How can I fix my overheating problem?


Asked by Sep 21, 2014 at 11:57 PM about the 1986 Chevrolet Corvette Coupe

Question type: Maintenance & Repair

Hello, I have a 1986 corvette that keeps heating up and I have tried everything. I've literally changed the thermostat, radiator, hoses, water pump, checked for timing, fuel injectors, and practically cleaned out everything that has to deal with the cooling system. I've also searched for any leaks and found nothing, took my C4 to mechanics and asked them to check what the problem was and every single one of them told me that nothing was wrong. I am asking you guys to help me please, ever since I've bought this car its been heating up and has been for almost a year. Can you guys help me solve this big problem?

7 Answers


If there are no leak,s,and no fluid lost,and car has no skip,you may want to check the fan clutch,may be bad ,not turning properly will do this.

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Ohhh I also forgot to mention that I've changed the fan as well and replaced it with a high performance 2360 cfm fan, which worked well when I had barely installed it but within 2 days the temperature started rising again. With the stock fan the temperature would exceed it's boiling point which is 300° , But with the upgraded fan it still boils over reaching 265-270°

1 out of 1 people think this is helpful.

Good old corvettes ... Has the motor been rebuilt ? Bored cyl.cause more heat transfer from cyl. To the water jacket.. Vets are always having this problem .. Big motors in small spaces.. You can try / radiator with a bigger core or a universal electric fan to assist clutch fan... If you have the space to mount it.. Good luck..


Clearly system heat is not being released. Are you certain there is no air pocket, and coolant is flowing freely? Hoses firm & under pressure? Even new radiators, thermostats and water pumps can have issues. Is it possible someone used a stop leak product at some time? This can clog engine coolant galleries, or restrict them, a flush or fiber optic inspection may reveal blockage. Recheck your new water pump that it is directing coolant properly, GM has several that will fit but pump in different directions. My bet is something is impeding coolant flow, that high performance fan alone you installed would remove enough heat. Try these forums also: also your local corvette club if you don't belong already. cheers.

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John Carson

Have someone with a hear sensor gun shoot your engine and find where the hot spots are. If they are in the heads, the water flow jackets may be plugged. I had this problem several years ago and after tearing the heads off, discovered the gaskets were a universal style made for several motors. Some of my water jackets were blocked by the gasket. The gaskets had perforations to open the water jacked holes if there were ones that were blocked by the "universal" gaskets. If you upped the horse power of the engine, remember, there are more houses under the hood and more HP equates to more heat. Make sure the heat gauge is working correctly and the heat sensor is good. If you are using the A/C in town and it heats up, pop the hood release and see if the additional release of air around the hood helps increase the air flow and reduce the trapped heat. Just don't slam on the brakes as the hood may open. Normally the driving will produce enough air down draft to keep the hood in place. Do you have a proper radiator cap? That has been an issue in the past for people also. Little things can create big problems. Also is the radiator fluid the proper mix? Do check the direction of the water pump as suggested above. Morons in parts stores sometimes don't know there are two different directional flow pumps and don't check or ask what you need.

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Did you flush the system , and add new water and antifreeze??

1 out of 1 people think this is helpful.

Jump the relay connection to the fuse box. Fan will run when you start the car. Such a simple and great way to cool em down.

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