Cheers for replys - the reason I asked is that I've recently flushed the Doblo with the proper stuff - it had a severe oil leak. By the state of the motor, I had my doubts that it hadn't been maintained properly for the last few years. My thoughts were that possibly, due to lack of regular oil changes, carbon/crud build up could be evident in some of the oil ways, hence pressure build up, consequently oil seal going. Who knows but thought it better to give it a flush out. Put two tins of engine flush it, then second blast with cheap oil (Asda £16) that wasn't cheap compared to the Halfords stuff that got discounted to £14+ odd - kick myself because I'd already bought the Asda before going into Halfords. Anyhow, noticed the flush stuff was very thin in terms of liquid viscosity. When it was drained out, also noticed how thin the old oil was, I was expecting the normal black thick stuff with lumps of crud. Put this info up on the Fiat forum and a couple of the guys came back with doing the flush with diesel.
Seeing the engine flush was £4 odd per 425ml tin reckon the diesel method would have been hell of a lot cheaper.