On Sun, 22 Feb 2009 18:34:36 -0800 (PST), P
wrote:

I have a source for natural gas, but it's unlikely to be usable in the
rotax's. Or anywere.

It is the gasoline usually produced along with the gas. I remember my
uncle taking the five gal cans out of the trunk and filling them.There
was a length of 1/4 inch copper tubing with a valve in it, coming out
of the nest of pipe at the wellhead. Thay call this casinghead
gasoline.

Casady