All,

Many thanks for the help!

Regarding coolant - appreciate the advice and specifics on the brands! I have not yet replaced it since I bought it. I am installing a coolant heater for my SVO so it will be changed soon!

The glow plug relay is shot there is a sizeable bulge where it melted. Unfortunately I have a 1980 with the large box relay (Mercedes PN 1235401545). They are hard to find and appear to all come from Mercedes for $450+ new. I have seen a kit where a BIG manual solenoid is used in place of the relay. Any thoughts about this MUCH CHEAPER option?

Thanks again!

-matto-