I'm having a battle of wits with this forklift and it's painfully apparent that I'm under gunned. I'm also not that familiar with lp fuel systems.

It has a Nissan H-20 engine that will start right up, and idle just fine, but surges anytime you step on the gas pedal. It doesn't matter whether the engine is warmed up or not.

It has an Impco ca125 air valve, a VFF30 fuel lock, a model J regulator, and a Koshida pneumatic governor. The coolant level is ok, I've put a kit in the fuel lock in order to get a new filter in it. And I've cleaned out the air valve. I've been able to find just enough info on the Impco parts to become somewhat familiar with how they work, but I can not find a darn thing on that Koshida governor.

Can anyone tell me what to look for next?

Thanks,
Scotty