hey dont trust the oily coolant. does the car slowly over heat? check your oil and smell it, observe it, does it seem as if coolant is mixed with your oil? then again, how much oil is floating around in the coolant? I recently did a swap and this guy was cheap, he didnt want to buy brand new gaskets (including a head gasket). i warned him and it didnt work, after flushing his cooling system 3 times, if you pop his radiator cap you can still see the oil floating in the coolant. its a bitch to get it completed out of the radiator..... maybe that head gasket blew and oil got into the cooling system. the car would still run fine and it does. but its a pain to completely clean the system. hey lesson to be learned = some things you cant be cheap on, you have to fork out the cash and replace, so do it to save on extra work, unless your getting paid for double labor and the customer knows the consequeces.