corrosion on the louvers in the fins. If
it is bugs or mud you can clean it with a garden hose, don't use a
pressure washer or you'll fold the fins over and need to replace the
heat exchanger.
The inoperative fan can be checked this way - dig out the RTV holding
the leg of the bi-metal coil in position and lift it over the boss on
the clutch cover and rotate it counter-clockwise, let it rest against
the boss from the other side. This will leave the fan always engaged.
After driving the car to fully warm shut off the engine and see if
there is significant drag when you try to rotate the fan by hand. If
it spins pretty easily then the clutch is out of fluid and needs to be
replaced. If there is drag and the cooling problem goes away you need
to replace the clutch. If there is drag and the cooling problem
hasn't gone away then it is either problem with bugs / mud or internal
restriction on the coolant side of the radiator.
I would try the fan clutch bi-metal coil first - it doesn't cost
anything, its easy and it doesn't risk screwing anything up ...
reboot
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Tested on: 1/14/2007 2:33:26 PM
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01-14-2007, 02:33 PM
#107
Guest
Posts: n/a
Re: Followup-- 2000 JGC V-8 still overheating
On Sun, 14 Jan 2007 12:36:16 -0500, "James" <jnipperxxx@nospamfdn.com>
wrote:
>Mike, it is the original water pump. SnoMan, yes, the fan does run at
>idle, with temp at 205.
>
>Yes, I do have tow package, and the coolant is full. It is up to the very
>top of the neck when I take the rad cap off. There is NO circulation of
>the coolant, and it is warm, but not really HOT, even when the gauge is at
>205.
>
>I think my next step is to take it to a rad shop and allow them to take the
>rad out and test it.
>
>Yes, I could have another "bad" (new) thermostat, but I don't know how
>many times I should try that. (I am not a mechanic, so I can't do that
>myself, so I have to leave it for a day when I have work done).
>
>Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
>it is a water pump or fan clutch problem. Could be another bad thermostat,
>OR a flow problem in the rad system.
>
>
> It just seems to me that if the car does fine at idle (can run all day
>at a redlight and not heat up), but heats some at 75mph and heats a LOT on
>long incline, no enough coolant is circulating around the engine. Again,
>this is just from a "lay" person.
>
>I do appreciate all of the comments though, thank you all!!
>
>
>--James--
>
I just made a call to a buddy in the OEM automotive thermostat
business who knows the T' Stat technical part pretty well, maybe he'll
join in.
Talking to him ... he recalls that the 4,7 has an Inlet Side T' Stat -
meaning that it controls the flow of coolant back into the engine from
the radiator. This contrasts with typical / conventional T' Stats
which control the flow leaving the engine.
Chrysler had some issues with the Front Cover in '99 and 2000 when the
4.7 was first introduced. The front cover mixes coolant circulating
from the block with coolant coming back from the radiator. This mixed
temperature is what the T' Stat sees and increases or decreases the
amount coming from the Radiator (there are lots of good reasons why an
inlet side T' Stat is a good idea). The problem that DCX had was that
this mixing volume in the front cover didn't quite work right and some
owners had problems from day one ... I believe the fix involved
replacing the front cover which isn't a simple job on this integrated
accessory drive motor.
With this inlet side T' Stat control the diagnostic logic isn't the
same as on conventional T' Stat engines - such as when a T' Stat is
installed backwards.
Regarding the coolant flow problem open cap at warm idle - if the
coolant is warm there is some flow taking place - simple physics. That
you cannot feel or see this flow means it is very low - and, since
this is a cross-flow radiator you don't see flow across an upper
radiator header like you would in a down-flow radiator. The radiator
inlet connection is down part way on the inlet tank and the flow goes
through the radiator core, most not seeing the light of day when
looking in the filler neck.
I just called another buddy about the fan system on this car - the
difference between trailer tow and non-trailer two configuration... he
worked on the fan system when he worked for Delco in the time frame.
He says that the JGC needs to have the engine driven fan operating at
highway speeds, that the ram air alone wasn't sufficient to keep the
coolant temperature controlled by the T' Stat.
The conventional (non trailer tow) system has an electric fan on the
engine side of the radiator inside the shroud (with enough power to
make the condenser work in air conditioning) and a engine driven fan
with a Delco fan clutch. This fan clutch was engineered for very low
drag - meaning that unless the bi-metal kicked it in the fan turned at
a low speed - you can stop the fan at idle with a pencil. Even kicked
in the fan clutch wasn't a real high torque clutch.
The trailer tow system was similar - an electric fan behind the
radiator and an engine driven Delco 1525 fan clutch with a higher
torque rating.
Your system is acting 'cooling limited' in that the coolant
temperature is a function of engine load. There are two possible
causes for this in the first breakdown.
