Chuck:
You are correct about filling LPG tanks. The tough ones are the Liquified Natural Gas ones. Hard to find a place to fill them, the fleets that used it had their own filling equipment to take the gas out of the gas line and pressurize it into a liquid and into the vehicle's tank.
At my shop I used to service a local LPG company's bulk truck. They ran it off the big tank on the back of the truck. The engine stayed clean as a pin inside, but the exhaust manifolds had to be changed regularly. They would be reduced to crusty, rusted junk in a fairly short time. The oil drained at change time would be just as clean as when it was new.
John in Selma, IN
John - "The Hoosier Hurricane"
