The main thing to remember is : this is the Chrysler Air Temp II system used under license .

There are several manufacturers still making the evil servo, I bought the alloy bodied one and it was fine, some of them leak even though new .

Pretty much any crud in the cooling system will cause the servo to jamb up sooner than later, red / brown coolant is a BIG red flag, if you see it, get busy cleaning and flushing NOW, doesn't matter if it's Summer, suffer the heat of proper flushing as the servo traps sediment, binds up or drags, causing the amplifier to burn out or the Bakelite servo housing to crack and leak out all the coolant whilst you're driving along.....

I hate this system greatly but once working it's wonderful, until the next time it fails .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better