- low coolant flow (as from an internally restricted radiator or a
collapsed coolant return hose
- low airflow with two possible causes
- blocked air path (bugs, mud, bent fins, airside corrosion
- inoperative fan
The blocked air path can be determined by looking at it - is the
condenser covered with dead bugs, do you have a bug screen, is it or
the radiator plugged up with dried mud (clay gets like concrete) or is
there a lot of white 'fuzz' corrosion on the louvers in the fins. If
it is bugs or mud you can clean it with a garden hose, don't use a
pressure washer or you'll fold the fins over and need to replace the
heat exchanger.
The inoperative fan can be checked this way - dig out the RTV holding
the leg of the bi-metal coil in position and lift it over the boss on
the clutch cover and rotate it counter-clockwise, let it rest against
the boss from the other side. This will leave the fan always engaged.
After driving the car to fully warm shut off the engine and see if
there is significant drag when you try to rotate the fan by hand. If
it spins pretty easily then the clutch is out of fluid and needs to be
replaced. If there is drag and the cooling problem goes away you need
to replace the clutch. If there is drag and the cooling problem
hasn't gone away then it is either problem with bugs / mud or internal
restriction on the coolant side of the radiator.
I would try the fan clutch bi-metal coil first - it doesn't cost
anything, its easy and it doesn't risk screwing anything up ...
reboot
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Virus Database (VPS): 0703-0, 01/13/2007
Tested on: 1/14/2007 2:33:26 PM
avast! - copyright (c) 1988-2007 ALWIL Software.
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wrote:
>Mike, it is the original water pump. SnoMan, yes, the fan does run at
>idle, with temp at 205.
>
>Yes, I do have tow package, and the coolant is full. It is up to the very
>top of the neck when I take the rad cap off. There is NO circulation of
>the coolant, and it is warm, but not really HOT, even when the gauge is at
>205.
>
>I think my next step is to take it to a rad shop and allow them to take the
>rad out and test it.
>
>Yes, I could have another "bad" (new) thermostat, but I don't know how
>many times I should try that. (I am not a mechanic, so I can't do that
>myself, so I have to leave it for a day when I have work done).
>
>Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
>it is a water pump or fan clutch problem. Could be another bad thermostat,
>OR a flow problem in the rad system.
>
>
> It just seems to me that if the car does fine at idle (can run all day
>at a redlight and not heat up), but heats some at 75mph and heats a LOT on
>long incline, no enough coolant is circulating around the engine. Again,
>this is just from a "lay" person.
>
>I do appreciate all of the comments though, thank you all!!
>
>
>--James--
>
I just made a call to a buddy in the OEM automotive thermostat
business who knows the T' Stat technical part pretty well, maybe he'll
join in.
Talking to him ... he recalls that the 4,7 has an Inlet Side T' Stat -
meaning that it controls the flow of coolant back into the engine from
the radiator. This contrasts with typical / conventional T' Stats
which control the flow leaving the engine.
Chrysler had some issues with the Front Cover in '99 and 2000 when the
4.7 was first introduced. The front cover mixes coolant circulating
from the block with coolant coming back from the radiator. This mixed
temperature is what the T' Stat sees and increases or decreases the
amount coming from the Radiator (there are lots of good reasons why an
inlet side T' Stat is a good idea). The problem that DCX had was that
this mixing volume in the front cover didn't quite work right and some
owners had problems from day one ... I believe the fix involved
replacing the front cover which isn't a simple job on this integrated
accessory drive motor.
With this inlet side T' Stat control the diagnostic logic isn't the
same as on conventional T' Stat engines - such as when a T' Stat is
installed backwards.
Regarding the coolant flow problem open cap at warm idle - if the
coolant is warm there is some flow taking place - simple physics. That
you cannot feel or see this flow means it is very low - and, since
this is a cross-flow radiator you don't see flow across an upper
radiator header like you would in a down-flow radiator. The radiator
inlet connection is down part way on the inlet tank and the flow goes
through the radiator core, most not seeing the light of day when
looking in the filler neck.
I just called another buddy about the fan system on this car - the
difference between trailer tow and non-trailer two configuration... he
worked on the fan system when he worked for Delco in the time frame.
He says that the JGC needs to have the engine driven fan operating at
highway speeds, that the ram air alone wasn't sufficient to keep the
coolant temperature controlled by the T' Stat.
The conventional (non trailer tow) system has an electric fan on the
engine side of the radiator inside the shroud (with enough power to
make the condenser work in air conditioning) and a engine driven fan
with a Delco fan clutch. This fan clutch was engineered for very low
drag - meaning that unless the bi-metal kicked it in the fan turned at
a low speed - you can stop the fan at idle with a pencil. Even kicked
in the fan clutch wasn't a real high torque clutch.
