Overheating ...
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Cruising
Joined: Jul 2019
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From: Decatur Georgia
Overheating ...
I have an 89 c4 I started overheating & replaced to date the thermostat water pump radiator head gasket ..got the heads milled ...& all the hoses are new ..I’m still over heating ...somebody help
Melting Slicks
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From: Longmont Co
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From: Indianapolis IN
Finalist 2020 C4 of the Year - Unmodified
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Basic question: Is the area between the AC condenser and the face of your radiator clean? (You didn't say if you removed the radiator during the engine work OR whether or not you have inspected and/or cleaned it) If you have not checked, remove your radiator shroud and look in there...you will be surprised how much debris gets sucked up from underneath stuck up against the face of your radiator. Being you're in Georgia, I would expect there to be a bazillion pine needles in there.
Team Owner
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From: PA
2022 C4 of the Year Finalist - Unmodified
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St. Jude Donor '08
Basic question: Is the area between the AC condenser and the face of your radiator clean? (You didn't say if you removed the radiator during the engine work OR whether or not you have inspected and/or cleaned it) If you have not checked, remove your radiator shroud and look in there...you will be surprised how much debris gets sucked up from underneath stuck up against the face of your radiator. Being you're in Georgia, I would expect there to be a bazillion pine needles in there.
X2. And, once you get it cleaned out initially, I recommend pulling that radiator every few years and cleaning it as part of routine maintenance. I do that when I flush and replace the coolant, every 3-5 years or so.
Thread Starter
Cruising
Joined: Jul 2019
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From: Decatur Georgia
Safety Car
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From: Indianapolis IN
Finalist 2020 C4 of the Year - Unmodified
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Thread Starter
Cruising
Joined: Jul 2019
Posts: 13
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From: Decatur Georgia
Safety Car
Joined: Mar 2003
Posts: 3,586
Likes: 504
From: Indianapolis IN
Finalist 2020 C4 of the Year - Unmodified
C4 of Year Finalist (stock) 2019
Here are a couple of more thoughts:
When you installed the intake gaskets do you remember which end the restricted side was placed? (Front or rear?) They should be installed rearwards. If you installed the gaskets as received with one end restricted and installed them wrong, that would cause an overheat issue.
Another potential issue could be trapped air in the system. That would definitely cause overheating. I always use a coolant vacuum fill tool when refilling the system. That eliminates ANY chance of air being caught in the system anywhere.
When I did this same job in my '87 and I got the intake install, I eliminated those restrictors and opened both ends up. Refilled using the vacuum tool, and my engine temps were textbook perfect under ALL driving conditions using the stock 195° thermostat.
When you installed the intake gaskets do you remember which end the restricted side was placed? (Front or rear?) They should be installed rearwards. If you installed the gaskets as received with one end restricted and installed them wrong, that would cause an overheat issue.
Another potential issue could be trapped air in the system. That would definitely cause overheating. I always use a coolant vacuum fill tool when refilling the system. That eliminates ANY chance of air being caught in the system anywhere.
When I did this same job in my '87 and I got the intake install, I eliminated those restrictors and opened both ends up. Refilled using the vacuum tool, and my engine temps were textbook perfect under ALL driving conditions using the stock 195° thermostat.
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From: Lacey WA RVN 68-69
NCM Sinkhole Donor
I agree that there could be air trapped in the system. Try raising the front of the car as high as you can. Remove the pressure cap and start the engine. Get the coolant temp up to around 180 degrees F. Raise the RPM to about 1100-1200. Once the thermostat opens, the coolant level should drop some, Add pre-mixed coolant until the level is just at the base of the filler neck. Replace the pressure cap and lower the car.
Take it for a ride and watch the coolant temp to see if that solved the problem. Also, are the lower air dam pieces attached and in good condition? The air dams help to direct cool air from the front of the car up to the radiator and A/C condensor.
Take it for a ride and watch the coolant temp to see if that solved the problem. Also, are the lower air dam pieces attached and in good condition? The air dams help to direct cool air from the front of the car up to the radiator and A/C condensor.