Newbie getting an 87 300SDL

[ahuggard]

A friend of the family is getting rid of his 300SDL and asked me if I wanted it. It is in good running shape, no visible rust, and he just had the exhaust done. I have wanted a diesel Mercedes for a long time and since this is free to me (paying for shipping), I'm ready to take it as is. While I have wrenched on old air-cooled VW's (68 ghia, 67 bus), this will be my first diesel and first MB.

A couple of quick questions for those who drive their older cars in wintry climes (W126 or other):

Aside from a block heater and a "well-adjusted" engine, what should I do to avoid gelling of the diesel fuel in the winter (I live in Milwaukee where it got down to -10 for about two weeks last year)?

At what temperature point should I not drive the car to work (where it is parked in a semi-indoor garage) and let it sit for 8-10 hours during the day?