QuestionGood day to you sir. My father's old bmw has a problem with it, there is fresh looking oil in the expansion tank but the engine is clean, no slugge. The car does not overheat and there's no dirty blue or grey smoke coming from the exhaust. The car is running fine. Also my dad has never topped up the oil level in a year it's always spot on. The car has had a head gasket about 8 years ago, the head was sent away for inspection and skim, it came back ok as expected. My father does very low milage, guess less then 2000 a year. Thank you.
AnswerA lot of oil, or a sheen of oil?
Has the oil level dropped in the sump?
Has the transmission fluid level dropped (if auto). (I'm not farmiliar with this car, though I suspect the cooling for the auto box and engine are closely linked, enough to contaminate each other if damaged - maybe)
Has there been antifreeze in the car over the bad weather? do you know if it froze without antifreeze?
Possibility of accidental contamination?
I would not be surprised at a second failed head gasket.
If it is a small amount oil- Run the engine till the fan kicks in and out again, check the coolant and oil during+after this. If everything seems healthy give it a good rev.
If it's no worse, everything feels healthy, it runs smooth through a heat cycle and it is not sludging up; let it cool fully, flush out the cooling system - including operating the heater during the flush, refill it with reccomended coolant and hope for the best.
