I am new here but I thought I might mention that I been running my P38 Diesel RR on home made Biodiesel for almost a year. It seems to like it fine enough. I get better fuel/mileage returns and it seems a little more lively. I run on 100% bio but I do put a small amount of unleaded petrol in each time I fill it, just to help in the colder weather (stop it from gelling)
I get the waste oil from 2 sources, the main one being our local fish and chip shop and other from a cafe where they train youngsters with learning difficulties. (that gets delivered to my door!!) In case anyone is interested the engine in the Rangie is a BMW M51 with a VP37 injection pump.