Expert: Vern Bullock - 9/19/2008

Question
im having an issue of coolant puking out of the overflow tube after about ten minutes idleing in my driveway. the radiator has been taken apart and rodded-out etc..., new 180 thermostat, new 16lb cap, new upper and lower hoses, and a new water pump. no water in oil, no water/steam from exhaust. temp gauge in car is at halfway when overflow begins puking coolant. both sides of the radiator are getting hot. coolant is a 50/50 mix with water. car has a clutch fan. ive had the car two weeks and have never taken it out of park. id love to be able to drive my dream car please help.

Answer
Hi Brian:
After reading what you have done, I begin to think you have covered everything that could be causing this. However, let me add one more possible cause of this problem...

Did you flush the engine and radiator? You could have some blockage in the engine or radiator. If you have ruled this out, then if the amount of water that is coming from the radiator is not much (e.g. an oz or two), then you would have a weak gasket, even if there is no anti-freeze in the oil or steam coming from the exhaust.

I have this problem with a recent car I purchase that had sat for two years, and I was about to have a mechanic treat it with a new Stop-Leak process to seal the gaskets. Lucky for me his shop was about 50 miles away and by the time I arrived, it had sealed itself and that was a year ago.

So, driving her may be the answer. Especially if she has been sitting for a long time before you got her. Hope this helps.