The trailer tow system was similar - an electric fan behind the
radiator and an engine driven Delco 1525 fan clutch with a higher
torque rating.
Your system is acting 'cooling limited' in that the coolant
temperature is a function of engine load. There are two possible
causes for this in the first breakdown.
- low coolant flow (as from an internally restricted radiator or a
collapsed coolant return hose
- low airflow with two possible causes
- blocked air path (bugs, mud, bent fins, airside corrosion
- inoperative fan
The blocked air path can be determined by looking at it - is the
condenser covered with dead bugs, do you have a bug screen, is it or
the radiator plugged up with dried mud (clay gets like concrete) or is
there a lot of white 'fuzz' corrosion on the louvers in the fins. If
it is bugs or mud you can clean it with a garden hose, don't use a
pressure washer or you'll fold the fins over and need to replace the
heat exchanger.
The inoperative fan can be checked this way - dig out the RTV holding
the leg of the bi-metal coil in position and lift it over the boss on
the clutch cover and rotate it counter-clockwise, let it rest against
the boss from the other side. This will leave the fan always engaged.
After driving the car to fully warm shut off the engine and see if
there is significant drag when you try to rotate the fan by hand. If
it spins pretty easily then the clutch is out of fluid and needs to be
replaced. If there is drag and the cooling problem goes away you need
to replace the clutch. If there is drag and the cooling problem
hasn't gone away then it is either problem with bugs / mud or internal
restriction on the coolant side of the radiator.
I would try the fan clutch bi-metal coil first - it doesn't cost
anything, its easy and it doesn't risk screwing anything up ...
reboot
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01-14-2007, 02:33 PM
#108
Guest
Posts: n/a
Re: Followup-- 2000 JGC V-8 still overheating
On Sun, 14 Jan 2007 12:36:16 -0500, "James" <jnipperxxx@nospamfdn.com>
wrote:
>Mike, it is the original water pump. SnoMan, yes, the fan does run at
>idle, with temp at 205.
>
>Yes, I do have tow package, and the coolant is full. It is up to the very
>top of the neck when I take the rad cap off. There is NO circulation of
>the coolant, and it is warm, but not really HOT, even when the gauge is at
>205.
>
>I think my next step is to take it to a rad shop and allow them to take the
>rad out and test it.
>
>Yes, I could have another "bad" (new) thermostat, but I don't know how
>many times I should try that. (I am not a mechanic, so I can't do that
>myself, so I have to leave it for a day when I have work done).
>
>Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
>it is a water pump or fan clutch problem. Could be another bad thermostat,
>OR a flow problem in the rad system.
>
>
> It just seems to me that if the car does fine at idle (can run all day
>at a redlight and not heat up), but heats some at 75mph and heats a LOT on
>long incline, no enough coolant is circulating around the engine. Again,
>this is just from a "lay" person.
>
>I do appreciate all of the comments though, thank you all!!
>
>
>--James--
>
I just made a call to a buddy in the OEM automotive thermostat
business who knows the T' Stat technical part pretty well, maybe he'll
join in.
Talking to him ... he recalls that the 4,7 has an Inlet Side T' Stat -
meaning that it controls the flow of coolant back into the engine from
the radiator. This contrasts with typical / conventional T' Stats
which control the flow leaving the engine.
Chrysler had some issues with the Front Cover in '99 and 2000 when the
4.7 was first introduced. The front cover mixes coolant circulating
from the block with coolant coming back from the radiator. This mixed
temperature is what the T' Stat sees and increases or decreases the
amount coming from the Radiator (there are lots of good reasons why an
inlet side T' Stat is a good idea). The problem that DCX had was that
this mixing volume in the front cover didn't quite work right and some
owners had problems from day one ... I believe the fix involved
replacing the front cover which isn't a simple job on this integrated
accessory drive motor.
With this inlet side T' Stat control the diagnostic logic isn't the
same as on conventional T' Stat engines - such as when a T' Stat is
installed backwards.
Regarding the coolant flow problem open cap at warm idle - if the
coolant is warm there is some flow taking place - simple physics. That
you cannot feel or see this flow means it is very low - and, since
this is a cross-flow radiator you don't see flow across an upper
radiator header like you would in a down-flow radiator. The radiator
inlet connection is down part way on the inlet tank and the flow goes
through the radiator core, most not seeing the light of day when
looking in the filler neck.
I just called another buddy about the fan system on this car - the
difference between trailer tow and non-trailer two configuration... he
worked on the fan system when he worked for Delco in the time frame.
He says that the JGC needs to have the engine driven fan operating at
highway speeds, that the ram air alone wasn't sufficient to keep the
coolant temperature controlled by the T' Stat.
