I'm sure most of you have seen what these go for new, and if the one you got is spewing coolant across the floorboards of yr amazon then it may seem well worth it. It seems though, that the most common ailments are that they either freeze open or shut, so that heat is either on or off permenantly. Mine is frozen open so that there is always hot coolant going thru the heater core, which i assume is a little bit favorable because i would figure that if it seizes shut is when it will start blowing fluid in the car.

For a while now, I have simply, hooked up the heat in the winter, and unhooked the hoses to the heater core/valve in the summer. But I have been thinking on what caused this (besides simply age) and i think that the deposits of years of antifreeze/hose water have accumilated within the valve. I was talking to a friend about soaking the valve unit in a jar of CLR lime and rust remover and he suggested just using vinegar as it is a much less caustic acid and less likely to eat the rubber/whatever else that's inside that little bugger.

Has anyone ever tried bringing one of these back to life? Any ideas?