Only if it has been oiled Mike,,
..Seriously, if you have gotten some oil in the cooling system, you've got to locate the ingress point (usually bad headgasket), fix that first, drain the cooling system, discard thermostat, refill cooling system with water and a good detergent (Benzmac recommended SHOUT, run it till it's warm, drain it again and flush it with clean water, refill with coolant and be happy..
OOPS, don't forget to put a new thermostat back in...
1987 BMW 325
[This message has been edited by jeffsr (edited 04-08-2000).]