Over heat Help
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Joined: Dec 2003
Posts: 63
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From: Roosevelt NY
Over heat Help
have a 99 that recently indicated low coolant on the dash. When I added the dexcool and water the vett is now running hot and still showing low coolant.
Ive tried filling it with the engine running and with it off. It has even boiled out when I try to fill it while it was running.
Has anyone had this problem? and what is the fix.
Help
Ive tried filling it with the engine running and with it off. It has even boiled out when I try to fill it while it was running.
Has anyone had this problem? and what is the fix.
Help
Thread Starter
Advanced
Joined: Dec 2003
Posts: 63
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From: Roosevelt NY
Yes I have made sure there was nothing in front of the radiator.
After worm up it reads 217 - 221 for a few. Then it start to rise up as high as 247 -250. could this be a therestat problem?
After worm up it reads 217 - 221 for a few. Then it start to rise up as high as 247 -250. could this be a therestat problem?
Le Mans Master
Joined: Apr 2000
Posts: 6,760
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From: Southeast Nebraska
Cruise-In II Veteran
Are the fans coming on? If the fans aren't running, you can overheat and boil over some fluid. The car won't overheat with normal high speed driving, but stop-n-go will cause overheating.
Racer
Joined: Jan 2004
Posts: 255
Likes: 41
From: Lake Charles LA
heating problem
It sounds like the thermostat is not opening fully. My '97 was doing the same thing, and I installed a Hypertech 160 'stat, and my coolant temp now averages around 178 while cruising, and no hotter than 206 in traffic, idling, with outside temperature abount 96. I also drained the old Dex cool and replaced it with fresh. It is a very easy job.
Team Owner
Joined: Mar 1999
Posts: 28,753
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From: San Jose/Bear Valley CA
CA Events Coordinator
Is the coolant circulating? Are the fans coming on at all? You may need a new radiator cap, thermostat or have the fans checked. Dont ever try to open the rad cap when the car is 250 deg... that is way too hot!!
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Safety Car
Joined: Sep 2001
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From: Wilmington NC
Originally Posted by Crow Hunter
It sounds like the thermostat is not opening fully. My '97 was doing the same thing, and I installed a Hypertech 160 'stat, and my coolant temp now averages around 178 while cruising, and no hotter than 206 in traffic, idling, with outside temperature abount 96. I also drained the old Dex cool and replaced it with fresh. It is a very easy job.
This is a bit of a thread diversion, but do you really coolant temperatures that low when cruising? What does that leave your oil temperature at?
Le Mans Master
Joined: Apr 2000
Posts: 6,760
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From: Southeast Nebraska
Cruise-In II Veteran
I would be easy to see if the thermostat is opening, just feel the radiator return hose (of course don't burn yourself). If it is hot (and the radiator) the thermostat is opening. You may have a bad seal on the radiator fill cap. There is a TSB for fixing this, so it is a known problem with GM. The TSB calls for polishing the radiator fill cap seat area with 400 grit wet/dry, backed by a wooden dowl or stick. Replace the radiator cap with a new one. If the coolant system isn't pressurizing, it will boil oved and then overheat after the coolant is puked out.