So did a new thermostat fix the problem?

I know it sounds paranoid, but before I put a thermostat in anything I always dunk it in boiling water. I'd rather take the 5 minutes to test it than have to drain & refill the cooling system again after having to change a defective thermostat!

With no thermostst it runs 150-170 no problem.

I'm gonna get another thermostat (not a Mr Gasket) soon since I dont want it running that cool, but it will work for now....... I think I'm gonna pre-test this one first :)

I had a MR.Gasket thermostat that would stick closed also. I don't think Ill buy another one from them again.