The conventional (non trailer tow) system has an electric fan on the
engine side of the radiator inside the shroud (with enough power to
make the condenser work in air conditioning) and a engine driven fan
with a Delco fan clutch. This fan clutch was engineered for very low
drag - meaning that unless the bi-metal kicked it in the fan turned at
a low speed - you can stop the fan at idle with a pencil. Even kicked
in the fan clutch wasn't a real high torque clutch.
The trailer tow system was similar - an electric fan behind the
radiator and an engine driven Delco 1525 fan clutch with a higher
torque rating.
Your system is acting 'cooling limited' in that the coolant
temperature is a function of engine load. There are two possible
causes for this in the first breakdown.
- low coolant flow (as from an internally restricted radiator or a
collapsed coolant return hose
- low airflow with two possible causes
- blocked air path (bugs, mud, bent fins, airside corrosion
- inoperative fan
The blocked air path can be determined by looking at it - is the
condenser covered with dead bugs, do you have a bug screen, is it or
the radiator plugged up with dried mud (clay gets like concrete) or is
there a lot of white 'fuzz' corrosion on the louvers in the fins. If
it is bugs or mud you can clean it with a garden hose, don't use a
pressure washer or you'll fold the fins over and need to replace the
heat exchanger.
The inoperative fan can be checked this way - dig out the RTV holding
the leg of the bi-metal coil in position and lift it over the boss on
the clutch cover and rotate it counter-clockwise, let it rest against
the boss from the other side. This will leave the fan always engaged.
After driving the car to fully warm shut off the engine and see if
there is significant drag when you try to rotate the fan by hand. If
it spins pretty easily then the clutch is out of fluid and needs to be
replaced. If there is drag and the cooling problem goes away you need
to replace the clutch. If there is drag and the cooling problem
hasn't gone away then it is either problem with bugs / mud or internal
restriction on the coolant side of the radiator.
I would try the fan clutch bi-metal coil first - it doesn't cost
anything, its easy and it doesn't risk screwing anything up ...
reboot
---
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Virus Database (VPS): 0703-0, 01/13/2007
Tested on: 1/14/2007 2:33:26 PM
avast! - copyright (c) 1988-2007 ALWIL Software.
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wrote:
>Mike, it is the original water pump. SnoMan, yes, the fan does run at
>idle, with temp at 205.
>
>Yes, I do have tow package, and the coolant is full. It is up to the very
>top of the neck when I take the rad cap off. There is NO circulation of
>the coolant, and it is warm, but not really HOT, even when the gauge is at
>205.
>
>I think my next step is to take it to a rad shop and allow them to take the
>rad out and test it.
>
>Yes, I could have another "bad" (new) thermostat, but I don't know how
>many times I should try that. (I am not a mechanic, so I can't do that
>myself, so I have to leave it for a day when I have work done).
>
>Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
>it is a water pump or fan clutch problem. Could be another bad thermostat,
>OR a flow problem in the rad system.
>
>
> It just seems to me that if the car does fine at idle (can run all day
>at a redlight and not heat up), but heats some at 75mph and heats a LOT on
>long incline, no enough coolant is circulating around the engine. Again,
>this is just from a "lay" person.
>
>I do appreciate all of the comments though, thank you all!!
>
>
>--James--
>
I just made a call to a buddy in the OEM automotive thermostat
business who knows the T' Stat technical part pretty well, maybe he'll
join in.
Talking to him ... he recalls that the 4,7 has an Inlet Side T' Stat -
meaning that it controls the flow of coolant back into the engine from
the radiator. This contrasts with typical / conventional T' Stats
which control the flow leaving the engine.
Chrysler had some issues with the Front Cover in '99 and 2000 when the
4.7 was first introduced. The front cover mixes coolant circulating
from the block with coolant coming back from the radiator. This mixed
temperature is what the T' Stat sees and increases or decreases the
amount coming from the Radiator (there are lots of good reasons why an
inlet side T' Stat is a good idea). The problem that DCX had was that
this mixing volume in the front cover didn't quite work right and some
owners had problems from day one ... I believe the fix involved
replacing the front cover which isn't a simple job on this integrated
accessory drive motor.
With this inlet side T' Stat control the diagnostic logic isn't the
same as on conventional T' Stat engines - such as when a T' Stat is
installed backwards.
Regarding the coolant flow problem open cap at warm idle - if the
coolant is warm there is some flow taking place - simple physics. That
you cannot feel or see this flow means it is very low - and, since
this is a cross-flow radiator you don't see flow across an upper
radiator header like you would in a down-flow radiator. The radiator
inlet connection is down part way on the inlet tank and the flow goes
through the radiator core, most not seeing the light of day when
looking in the filler neck.
