Thanks guys so far. I need to go out of town for a few days but when I get back, I'll check the thermostat housing and let everyone know. I am hoping it is just this simple. Again, no problems with the 160 degree stat - I may just have had a better gasket seal at that time, and now I don't. Also, I always make my own cork gaskets for that one, and don't use RTV sealant. I will check the housing and then also use RTV sealant. We will see. Bye for now.