LT4 Overheating Question
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Instructor
Joined: Nov 2000
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my car had very similar problems. my car blew a head gasket at like 93k. i think the previous owner had a little too much fun with nitrous. but it had made a small crank in my radiator that wouldn't drip cause it was high enough on the radiatior the coolant would evaporate before hitting the ground. for quite a while i thought that i had another bad head gasket or something wrong cause i could smell the coolant and after blowing a radiator hose and replacing the waterpump (that also started leaking) i finally had enough pressure in the system to show a leak. some ideas to look into.
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Instructor
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A couple of questions; is the car overheating while you are idling only or all the time?
Interestingly enough, yesterday when I just let it sit and idle, it went up to 228, both fans kicked on, and the temps came back down. I didn't let it run for a long time after that, so I'm not sure how low they went.
If the car keeps cool while running; I would look at the fans. I had problems with both fans, more specifically the fan motors.
That's when it gets up in the 230s, but it doesn't stay there. It fluctuates up and down.
Also, make sure your front air dam is in good condition and that their is no junk in front of the radiator.
Checked that!
One last thing is to check that the fan shroud is in good condition. Most people won't experience this problem; but I had to cut my shroud when I put in a Be-Cool Radiator and accomodate the extra thickness of the radiator and my supercharger. I ended up going back to the stock radiator.
Anyway, good luck.
Glenn
Interestingly enough, yesterday when I just let it sit and idle, it went up to 228, both fans kicked on, and the temps came back down. I didn't let it run for a long time after that, so I'm not sure how low they went.
If the car keeps cool while running; I would look at the fans. I had problems with both fans, more specifically the fan motors.
That's when it gets up in the 230s, but it doesn't stay there. It fluctuates up and down.
Also, make sure your front air dam is in good condition and that their is no junk in front of the radiator.
Checked that!
One last thing is to check that the fan shroud is in good condition. Most people won't experience this problem; but I had to cut my shroud when I put in a Be-Cool Radiator and accomodate the extra thickness of the radiator and my supercharger. I ended up going back to the stock radiator.
Anyway, good luck.
Glenn
Burning Brakes
Joined: Oct 2004
Posts: 1,210
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From: fighter pilots make movies, bomber pilots make history
Use the Barrs tablets, same thing as the GM parts counter tablets.
Most all GM cars and ALL Corvette have this added at the FACTORY. It is part of the recommended procedure in the field service manual when a flush is performed.
Joe
Do the pressure test to look for leaks that can be corrected mechanically, tablets or liquids with suspended particles seal micro leaks.
Most all GM cars and ALL Corvette have this added at the FACTORY. It is part of the recommended procedure in the field service manual when a flush is performed.
Joe
Do the pressure test to look for leaks that can be corrected mechanically, tablets or liquids with suspended particles seal micro leaks.
Last edited by devildog; Oct 6, 2008 at 09:37 PM.
Thread Starter
Instructor
Joined: Nov 2000
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Turns out the radiator has a crack in it. I guess it was never big enough to notice until last night when it became real noticeable. I hope that's the only problem. I'll know after tomorrow.
Thanks to all who posted comments.
Thanks to all who posted comments.
Drifting
Joined: Sep 2003
Posts: 1,363
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From: 1994 LT1 Coupe 6-speed with FX3 & 2000 LS1 Vert 6-Speed with F45 Hunterdon County, NJ
Use the Barrs tablets, same thing as the GM parts counter tablets.
Most all GM cars and ALL Corvette have this added at the FACTORY. It is part of the recommended procedure in the field service manual when a flush is performed.
Joe
Do the pressure test to look for leaks that can be corrected mechanically, tablets or liquids with suspended particles seal micro leaks.
Most all GM cars and ALL Corvette have this added at the FACTORY. It is part of the recommended procedure in the field service manual when a flush is performed.
Joe
Do the pressure test to look for leaks that can be corrected mechanically, tablets or liquids with suspended particles seal micro leaks.
Burning Brakes
Joined: Oct 2004
Posts: 1,210
Likes: 1
From: fighter pilots make movies, bomber pilots make history
Joe
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Race Director
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From: D / FW
I will also add water wetter when I recharge w/antifreeze which I might add needs replaced every three years.
Burping is important as a little air can keep the liquid from flowing.
My Hot Rod 95 LT 4 has a new radator and never overheats.
These Aluminum Radiators need replaced as they stop working right when they get corroded with time.
No need for high dollar the HD stock is fine.
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Instructor
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Thread Starter
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Race Director
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Le Mans Master
Joined: Dec 2006
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From: H-Town Texas
The heads will probably need some machining anyway, so the porting will probably not add that much to the bill.