I just called another buddy about the fan system on this car - the
difference between trailer tow and non-trailer two configuration... he
worked on the fan system when he worked for Delco in the time frame.
He says that the JGC needs to have the engine driven fan operating at
highway speeds, that the ram air alone wasn't sufficient to keep the
coolant temperature controlled by the T' Stat.
The conventional (non trailer tow) system has an electric fan on the
engine side of the radiator inside the shroud (with enough power to
make the condenser work in air conditioning) and a engine driven fan
with a Delco fan clutch. This fan clutch was engineered for very low
drag - meaning that unless the bi-metal kicked it in the fan turned at
a low speed - you can stop the fan at idle with a pencil. Even kicked
in the fan clutch wasn't a real high torque clutch.
The trailer tow system was similar - an electric fan behind the
radiator and an engine driven Delco 1525 fan clutch with a higher
torque rating.
Your system is acting 'cooling limited' in that the coolant
temperature is a function of engine load. There are two possible
causes for this in the first breakdown.
- low coolant flow (as from an internally restricted radiator or a
collapsed coolant return hose
- low airflow with two possible causes
- blocked air path (bugs, mud, bent fins, airside corrosion
- inoperative fan
The blocked air path can be determined by looking at it - is the
condenser covered with dead bugs, do you have a bug screen, is it or
the radiator plugged up with dried mud (clay gets like concrete) or is
there a lot of white 'fuzz' corrosion on the louvers in the fins. If
it is bugs or mud you can clean it with a garden hose, don't use a
pressure washer or you'll fold the fins over and need to replace the
heat exchanger.
The inoperative fan can be checked this way - dig out the RTV holding
the leg of the bi-metal coil in position and lift it over the boss on
the clutch cover and rotate it counter-clockwise, let it rest against
the boss from the other side. This will leave the fan always engaged.
After driving the car to fully warm shut off the engine and see if
there is significant drag when you try to rotate the fan by hand. If
it spins pretty easily then the clutch is out of fluid and needs to be
replaced. If there is drag and the cooling problem goes away you need
to replace the clutch. If there is drag and the cooling problem
hasn't gone away then it is either problem with bugs / mud or internal
restriction on the coolant side of the radiator.
I would try the fan clutch bi-metal coil first - it doesn't cost
anything, its easy and it doesn't risk screwing anything up ...
reboot
---
avast! Antivirus: Outbound message clean.
Virus Database (VPS): 0703-0, 01/13/2007
Tested on: 1/14/2007 2:33:26 PM
avast! - copyright (c) 1988-2007 ALWIL Software.
http://www.avast.com
01-14-2007, 02:33 PM
#109
Guest
Posts: n/a
Re: Followup-- 2000 JGC V-8 still overheating
On Sun, 14 Jan 2007 12:36:16 -0500, "James" <jnipperxxx@nospamfdn.com>
wrote:
>Mike, it is the original water pump. SnoMan, yes, the fan does run at
>idle, with temp at 205.
>
>Yes, I do have tow package, and the coolant is full. It is up to the very
>top of the neck when I take the rad cap off. There is NO circulation of
>the coolant, and it is warm, but not really HOT, even when the gauge is at
>205.
>
>I think my next step is to take it to a rad shop and allow them to take the
>rad out and test it.
>
>Yes, I could have another "bad" (new) thermostat, but I don't know how
>many times I should try that. (I am not a mechanic, so I can't do that
>myself, so I have to leave it for a day when I have work done).
>
>Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
>it is a water pump or fan clutch problem. Could be another bad thermostat,
>OR a flow problem in the rad system.
>
>
> It just seems to me that if the car does fine at idle (can run all day
>at a redlight and not heat up), but heats some at 75mph and heats a LOT on
>long incline, no enough coolant is circulating around the engine. Again,
>this is just from a "lay" person.
>
>I do appreciate all of the comments though, thank you all!!
>
>
>--James--
>
I just made a call to a buddy in the OEM automotive thermostat
business who knows the T' Stat technical part pretty well, maybe he'll
join in.
Talking to him ... he recalls that the 4,7 has an Inlet Side T' Stat -
meaning that it controls the flow of coolant back into the engine from
the radiator. This contrasts with typical / conventional T' Stats
which control the flow leaving the engine.
Chrysler had some issues with the Front Cover in '99 and 2000 when the
4.7 was first introduced. The front cover mixes coolant circulating
from the block with coolant coming back from the radiator. This mixed
temperature is what the T' Stat sees and increases or decreases the
amount coming from the Radiator (there are lots of good reasons why an
inlet side T' Stat is a good idea). The problem that DCX had was that
this mixing volume in the front cover didn't quite work right and some
owners had problems from day one ... I believe the fix involved
replacing the front cover which isn't a simple job on this integrated
accessory drive motor.
