I just had an overheating issue with the 85 300SD which I have sold to my daughter. I changed the stat (a chinese made one which must have come in it) and am crossing my fingers there is no other issue with the engine. My question is with the nasty rusty looking coolant which remains in the system after draining all I could without major effort. Is the rusty water look just a cosmetic issue or do I need to flush it really well?

__________________
[SIGPIC] Diesel loving autocrossing grandpa Architect. 08 Dodge 3/4 ton with Cummins & six speed; I have had about 35 benzes. I have a 39 Studebaker Coupe Express pickup in which I have had installed a 617 turbo and a five speed manual.[SIGPIC]

..I also have a 427 Cobra replica with an aluminum chassis.