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Sorry I am sure this has been asked a hundred times but I can't seem to pull anything up in the search. I am frustrated so please forgive me.
I have a 2003 c5z
It has been hotter than usual around here lately between 95-100 and my car has been running around 230f with the A/C on in traffic. It will run cooler if I turn the air off but still around 210f.
The hottest it got was 245 I then turned on the heater to cool it down. That worked.
So I just took the car in and had the thermostat changed to a 160f
And the fans adjusted to kick on at the cooler temp. They also put in fresh coolant. On the way home it was 95 out and the car still heated up to 235 this was on the freeway at 55mph. The freeway I was driving is a pretty steep grade for miles maybe a 16% if that helps to know.
Oh by the way my car has a Dewitt's aluminum radiator in it with the Dewitt's alloy shroud and dual Spall fans.
Do you guys have any suggestions?
I really would like to cruise around on hot days and enjoy my Vette and use my A/C.
I guess the next question is how hot is too hot for these cars.
Thanks for your help in advance. I hope to get this figured out.
Your original post says the temps were 230 to 245 BEFORE you touched the coolant. While it is possible that air may have gotten into the system when the work was done, It may not have,
Two ways to "burp the system":
Factory Service manual says this:
Start w/ a cold engine
Remove rad. cap
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Start engine
Idle for 1 minute
Install cap
Cycle RPM from idle to 3000 until coolant reaches 210F
Shut off engine
Remove cap
Top off
Often need to repeat this procedure to get all the air out.
2020 Corvette of the Year Finalist (performance mods)
C5 of Year Winner (performance mods) 2019
is your ac condenser clogged with dirt, rocks, trash, etc?... it's right in front of your radiator and if it gets clogged it will block airflow past the radiator... you might check the radiator (and intercooler if you have one) also to make sure it doesn't have any debris in it... I have a centri blower on mine with a dewitts radiator, spal fans, and 180 thermostat and it stays under 200 in the tx heat under normal driving and maybe up to 205-210 after some back to back hard runs so there is definitely some room for improvement in your situation
Just to be sure, turn on your a/c with coolant at operating temp, and see if both your electric fans are running. The fact that it cools down when your turn off the a/c sounds like possibly you have a blown fuse on one of your fans. They're 30 amp and in the engine fuse compartment. Just quickly check to be sure they are running all the time when you turn on the a/c. The temp must be over 185 for them to be forced on with the a/c.
Last edited by 65GGvert; Jul 17, 2014 at 11:57 AM.
I think I found the issue, a friend of mine has a chemical block check test kit. You put this fluid in it that is blue you then place it in your coolant tank. If the fluid turns yellow there is exhaust gas present. Mine didn't turn yellow right away but after about 10-15 minutes it turned green.
So I believe it is seeping exhaust gas into the coolant and causing my heating condition. This is at idle. I imagine it would be worse under boost. Unfortunately It's gotta be the head gaskets. Come to think of it all this started happening after the last dyno pull so it likely popped then.
I think I found the issue, a friend of mine has a chemical block check test kit. You put this fluid in it that is blue you then place it in your coolant tank. If the fluid turns yellow there is exhaust gas present. Mine didn't turn yellow right away but after about 10-15 minutes it turned green.
So I believe it is seeping exhaust gas into the coolant and causing my heating condition. This is at idle. I imagine it would be worse under boost. Unfortunately It's gotta be the head gaskets. Come to think of it all this started happening after the last dyno pull so it likely popped then.
I am bummed. This has to be expensive to repair.
If you were leaking exhaust gasses I would expect temps to be much higher than 245. The car is hot but not overheated. Green is not yellow so i would look elsewhere. Yes, replacing head gaskets can be very expensive.
My A&A Supercharged engine has been running 230-240 on hot days so I'm going to try out this larger capacity aftermarket radiator which is not too expensive at 249.00 plus shipping.
I had a leak down test done and there is no head gasket issue!!!
I also bought fresh fluid for my buddies tester and it passed that test as-well.
I did figure out the heat issue too!
There was 2 pounds of crap stuck in-between the condenser and radiator.
I was able to get it all cleaned out and now i am running 180 on the freeway with the a/c on an around 200 in town with a/c on. I am so happy this is resolved.
From: Reno is so close to Hell you can see Sparks , State Of Confusion
St. Jude Donor '12-'13-'14
First thing I would look at is cleaning the radiator, These are a bottom feeder and collect a lot of trash that sticks in the condenser and the radiator, I bought a kit to clean mine and my temps dropped 25-30 degrees.
Best 24 bucks spent.
Mr.Bill
First thing I would look at is cleaning the radiator, These are a bottom feeder and collect a lot of trash that sticks in the condenser and the radiator, I bought a kit to clean mine and my temps dropped 25-30 degrees.
Best 24 bucks spent.
Mr.Bill