1990 460 propane issue
 

Hey guys, my truck recently decided it didn't want to start on propane... It's a 1990 f250 460 with dual gas tanks as well as dual propane tanks. Last time I ran it on propane was about two weeks ago, It kicked back a couple times and was sputtering, and wanted to die. I turned it off, it fired right up, but then started to die again. I would give it gas (propane) which would keep it alive for a bit, but then it would die. Then check engine light came on and kept dying. I switched it back to gas, ran fine, didnt studder, check engine light turned off. Ive been running it on gas the last two weeks and its had ZERO problems. But now it wont start on propane. Ive heard that the propane freezing is a problem, as well as something to do with the regulator. I let it warm up at idle for 15 minutes and it was about 5 degrees celsius out.

thanks in advance

Jared

with a properly functioning cooling system, and an ambient temperature of 5 celsius, its unlikely your propane regulator has frozen up.

1 possiblity is that your (gasoline) fuel shut-off solenoid is malfunctioning, flooding your engine with 2 fuels, instead of 1.

Ok I will look into that. And you're saying that's why it's not starting now right? Not why it was sputtering and kicking back.

Jared

No, he's saying it's a possibility. You need to determine if what he's saying is actually what's happening. To me, the simplest way would be to pull the relay or fuse for the in-tank fuel pumps (thereby eliminating the chance that any gasoline is being fed into the cylinders) and then try to start it with just the propane. If it starts and runs fine, then that's confirmation that there's a problem with flooding.

If it doesn't, then there's probably an issue with the propane system. But, not knowing anything about propane systems, I can't give you direction on it.

Please post info/model #s on the equipment on your truck, pictures would be nice also.
First guess is the vaporiser is leaking thru and will nee to be rebuilt. If you have a hose the goes from the vaporiser to the mixer/carb pull it off then turn the key to on or supply vacumn if you have a vac fuelock. If get fuel its a bad regulator

regards

Ok I'll look into the model # I just bout the truck and have no idea how propane works at all. It was converted back in 1992... I have a friend moving back to Vancouver this week and he is much more mechanically savvy than me. I appreciate the feedback from you guys
Jared