89Ford73, maybe you just answered your propane problem! You said that you have 3 small holes in the copper tubing in the air cleaner for the propane to flow through, maybe it just needs to be opened up more. I have 12 - 1/16th" holes in mine and a friend of mine has 14 - 1/8" holes in his and we have both had good results. Might wanna try drilling a few more holes in the tubing to allow for more propane volume to flow (pressure = flow through a restriction).

Just a thought.

Bowedup