Thermostat question / coolant temp question...
Thread Starter
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Thermostat question / coolant temp question...
After I got my carb back from the shop (they fixed a thread that I messed up) - I noticed that the car would run hotter than usual at idle... However - when driving on the highway the temp would get back to normal.. It used to be the opposite.. Usually the car was running cooler at idle and hotter at high speeds... I only use electric fans and therefore don't get so much better cooling on the highway... Now I'm thinking that maybe the carb shop accidently de-adjusted the idle mixture and I'm running a too lean idle mixture... Is this possible or could it be a problem with the thermostat? I'm planning on changing the thermostat anyway tomorrow to see if it solves the problem...but I still wonder if the hotter temp at idle could be caused by a too lean idle mixture?
:cheers:
Olivier
[Modified by GrandSportC3, 8:39 PM 12/22/2002]
:cheers:
Olivier
[Modified by GrandSportC3, 8:39 PM 12/22/2002]
Thread Starter
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Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Re: Thermostat question / coolant temp question... (wombvette)
The engine would eperience idle problems before you could get it lean enough to affect the temp at idle very much.
:cheers:
Olivier
Burning Brakes
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From: Ajax Ontario
Re: Thermostat question / coolant temp question... (GrandSportC3)
I dunno.....seems odd that your thermostat would act up at exactly the same time somebody was working on an unrelated component. Was timing adjusted? I bet something the mechanic did (carb/timing) is causing your problem. But, yes, it could be just a coincidence. Good luck! :cheers:
Thread Starter
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Re: Thermostat question / coolant temp question... (68shark)
I dunno.....seems odd that your thermostat would act up at exactly the same time somebody was working on an unrelated component. Was timing adjusted? I bet something the mechanic did (carb/timing) is causing your problem. But, yes, it could be just a coincidence. Good luck! :cheers:
Does anybody know in what direction I have to turn the idle mixture screws to get a richer mixture???
:cheers:
Olivier
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Re: Thermostat question / coolant temp question... (killain)
Sounds like the thermostat is sticking a bit!
:cheers:
Olivier
Safety Car
Joined: Dec 1999
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From: Roxbury NJ
Re: Thermostat question / coolant temp question... (GrandSportC3)
I dunno.....seems odd that your thermostat would act up at exactly the same time somebody was working on an unrelated component. Was timing adjusted? I bet something the mechanic did (carb/timing) is causing your problem. But, yes, it could be just a coincidence. Good luck! :cheers:
I haven't changed the timing since Lars set it to 37 degrees for me... The only thing that I changed was the jetting on the carb.(4 sizes largers jets 82 instead of 78).. The carb shop only had the carb (and not the car) and only repaired one thread... When I put the carb back on, the idle was at 2000 RPM.. I adjusted the idle back to around 1000 RPM... Since then - the engine is getting much hotter than usual at idle... The engine also warms up too quickly at slow speeds.. It used to take 10 minutes to warm up to 180 degrees... Now the temp hits 180 in 2 - 3 minutes... and the outside temp was colder than before... Anyway - I will change the thermostat tonite and check the idle mixture...
Does anybody know in what direction I have to turn the idle mixture screws to get a richer mixture???
:cheers:
Olivier
I haven't changed the timing since Lars set it to 37 degrees for me... The only thing that I changed was the jetting on the carb.(4 sizes largers jets 82 instead of 78).. The carb shop only had the carb (and not the car) and only repaired one thread... When I put the carb back on, the idle was at 2000 RPM.. I adjusted the idle back to around 1000 RPM... Since then - the engine is getting much hotter than usual at idle... The engine also warms up too quickly at slow speeds.. It used to take 10 minutes to warm up to 180 degrees... Now the temp hits 180 in 2 - 3 minutes... and the outside temp was colder than before... Anyway - I will change the thermostat tonite and check the idle mixture...
Does anybody know in what direction I have to turn the idle mixture screws to get a richer mixture???
:cheers:
Olivier
1. A bad t-stat cannot make the car warm up "too fast". A good thermostat will stay closed until the coolant reaches the specified temperature, then open. A bad thermostat may never close, and that would cause a longer than normal warm up. It can also stick closed, and cause overheating.
2. To richen the idle mixture, unscrew the adjusters. You did check how many turns out (from bottomed) they were before you sent the carb in, didn't you? ;)
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Burning Brakes
Joined: Jun 2002
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From: Norcross GA
Re: Thermostat question / coolant temp question... (GrandSportC3)
Any chance the sensors, wires, etc associated with the electric fan got jiggled loose or affected? No fan at idle equals no air flow and a hotter car. No fan at freeway speed means no fan blocking the flow, better air flow and cooler car.
Bob
Bob
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Re: Thermostat question / coolant temp question... (Flareside)
A few things:
1. A bad t-stat cannot make the car warm up "too fast". A good thermostat will stay closed until the coolant reaches the specified temperature, then open. A bad thermostat may never close, and that would cause a longer than normal warm up. It can also stick closed, and cause overheating.
2. To richen the idle mixture, unscrew the adjusters. You did check how many turns out (from bottomed) they were before you sent the carb in, didn't you? ;)
1. A bad t-stat cannot make the car warm up "too fast". A good thermostat will stay closed until the coolant reaches the specified temperature, then open. A bad thermostat may never close, and that would cause a longer than normal warm up. It can also stick closed, and cause overheating.
2. To richen the idle mixture, unscrew the adjusters. You did check how many turns out (from bottomed) they were before you sent the carb in, didn't you? ;)
:cheers:
Olivier
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Re: Thermostat question / coolant temp question... (Bobchad)
Any chance the sensors, wires, etc associated with the electric fan got jiggled loose or affected? No fan at idle equals no air flow and a hotter car. No fan at freeway speed means no fan blocking the flow, better air flow and cooler car.
Bob
Bob
:cheers:
Olivier
Thread Starter
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Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Re: Thermostat question / coolant temp question... (GrandSportC3)
I found the reason why my car was running too hot...
The hose from the breather to the vacuum port on the carb was disconnected... causing air flow through the vacuum port making the mixture way too lean...
I actually raced with the vacuum leak :eek: :eek: . I must have run way too lean.. I hope that I didn't do any damage to the engine doing that...
:cheers:
Olivier
The hose from the breather to the vacuum port on the carb was disconnected... causing air flow through the vacuum port making the mixture way too lean...
I actually raced with the vacuum leak :eek: :eek: . I must have run way too lean.. I hope that I didn't do any damage to the engine doing that...
:cheers:
Olivier