LT4 overheating
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Joined: Jun 2003
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From: Sasebo Kyushu
LT4 overheating
I am a new owner of a 96 corvette regular production LT4. It is getting up to 210 degrees and I'm not sure how to fix it. The coolant level is fine, and I'm pretty sure the fans work. If anyone has any suggestions please help. I have a knowledge of cars and have worked on them for 6 years. Thank you.
Melting Slicks
Joined: Dec 2001
Posts: 2,765
Likes: 0
From: Dana Point Ca
Re: LT4 overheating (TxAgNavyVette96)
These cars just run hot. I just put a Meziere HD waterpump AND a 180 degree thermostat and my LT4 still runs hot. The only way to correct it is to reprogram the ecm to have the fans kick on sooner. This can be done with the handheld units.
Good luck :flag
Good luck :flag
Le Mans Master
Joined: Jun 2002
Posts: 6,097
Likes: 2
From: Cincinnati Oh
Re: LT4 overheating (TxAgNavyVette96)
The factory setting for the fans is at ~230. So sitting in traffic you can easily see those temps. Pull the radiator and clean it, flush the coolant, program the computer to turn the fans on sooner, and install a 160* thermostat and she'll run alot cooler. (The HD electric water pump is great too).
In the meantime you can install a fan switch or turn on the a/c which also turns on the fans.
Enjoy the LT4 and Welcome!
In the meantime you can install a fan switch or turn on the a/c which also turns on the fans.
Enjoy the LT4 and Welcome!
Melting Slicks
Joined: May 2001
Posts: 2,143
Likes: 7
From: San Diego CA
Re: LT4 overheating (TxAgNavyVette96)
Welcome to the world of LTx engines.
These things just designed to run hot. Don't be surprised if you see temps to 230-240 range, that's just normal. I've pushed mine to 260 many times (going up the mountains in 90+ ambient temps).
If you find yourself in stop and go traffic with the temps climbing leave the A/C on. The fans are controlled by the A/C condensor pressure when the A/C is on. With the A/C off, the fans cycle between ~228 and ~215 (LT4 may be a bit different as the fans have low/high speed operation as opposed to a primary/secondary fan).
I talked to Doug Rippie once about racing temps. He said 260s were pretty normal. As long as the coolant doesn't boil, it will be OK.
I think a 50/50 mix of anti-freeze/water at 15lbs pressure boils at something like 270.
If you notice the temps creeping up (after being sure you have the proper coolant level) . Check the radiator plenum area for large debris, i.e. plastic grocery bags, leaves, etc. The design of the C4 makes it a wonderful street vacuum cleaner.
If the temps are still creeping, the next thing to do is to pull the radiator and clean it out. There's a good TECH TIP on pulling and cleaning the radiator.
BTW: you picked a great car :cheers:
[Modified by John Row, 9:00 AM 6/30/2003]
These things just designed to run hot. Don't be surprised if you see temps to 230-240 range, that's just normal. I've pushed mine to 260 many times (going up the mountains in 90+ ambient temps).
If you find yourself in stop and go traffic with the temps climbing leave the A/C on. The fans are controlled by the A/C condensor pressure when the A/C is on. With the A/C off, the fans cycle between ~228 and ~215 (LT4 may be a bit different as the fans have low/high speed operation as opposed to a primary/secondary fan).
I talked to Doug Rippie once about racing temps. He said 260s were pretty normal. As long as the coolant doesn't boil, it will be OK.
I think a 50/50 mix of anti-freeze/water at 15lbs pressure boils at something like 270.
If you notice the temps creeping up (after being sure you have the proper coolant level) . Check the radiator plenum area for large debris, i.e. plastic grocery bags, leaves, etc. The design of the C4 makes it a wonderful street vacuum cleaner.
If the temps are still creeping, the next thing to do is to pull the radiator and clean it out. There's a good TECH TIP on pulling and cleaning the radiator.
BTW: you picked a great car :cheers:
[Modified by John Row, 9:00 AM 6/30/2003]
