1988 Corvette overheats ?
Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
Likes: 23
From: mesa az
1988 Corvette overheats ?
I have after lots of attempts managed to get the coolant level light to stay off. Only to come on again after long freeway driving. I have ZERO leaks. Never fluid underneath my car. Its pressure is perfect. What I have noticed is that my reserve never seems to suck back into the radiator ? Why is this ? I am stumped.
Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
Likes: 23
From: mesa az
No my motor is just fine. I run it on the freeway with average speeds of 75mph. No issues oil temp is 210-230. No funny smoke ! I am puzzeled by the fact that my water overflow tank never gets sucked back into the radiator ?
Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
Likes: 23
From: mesa az
I wait for the thermostat to open. The cap has been lose. The fan kicks on and the level drops a little bit. I then grab the throttle on top of the motor and rev it a bit and stay consistent waiting and adding fluid as needed. This method is a real pain in the *** but the only way to avoid air in the system. Is this what you mean ? I am simply amazed that despite this at times the light will come on again after some driving time. I am ready to buy a new fan as the factory one doesnt seem to be the best. Can you please recommend a fan to buy ? I want to thank you for taking the time to offer your advice. I also considered a small piece of electrically tape to cover the light. Sorta like sticking your head in the sand which wont solve a thing so I continue the battle. Temp usually runs 195 on the freeway and 210-235 in traffic.
Last edited by C4in mesa; Feb 11, 2012 at 05:43 AM.
Team Owner
Joined: Dec 2000
Posts: 90,675
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From: SE NY
Cruise-In II Veteran
Sounds like you are "burping" it properly.
If level in the radiator keeps going down but level in the resevoir is not going up then there is a coolant leak...somewhere.
If resevoir goes up but won't flow back into the radiator when cold, there is an air leak or a clog in the resevoir bottom or return hose.
If level in the radiator keeps going down but level in the resevoir is not going up then there is a coolant leak...somewhere.
If resevoir goes up but won't flow back into the radiator when cold, there is an air leak or a clog in the resevoir bottom or return hose.
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From: Macedon (near Rochester) NY
Those are normal temps with my 88. I also have the coolant level light going on after about half an hour of driving, but the level in the radiator and the level in the reservoir are always normal, so maybe the 88s just have sensors that go bad?
Thread Starter
Drifting
Joined: Dec 2011
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From: mesa az
My 1988 C4 ALWAYS has the coolant light coming on and off. I changed the radiator, all the hoses and still comes on and off. I do the proper burp but it is leaking somewhere ? I am going to pull all the plugs Saturday and do a compression test as well as a pressure test on the coolant system. I have been thinking it is leaking into my engine but no sign from the dip stick (levels remain the same and no change in the oil's appearance) My mechanic says it could be leaking in many spots due to the cars age and may not show up in the oil. I come to a stop and it goes up to 240+ degrees. If I am driving with no A/C it stays around 225. It is over 105 degrees here right now. Wish me luck in finding and solving this issue as it has plagued me since I bought this car. I have yet to pull the plugs and compression test. The coolant system pressure check was normal when I had a obvious leak in the radiator seam ! It was replaced along with all the hoses. I am going to yank the hoses off my reservoir tank because it never drains back into the radiator. I will look for a air leak. Any benefits if I bypass the throttle body ? And any tips for looking for an air leak that would affect the reservoir not draining back into the radiator ?
Burning Brakes
Joined: Aug 2001
Posts: 1,146
Likes: 9
From: Troy Ohio
I couldnt solve my 88 overheating problem either. Dewitts Radiator and a Stewart waterpump. Solved my overheating problem and runs a little too cool in cooler weather!!! But at least its not overheating anymore!!!!
Burning Brakes
Joined: Aug 2001
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From: Troy Ohio
Thread Starter
Drifting
Joined: Dec 2011
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From: mesa az
My coolant leak was through the intake manifold gasket. I checked the pressure on the radiator it was fine. All cylinders checked 165-180. I had water in the oil. Nothing noticeable out of the exhaust ? Yet after 10-15 miles the coolant light came on. Hard to believe that much water was leaking into the motor. [IMG][IMG]1988 C4 replacing intake mainfold gasket[/IMG][/IMG]
Drifting
Joined: Feb 2008
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From: NE Ohio
2024 C4 of the Year Finalist - Unmodified
I had same problem. Read the factory manual. It said that it was possible that condition could happen and may take 2 to 3 days to work air out of system. Drive and let set overnight 3 days and it should correct itself. I burped the system closed it up. Day one light came on quickly ( as soon as thermostat opened ). Day two it came on only at highway speeds 60 to 70. Day three and to now no low coolant light. I do have a new cap. Not sure the old one was bad.
Thread Starter
Drifting
Joined: Dec 2011
Posts: 1,439
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From: mesa az
You replaced the intake manifold gasket ? How much money did you spend on the job ? Did you replace the EGR since you had the thing exposed ? I did and I replaced the EGR temp sensor $60. the EGR A/C Delco $51, new gasket set $37, sealant $8, paint for the valve covers they looked like crap, PVC valve $3 hose $2, 5 quarts synthetic oil (had water) $30, new K&N oil filter $15, $2 6 bolts since they broke off or stripped getting them off. $300 in labor for the whole job. I am going to look for a buyer or trade it in to a dealership since it does have 194,000 miles. I am afraid the motor will just fail all together very soon. Gut feeling ? Not sure ? If it does I found a shop in Tucson to rebuild the motor with an improved cam out the door in a week for $2,300.