I have an old nissan 30 forklift that ran out of propane the other day. I took the tank down to refill. The tank started to spurt liquid through 20% port at about 7 gallons. He closed the 20% port and put another gallon in it, before turning off the refueling machine and disconnecting.

I reinstalled the tank and no start. I thought he might have overfilled it, so I opened 20% **** until no more spray was coming out. Still won't start. I have 2 impco converters in series and both don't have the push button. I pulled the fuel output line at the carb and it starts and appears to continue while it is getting vapor but after a couple seconds liquid will come out of hose.

My guess is the converter is bad. Questions are was it caused by overfilling the tank? And what is the purpose of the 2 converters in series and how do I determine which is bad?

Any help will be greatly appreciated