About an hour after we transfered the title of a 97 blazer i was driving to my softball game and the car overheated. At the gas station I added coolant. After about an hour I continued home to find that the temp gauge was warmer than it should have been. Upon arrival I got out and heard something, I opened the hood to see boiling in the coolant resevoir? Parked for a night, following to day I went to my insurance broker to get a quote by the time I made it to the office the car was damn near about to overheat again, obviously I parked and got out to find that the resevoir was boiling again. Does anyone have a clue what triggers this reaction?

 

It is not boiling, but the radiator is pushing air/steam into the reservoir due to the overheating condition in the engine. I am not sure of what the cause of your overheating problem is as you have not provided enough information for that diagnosis, but you likely should start by replacing the thermostat and radiator cap. Check your oil for signs of coolant and possibly have your cooling system checked for leaks. Air in the cooling system is not a good thing and you should do whatever you can to get as much of the air out as possible.

 

A friend hooked up a pressure meter and confirmed that there is a leak and there is nothing on the ground so we are assuming it is going into the engine most likely through the head gasket. Hopefully not that would be an extensive fix.

 

Well, do let us know what the eventual repair is so that, if nothing else, others can learn from your experience.

Good luck!