Outer Limits 4x4 Board

Hey guys got a major drama with the rangie its a 3.5 carb with a quadrajet that I have just fitted. It starts after a fair bit of cranking then stalls 5 seconds later. And it won't even start on LPG. Anyone got any ideas what could be causing this. I thought maybe fuel but that seems fine but not sure about the pressure of this when pulled off at the carby it just runs doesn't spray or squirt does this sound right. Its got spark. The starter motor packed it in just after fitting the quad so swapped out with a spare I have no idea what else it could be and I need to get this running ASAP.

Thanks
Kris

is it running really rich and flooding the engine with the choke on?

It has no choke but not sure about the flooding.

have you changed the jets? they are normally for a 5.0 engine not 3.5