FL1BY

2001 Coupe, Stock engine. 140,000 miles. No milky water color in the oil. No new or unusual valve train noise. Had to change a water pump hose due to a pin hole from chafing.

Yesterday while driving the coolant tank to thermostat hose connection cracked at the reservoir. I replaced it and now when the temperature gets to 205-208 degrees I have a geyser of hot water shoots up from the coolant reservoir, 10 - 15 seconds. Faulty thermostat? Head Gasket? No white smoke, no loss of power. Any ideas? Maybe just air trapped?

vettenuts

I would start simple and make sure the system is properly filled and no air is trapped. If that doesn't correct it the thermostat would be the next thing I would replace. You can also have the coolant tested for exhaust if you suspect a head gasket, which doesn't require any dis-assembly of the motor.

dgrant3830

If you are getting a sudden burst of air/coolant out of the surge tank then nothing again, its probably a bad thermostat. It might be ruined if you used cold water into a hot engine or similar event. If it was a blown head gasket, you would have constant air bubbling into the surge tank. To be sure, there is a test kit available at Napa that will test for exahust gasses in the coolant but you need to run the car up to temperature with the cap off in order for the test kit to sample the air/gasses. Yes, it could be trapped air too causing things to happen.