Weird spike in engine temp.
Thread Starter
Racer
Joined: Oct 2005
Posts: 427
Likes: 0
From: Cary Illinois
Weird spike in engine temp.
So I couldn't resist taking the vette out today here around Chicago. It was about 25 degrees but sunny so I headed into work. All went well until the return trip. I was cruising at about 45 mph when all of a sudden, the temp starts climbing from about 170 or so up to 230 degrees.
It stayed there for about three minutes and then slowly dropped back down to 170. I can't figure out what the heck could cause this. Being so cold, the outside air should have kept the temp down so this quick spike seems really unusual.
Any guesses where I should look?
Thanks,
Q
It stayed there for about three minutes and then slowly dropped back down to 170. I can't figure out what the heck could cause this. Being so cold, the outside air should have kept the temp down so this quick spike seems really unusual.
Any guesses where I should look?
Thanks,
Q
Racer
Joined: Jun 2006
Posts: 476
Likes: 0
From: Easton PA
if it happens more often there is a problem. likely causes could be leaky head gaskets. or it was a fluke thing, possible gauge malfunction.
you could pressure test your coolant system and check for leaks or possible internal leaks, watch to see if pressure goes down over period of time then you know coolant is escaping somewere
you could pressure test your coolant system and check for leaks or possible internal leaks, watch to see if pressure goes down over period of time then you know coolant is escaping somewere
Last edited by straub18045; Mar 7, 2008 at 08:34 PM.
Intermediate
Joined: Mar 2006
Posts: 35
Likes: 0
From: Dripping Springs TX
Assuming your coolant level and timing are correct and you dont have an air lock issue (everything was ok b-4 right?) I'd guess you have a t-stat issue. It may be holding the coolant in the engine to long.
It eventually must have opened and allowed coolant to flow otherwise you would have boiled over.
If you haven't replaced it in a while I'd do that first and put a 3/16" hole in the ring of the t-stat to allow some pressure relief.
Good Luck!
It eventually must have opened and allowed coolant to flow otherwise you would have boiled over.
If you haven't replaced it in a while I'd do that first and put a 3/16" hole in the ring of the t-stat to allow some pressure relief.
Good Luck!
Thread Starter
Racer
Joined: Oct 2005
Posts: 427
Likes: 0
From: Cary Illinois
The Thermostat hasn't been replaced by me so the age is really unknown. The antifreeze was replaced a year ago by me and everything has run like a top until this little blip. I checked everything I could see when I got home. No coolant leaks that I could see.
Either it was a fluke or I might just swap out the t-stat since it's a cheap part to swap out and see if that might have been the cause.
Thanks,
Q
Either it was a fluke or I might just swap out the t-stat since it's a cheap part to swap out and see if that might have been the cause.
Thanks,
Q
Intermediate
Joined: Mar 2006
Posts: 35
Likes: 0
From: Dripping Springs TX
The Thermostat hasn't been replaced by me so the age is really unknown. The antifreeze was replaced a year ago by me and everything has run like a top until this little blip. I checked everything I could see when I got home. No coolant leaks that I could see.
Either it was a fluke or I might just swap out the t-stat since it's a cheap part to swap out and see if that might have been the cause.
Thanks,
Q
Either it was a fluke or I might just swap out the t-stat since it's a cheap part to swap out and see if that might have been the cause.
Thanks,
Q
You probably already know but just in case this is what worked for me.
After t-stat change I filled system and started engine and let it get to running temp only(about190) and then shut it down and let it cool for 2 hours or more. Did that again up to 190 and shut it down and let it cool. Then topped of coolant and did that a third time.
It should now be bleed of any air you have in the cooling system.
Good luck!
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From: Orange Park Florida
Makes me feel like a kid again....I remember actually FREEZING the radiator solid, on a cold winter day with no anti freeze in it....I was about 19 or so....didn't check the freeze...duh....had 'other' hobbies....
engine of course hot hotter'n hell.....saw the gauge, stopped for a while to let it cool down, while I froze in the winter bitch wind....while sitting in the car....got home on the last run up....next day I poured hot water all over the rad enough to thaw and get some anit freeze in there, got VERY lucky and didn't loose the rad....
engine of course hot hotter'n hell.....saw the gauge, stopped for a while to let it cool down, while I froze in the winter bitch wind....while sitting in the car....got home on the last run up....next day I poured hot water all over the rad enough to thaw and get some anit freeze in there, got VERY lucky and didn't loose the rad....
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I wouild change the old thermostat 
Thread Starter
Racer
Joined: Oct 2005
Posts: 427
Likes: 0
From: Cary Illinois
I changed the theromstat this afternoon. I went with a NAPA premium unit - 180 degrees. I let it run for about 25 minutes and no spikes yet. I topped off the coolant and will try to go for a spin tomorrow if the weather permits.
Hopefully, this takes care of the issue.
Thanks for the advice, as always,
Q
Hopefully, this takes care of the issue.
Thanks for the advice, as always,
Q