With this inlet side T' Stat control the diagnostic logic isn't the
same as on conventional T' Stat engines - such as when a T' Stat is
installed backwards.
Regarding the coolant flow problem open cap at warm idle - if the
coolant is warm there is some flow taking place - simple physics. That
you cannot feel or see this flow means it is very low - and, since
this is a cross-flow radiator you don't see flow across an upper
radiator header like you would in a down-flow radiator. The radiator
inlet connection is down part way on the inlet tank and the flow goes
through the radiator core, most not seeing the light of day when
looking in the filler neck.
I just called another buddy about the fan system on this car - the
difference between trailer tow and non-trailer two configuration... he
worked on the fan system when he worked for Delco in the time frame.
He says that the JGC needs to have the engine driven fan operating at
highway speeds, that the ram air alone wasn't sufficient to keep the
coolant temperature controlled by the T' Stat.
The conventional (non trailer tow) system has an electric fan on the
engine side of the radiator inside the shroud (with enough power to
make the condenser work in air conditioning) and a engine driven fan
with a Delco fan clutch. This fan clutch was engineered for very low
drag - meaning that unless the bi-metal kicked it in the fan turned at
a low speed - you can stop the fan at idle with a pencil. Even kicked
in the fan clutch wasn't a real high torque clutch.
The trailer tow system was similar - an electric fan behind the
radiator and an engine driven Delco 1525 fan clutch with a higher
torque rating.
Your system is acting 'cooling limited' in that the coolant
temperature is a function of engine load. There are two possible
causes for this in the first breakdown.
- low coolant flow (as from an internally restricted radiator or a
collapsed coolant return hose
- low airflow with two possible causes
- blocked air path (bugs, mud, bent fins, airside corrosion
- inoperative fan
The blocked air path can be determined by looking at it - is the
condenser covered with dead bugs, do you have a bug screen, is it or
the radiator plugged up with dried mud (clay gets like concrete) or is
there a lot of white 'fuzz' corrosion on the louvers in the fins. If
it is bugs or mud you can clean it with a garden hose, don't use a
pressure washer or you'll fold the fins over and need to replace the
heat exchanger.
The inoperative fan can be checked this way - dig out the RTV holding
the leg of the bi-metal coil in position and lift it over the boss on
the clutch cover and rotate it counter-clockwise, let it rest against
the boss from the other side. This will leave the fan always engaged.
After driving the car to fully warm shut off the engine and see if
there is significant drag when you try to rotate the fan by hand. If
it spins pretty easily then the clutch is out of fluid and needs to be
replaced. If there is drag and the cooling problem goes away you need
to replace the clutch. If there is drag and the cooling problem
hasn't gone away then it is either problem with bugs / mud or internal
restriction on the coolant side of the radiator.
I would try the fan clutch bi-metal coil first - it doesn't cost
anything, its easy and it doesn't risk screwing anything up ...
reboot
---
avast! Antivirus: Outbound message clean.
Virus Database (VPS): 0703-0, 01/13/2007
Tested on: 1/14/2007 2:33:26 PM
avast! - copyright (c) 1988-2007 ALWIL Software.
http://www.avast.com
wrote:
>Mike, it is the original water pump. SnoMan, yes, the fan does run at
>idle, with temp at 205.
>
>Yes, I do have tow package, and the coolant is full. It is up to the very
>top of the neck when I take the rad cap off. There is NO circulation of
>the coolant, and it is warm, but not really HOT, even when the gauge is at
>205.
>
>I think my next step is to take it to a rad shop and allow them to take the
>rad out and test it.
>
>Yes, I could have another "bad" (new) thermostat, but I don't know how
>many times I should try that. (I am not a mechanic, so I can't do that
>myself, so I have to leave it for a day when I have work done).
>
>Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
>it is a water pump or fan clutch problem. Could be another bad thermostat,
>OR a flow problem in the rad system.
>
>
> It just seems to me that if the car does fine at idle (can run all day
>at a redlight and not heat up), but heats some at 75mph and heats a LOT on
>long incline, no enough coolant is circulating around the engine. Again,
>this is just from a "lay" person.
>
>I do appreciate all of the comments though, thank you all!!
>
>
>--James--
>
I just made a call to a buddy in the OEM automotive thermostat
business who knows the T' Stat technical part pretty well, maybe he'll
join in.
Talking to him ... he recalls that the 4,7 has an Inlet Side T' Stat -
meaning that it controls the flow of coolant back into the engine from
the radiator. This contrasts with typical / conventional T' Stats
which control the flow leaving the engine.
