Wow! Thanks for all the responses.

Here are the particulars...

MN: BF03A35V
Chassis #: BF03-920299

I did mean the vaporizer. It is an Impco Model L. The regulator is a VFF 30. Is there a mixture adjustment on the carburetor (not sure if that's what it's called on an LP system)? There is a large screw near the top with a spring on it. I think one of my guys has messed with it since it is almost bottomed out. Is there some sort of "starting point" for this adjustment...if that is what it is?

The truck runs great once it's started - it's just starting that is the issue.

Thanks!