View Full Version : What is HOT for a blown head gasket

11-16-07, 02:08 PM
What is considered HOT in terms of temperature to suggest a blown head gasket?

Last week drove a 97 Deville with AC on and at highway speeds and also start stop and it showed a temp of 212 on the display. The outside air was only about 51 so I have no idea what the temp would be in 90 or 100 degree air which we generally have in the summer in MD.

My C5 Corvette with the LS1 engine ran at a max of 189 degrees under the same conditions. Was the Deville exhibiting overheating in this cold air environment.

What do you consider NORMAL for the temp in this weather?


11-16-07, 02:29 PM
Relax. 205-215 is normal operating temperature.

11-16-07, 02:30 PM
The fans don't come on until 224. So it depends on traffic flow.

11-16-07, 03:51 PM
The thermostat in that car begins to open at 188 and is fully open at 206. 212 is right where it should be. Summer or winter........but the temp will creep up to 220 +/- in downtown Baltimore in August, the fan(s) will go to High (A/C on) at 234, and the temp will come down. Boiling with 50/50 DEX-COOL is (264?) at 16 lb. (One or both fans always run in A/C or AUTO mode, so the temp swings are slower and less range)

11-16-07, 09:48 PM
My '97 (Digidash) ran 206 (summer) 213 (winter), consistently.

JN in CA
11-17-07, 12:09 AM
As Submariner says, the thermostat isn't fully open until 206. I never see less than 212, unless its winter and I have the heater going.