Hi I have a 2002 SL1 one owner just under 100k, and the coolant has started to boil over. The coolant system is new (except for the waterpump), so the suspect is the head gasket. No sign of water in the oil yet. Am wondering whether this may likely mean additional work on the head, such as a skim; and whether anyone can recommend someone to do the work in the NY area. Many thanks

 

Are you saying radiator, all coolant lines and thermostat and ects are new? What prompted that

Does the fan under the hood behind the radiator kick in when the dash coolant gauge gets near the red?

Does the top radiator hose get warm, ever?

There' are a lot of things that could be going on, given the information provided, that have nothing to do with the head gasket. Please provide a little bit of History and list what you have already checked before concluding head gasket.

Thanks.

 

Many thanks for the questions. Yes garage did some work on the coolant system a couple of years back, which replaced the radiator and hoses (due to age/leak). Yes the top of the radiator hose gets hot, and the heater seems to work well, so there is circulation. Engine does not overheat, the fan cuts in as soon as the temp guage exceeds half way and drops the temp a little. The overflowing occurs from the coolant reservoir when the vehicle has stopped. Took it to a radiator shop recently who did a pressure test, and cylinder compression tests, could not identify what the issue but suspected an internal coolant leak. I have replaced again recently the thermostat and the coolant reservoir to see if it helped. No sign of water in the oil, or oil in the coolant. I have not done a hydrocarbon test.

 

Where are you getting the thermostats? If from your local Autozone, Advance, O'Reilly or Carquest, I'd suggest you test them before installation. Most of the off the shelf stuff is crap nowadays. I'd get one from a GM dealer or GM parts site if at all possible. It MIGHT be that simple. As long as you're not seeing white smoke out the tail pipe and there's no indication of oil in the water or water in the oil, I don't think you have a head gasket issue. BUT I'm NOT a mechanic. I've just been working on my own cars for over 50 years. My current ride has 181,500+ miles on it. Regular scheduled maintenance is what I do.