OhSix· Premium Member
Have no idea if this has anything to do with your issue but... the water round these parts is heavy with calcium. And a lotta folk use tap water to fill/top off their cooling systems. I've seen build up to the point valves, thermostats and passageways have frozen or clogged up to the point where issues like yours have developed. As Dnick suggested, the only real way to deal with junk along those lines is disassemble and clean up or replace. I know, it sucks.