The bio-diesel really needs to be mixed with dead-dino-diesel. Pure McDonald's
diesel reacts badly with the synthetic materials in the fuel system, (hoses,
etc).

I burn an 80/20 mix. 80% dead dinosaurs, 20% artery clogger. They sell it at
the fuel dock. It's about 25 cents a gallon more than straight dino-diesel, but
it makes a small contribution toward a better environment.