Engine Overheating
Thread Starter
4th Gear
Joined: Jul 2020
Posts: 4
Likes: 0
Engine Overheating
Hello,
I am newly made owner of a 1979 Corvette. There are hardly any issues except for the engine running hot. The car stays at a good temperature while idling, but once it's driven for 40ish minutes the heat quickly goes up to 230°-250°. I just replaced the stat in it to see if I could get lucky with a quick and cheap fix, but no dice. It still runs hot. I was wondering if anyone had any suggestions. Thanks!
I am newly made owner of a 1979 Corvette. There are hardly any issues except for the engine running hot. The car stays at a good temperature while idling, but once it's driven for 40ish minutes the heat quickly goes up to 230°-250°. I just replaced the stat in it to see if I could get lucky with a quick and cheap fix, but no dice. It still runs hot. I was wondering if anyone had any suggestions. Thanks!
Drifting
Joined: Mar 2009
Posts: 1,461
Likes: 361
From: Monson MA
First thing you want to do is get a laser temp gun. They like 30.00. I thought mine was but the gauge is off. Also does your car have a clutch on the fan. I'm just not familiar with your year. If so, open the hood with the car running. Watch the fan and turn the car off. The fan should stop within 2 rotations. If it free spins, that is a issue and you need to replace the clutch on the fan.
Race Director
Joined: Nov 2006
Posts: 13,227
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From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
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Cruise-In VIII Veteran
If you do a Google search on overheating Corvette, you will find a TON of threads on overheating.
as stated above, check the lower Radiator hose. the original one had a spring inside of it to keep it from getting sucked in. Most replacements don't have the spring. Is your front spoiler in place? Very important. Is your ignition timing correct for your engine combination? Not necessarily the factory timing. Are ALL the seals in place around the Radiator? Very important as well.
fan? Fan clutch? Condition of the Radiator? These things I list last as you say it keeps cool while idleing.
as stated above, check the lower Radiator hose. the original one had a spring inside of it to keep it from getting sucked in. Most replacements don't have the spring. Is your front spoiler in place? Very important. Is your ignition timing correct for your engine combination? Not necessarily the factory timing. Are ALL the seals in place around the Radiator? Very important as well.
fan? Fan clutch? Condition of the Radiator? These things I list last as you say it keeps cool while idleing.
Last edited by 4-vettes; Jul 15, 2020 at 06:36 AM.
Is my vette stock?? HAHA
Joined: Oct 2015
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From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
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is it high all the time hgihway driving city and stop and go?
If its all the time then it could be your lower hose collapsing. It should have a spring in it. Just give it a squeeze and you can tell if theres a spring in there. Your thermostat could be stuck as well. You can run no thermostat and see if the problem persists
IF its while driving at speed then
If its all the time then it could be your lower hose collapsing. It should have a spring in it. Just give it a squeeze and you can tell if theres a spring in there. Your thermostat could be stuck as well. You can run no thermostat and see if the problem persists
IF its while driving at speed then
- you need to make sure your front air dam is in place to deflect air into the space in front of the radiator
- you need to check all the seals around the radiator support
- all the seals on the radiator
- may need to flush the raidator or take it to a shop and have it cleaned thoroughly. Theycan plug. what color is your fluid. isit a clear green or is it stained brown?
- your fan clutch. It should spin free when its cold
- make sure the fan shroud is on and full
- If your car has an A/T make sure your transmission is shifting into the higher gears and your not running in first or second all the time
Thread Starter
4th Gear
Joined: Jul 2020
Posts: 4
Likes: 0
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
Likes: 9,348
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
It could. The fan is supposed to pull air through the radiator and if theres a hole like that it will pull from the easiest path which is to that side
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Melting Slicks
Joined: Apr 2001
Posts: 3,399
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From: Olmsted Falls, Ohio
Is it missing the seals around the top of the radiator? Sure is a big gap there.
If so, all that air is going over the radiator and not through it.
If so, all that air is going over the radiator and not through it.
Last edited by KenSny; Jul 15, 2020 at 01:20 PM.
