Burbert
Guest
I don't think that Black oil is any sort of problem at all. The important thing is to keep changing oil and filters at regular intervals. In our diesel engines, tractors and combine, when the oil is really dirty, it is Grey also, not just Black, which is a good thing, it means the oil is cleaning as well as lubeing. One time we did flush out our 30_10 JD tractor, by putting in some diesel fuel in the crankcase after draining the old oil and rolled it over a few times (DON'T START IT THOUGH!!!). I don't think that the procedure made a lot of difference.