Overheated to 250 degrees
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From: Woodstock, GA
Overheated to 250 degrees This recent cold snap caused an issue with my cooling system. It's been fine since the build, until a few days ago, 10 degrees outside, she overheated to 250 and acted like there was air in the system. There was also a small puddle of frozen coolant under the car. Cracked block, freeze plug?
Last edited by TA_Freak; Dec 27, 2022 at 08:24 AM.
Is there still coolant in the radiator? If so with a small puddle, I'd check for leaks from the hoses, return lines and around other parts of cooling system like water pump and radiator.
FWIW - that coolant line to and from the throttle body is sometimes a leak source that easy to forget to check. Folks seldom replace that line when doing hoses etc. Likewise for small return lines.
FWIW - that coolant line to and from the throttle body is sometimes a leak source that easy to forget to check. Folks seldom replace that line when doing hoses etc. Likewise for small return lines.
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From: Woodstock, GA
Is there still coolant in the radiator? If so with a small puddle, I'd check for leaks from the hoses, return lines and around other parts of cooling system like water pump and radiator.
FWIW - that coolant line to and from the throttle body is sometimes a leak source that easy to forget to check. Folks seldom replace that line when doing hoses etc. Likewise for small return lines.
FWIW - that coolant line to and from the throttle body is sometimes a leak source that easy to forget to check. Folks seldom replace that line when doing hoses etc. Likewise for small return lines.
Unless you are running something other than a 50/50 coolant, this shouldn't happen. I've driven my Firebird in -35 degree weather without issue.
Hopefully you just have something loose. Given your temperature and what sounds like a small leak that isn't holding pressure. I'd fill the system and rent a pressure tester. https://www.autozone.com/loan-a-tool...ressure-tester
If you manually pressurize the system with the engine off, hopefully the leak and issue should make itself evident to you.
Hopefully you just have something loose. Given your temperature and what sounds like a small leak that isn't holding pressure. I'd fill the system and rent a pressure tester. https://www.autozone.com/loan-a-tool...ressure-tester
If you manually pressurize the system with the engine off, hopefully the leak and issue should make itself evident to you.
The exact same thing happened to my H2 when it was -19. I'm pretty sure the water pump got stuck as I heard a chirp when I started it and it soon overheated just as you described. I also had a small puddle of coolant but no leak after that. My belt was very shiny as well. Im pretty sure my coolant was in good condition too. IDK never seen anything like it.
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From: Woodstock, GA
I don't honestly know what the mixture of coolant/water was. This build was a nightmare from day one. I wouldn't doubt if it was 10% coolant and 90% water. When I shut the car down at 250, i could hear all kinds of popping and clicking and sounds that were not very nice to hear. I filled it up with coolant today and took her for a ride and it didn't overheat or leak. I still have no confidence yet. Guess I'll drive my C6 to work tomorrow. 
Jamie, this is concerning because you stated in post #1 that there was frozen coolant under the car. Coolant with the proper 50/50 minimum won’t freeze. Sounds like mostly water to me.
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From: Schiller Park, ILL Member: #317
My first thought as well when I read the initial post. If the coolant is freezing at 10°F then it's pretty weak (mostly water), I think you should be good down to about -35°F with 50/50.
Also alarming that it was so low on coolant in the first place. Where did it all go if the puddle was small? Is it perhaps burning coolant?
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Go to the parts store and buy a coolant tester. It's a little turkey baster type device with floating ***** in it. It will tell you what your coolant percentage is, or at least to what temp it will protect to. But these observations above are correct - Coolant shouldn't freeze. I'd be draining and refilling ASAP.
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From: Woodstock, GA
My first thought as well when I read the initial post. If the coolant is freezing at 10°F then it's pretty weak (mostly water), I think you should be good down to about -35°F with 50/50.
Also alarming that it was so low on coolant in the first place. Where did it all go if the puddle was small? Is it perhaps burning coolant?
Go to the parts store and buy a coolant tester. It's a little turkey baster type device with floating ***** in it. It will tell you what your coolant percentage is, or at least to what temp it will protect to. But these observations above are correct - Coolant shouldn't freeze. I'd be draining and refilling ASAP.
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From: Woodstock, GA
If the weather had been even close to 18 degress, I'd have done that by now - but she sits for now. It;s been quite warm here. If that wasn't the case and it was colder, It would have been escalated in my priorities.
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From: Woodstock, GA
I drove her 80 miles without any issues. It wasn't that cold here in Atlanta so .....
I will say that I got used to the feel of my C6 and damn are those two different animals.
I will say that I got used to the feel of my C6 and damn are those two different animals.