Chrysler had some issues with the Front Cover in '99 and 2000 when the
4.7 was first introduced. The front cover mixes coolant circulating
from the block with coolant coming back from the radiator. This mixed
temperature is what the T' Stat sees and increases or decreases the
amount coming from the Radiator (there are lots of good reasons why an
inlet side T' Stat is a good idea). The problem that DCX had was that
this mixing volume in the front cover didn't quite work right and some
owners had problems from day one ... I believe the fix involved
replacing the front cover which isn't a simple job on this integrated
accessory drive motor.
With this inlet side T' Stat control the diagnostic logic isn't the
same as on conventional T' Stat engines - such as when a T' Stat is
installed backwards.
Regarding the coolant flow problem open cap at warm idle - if the
coolant is warm there is some flow taking place - simple physics. That
you cannot feel or see this flow means it is very low - and, since
this is a cross-flow radiator you don't see flow across an upper
radiator header like you would in a down-flow radiator. The radiator
inlet connection is down part way on the inlet tank and the flow goes
through the radiator core, most not seeing the light of day when
looking in the filler neck.
I just called another buddy about the fan system on this car - the
difference between trailer tow and non-trailer two configuration... he
worked on the fan system when he worked for Delco in the time frame.
He says that the JGC needs to have the engine driven fan operating at
highway speeds, that the ram air alone wasn't sufficient to keep the
coolant temperature controlled by the T' Stat.
The conventional (non trailer tow) system has an electric fan on the
engine side of the radiator inside the shroud (with enough power to
make the condenser work in air conditioning) and a engine driven fan
with a Delco fan clutch. This fan clutch was engineered for very low
drag - meaning that unless the bi-metal kicked it in the fan turned at
a low speed - you can stop the fan at idle with a pencil. Even kicked
in the fan clutch wasn't a real high torque clutch.
The trailer tow system was similar - an electric fan behind the
radiator and an engine driven Delco 1525 fan clutch with a higher
torque rating.
Your system is acting 'cooling limited' in that the coolant
temperature is a function of engine load. There are two possible
causes for this in the first breakdown.
- low coolant flow (as from an internally restricted radiator or a
collapsed coolant return hose
- low airflow with two possible causes
- blocked air path (bugs, mud, bent fins, airside corrosion
- inoperative fan
The blocked air path can be determined by looking at it - is the
condenser covered with dead bugs, do you have a bug screen, is it or
the radiator plugged up with dried mud (clay gets like concrete) or is
there a lot of white 'fuzz' corrosion on the louvers in the fins. If
it is bugs or mud you can clean it with a garden hose, don't use a
pressure washer or you'll fold the fins over and need to replace the
heat exchanger.
The inoperative fan can be checked this way - dig out the RTV holding
the leg of the bi-metal coil in position and lift it over the boss on
the clutch cover and rotate it counter-clockwise, let it rest against
the boss from the other side. This will leave the fan always engaged.
After driving the car to fully warm shut off the engine and see if
there is significant drag when you try to rotate the fan by hand. If
it spins pretty easily then the clutch is out of fluid and needs to be
replaced. If there is drag and the cooling problem goes away you need
to replace the clutch. If there is drag and the cooling problem
hasn't gone away then it is either problem with bugs / mud or internal
restriction on the coolant side of the radiator.
I would try the fan clutch bi-metal coil first - it doesn't cost
anything, its easy and it doesn't risk screwing anything up ...
reboot
---
avast! Antivirus: Outbound message clean.
Virus Database (VPS): 0703-0, 01/13/2007
Tested on: 1/14/2007 2:33:26 PM
avast! - copyright (c) 1988-2007 ALWIL Software.
http://www.avast.com
01-14-2007, 02:58 PM
#110
Guest
Posts: n/a
Re: Followup-- 2000 JGC V-8 still overheating
James proclaimed:
> Mike, it is the original water pump. SnoMan, yes, the fan does run at
> idle, with temp at 205.
>
> Yes, I do have tow package, and the coolant is full. It is up to the very
> top of the neck when I take the rad cap off. There is NO circulation of
> the coolant, and it is warm, but not really HOT, even when the gauge is at
> 205.
Cheap cooking thermometer will get the real temperature, but all
symptoms so far say either your thermostat is not opening or your water
pump is not working overly well or there is a blockage.
>
> I think my next step is to take it to a rad shop and allow them to take the
> rad out and test it.
If you go to that expense, might as well replace it with an aftermarket,
but that sure seems like way too many dollars spent rather than
troubleshooting.
A *good* cooling shop would have already checked your water pump for
flow and your thermostat for opening and your system for blockages that
impede flow.
Or a very small head gasket problem that lets exhaust into the fluid but
only at higher engine speeds [not that probable from your symptoms so far].
