I have just purchased a Toyota Mod. 40-5FG25 forklift that has propane fuel. I is a 4Y engine.
This was an "AS IS" out of a lease/rental fleet. It is 100% complete, less the tank and mount.
I did compression cold tests before purchased and it was 190# on all cylinders. Plugs were clean.

I brought it home and put a full tank of propane on a mount I made. Properly positioned with the locater holes down. Removed the tank hose and blow it out before installing a new tank connector.

Cranked over fine and tries to start but runs like it is out of fuel. Will keep firing and miss firing as long as I keep the starter engaged. Once I got it to run "rough" without the starter engaged and about half throttle but it was rough and would pop back into the intake occasionally. Evenually died but did run long enough for the coolant to warm up and I noted the frost on the propane "stuff" melted. Haven't been able to get it to run continiously since.

The only adjustment I have been changing is the large head screw on the side, towards the top of the throttle body. This is a IMPCO model 100 system and everything seems to be hooked up and the vacuum lines, etc. check out ok.

I just don't know anything about propane systems or trouble shooting.

It could be ignition but it has one of those distributors with the coil pack built in. I plan to check it out next to see what type of components it uses.

If anyone could provide me with some direction on trouble shooting and adjusting this propane system, or even a link to a reference manual on this. I would appreciate it.

Thanks
STEVE