>
> Yes, I could have another "bad" (new) thermostat, but I don't know how
> many times I should try that. (I am not a mechanic, so I can't do that
> myself, so I have to leave it for a day when I have work done).
As a diagnostic, remove the thermostat. Yes, your engine may warm up
slowly and fail emissions during warm up, but at least you've removed
the easy part of determining if the thermostat is bad as installed.
If you don't see flow with the thermostat removed, your water pump is
bad or you have a blockage.
You can test the thermostat while it is out by putting it in water and
slowly heating the water to see if the thermostat opens. Again a cheap
cooking thermometer works.
>
> Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
> it is a water pump or fan clutch problem. Could be another bad thermostat,
> OR a flow problem in the rad system.
It really isn't that difficult to remove possibilities, but it works
better if it is done scientifically rather than philosophically--which
isn't doing that good so far.
>
>
> It just seems to me that if the car does fine at idle (can run all day
> at a redlight and not heat up), but heats some at 75mph and heats a LOT on
> long incline, no enough coolant is circulating around the engine. Again,
> this is just from a "lay" person.
If you let it idle and it doesn't overheat, you should still have
coolant going thru the radiator. Your fan should also be cycling.
If your coolant isn't flowing [which is admittedly incompatible with
many of the symptoms proposed] the engine heats up...which may not be
obvious if the coolant cannot hit the temperature sensot. A second
means of measuring coolant temp is a good idea... the radiator coolant
should heat up but measure it, don't assume.
Oddball ignition can heat an engine at higher load as can a head gasket
leak, but both of those tend to have other symptoms and I'd hope your
PCU would throw a code on ignition retard.
Heating at 75 and on inclines usually mean someone has replace a major
part of the cooling system without quite knowing what they are doing.
>
> I do appreciate all of the comments though, thank you all!!
>
>
> --James--
>
>
> Mike, it is the original water pump. SnoMan, yes, the fan does run at
> idle, with temp at 205.
>
> Yes, I do have tow package, and the coolant is full. It is up to the very
> top of the neck when I take the rad cap off. There is NO circulation of
> the coolant, and it is warm, but not really HOT, even when the gauge is at
> 205.
Cheap cooking thermometer will get the real temperature, but all
symptoms so far say either your thermostat is not opening or your water
pump is not working overly well or there is a blockage.
>
> I think my next step is to take it to a rad shop and allow them to take the
> rad out and test it.
If you go to that expense, might as well replace it with an aftermarket,
but that sure seems like way too many dollars spent rather than
troubleshooting.
A *good* cooling shop would have already checked your water pump for
flow and your thermostat for opening and your system for blockages that
impede flow.
Or a very small head gasket problem that lets exhaust into the fluid but
only at higher engine speeds [not that probable from your symptoms so far].
>
> Yes, I could have another "bad" (new) thermostat, but I don't know how
> many times I should try that. (I am not a mechanic, so I can't do that
> myself, so I have to leave it for a day when I have work done).
As a diagnostic, remove the thermostat. Yes, your engine may warm up
slowly and fail emissions during warm up, but at least you've removed
the easy part of determining if the thermostat is bad as installed.
If you don't see flow with the thermostat removed, your water pump is
bad or you have a blockage.
You can test the thermostat while it is out by putting it in water and
slowly heating the water to see if the thermostat opens. Again a cheap
cooking thermometer works.
>
> Coming from the viewpoint only of a lay person (non-mechanic) I just doubt
> it is a water pump or fan clutch problem. Could be another bad thermostat,
> OR a flow problem in the rad system.
It really isn't that difficult to remove possibilities, but it works
better if it is done scientifically rather than philosophically--which
isn't doing that good so far.
>
>
> It just seems to me that if the car does fine at idle (can run all day
> at a redlight and not heat up), but heats some at 75mph and heats a LOT on
> long incline, no enough coolant is circulating around the engine. Again,
> this is just from a "lay" person.
If you let it idle and it doesn't overheat, you should still have
coolant going thru the radiator. Your fan should also be cycling.
If your coolant isn't flowing [which is admittedly incompatible with
many of the symptoms proposed] the engine heats up...which may not be
obvious if the coolant cannot hit the temperature sensot. A second
means of measuring coolant temp is a good idea... the radiator coolant
should heat up but measure it, don't assume.
Oddball ignition can heat an engine at higher load as can a head gasket
leak, but both of those tend to have other symptoms and I'd hope your
PCU would throw a code on ignition retard.
Heating at 75 and on inclines usually mean someone has replace a major
part of the cooling system without quite knowing what they are doing.
>
> I do appreciate all of the comments though, thank you all!!
>
>
> --James--
>
>