Purging Air after Conversion

Hey Peeps,

I’m sure this has been covered at length but I’m having trouble finding it. If I am trying to purge the air from the fuel system (to finish a conversion)....how long should it take. I played with it for like 20 min the other day and drained the battery (which was already weak). I gave up thinking maybe the lift pump wired correctly. Of course upon further reflection, there is no lift pump.

Just curious how long I should expect this to take?

I am guessing you do not have a mighty-vac or the equivalent; that would be the easiest and fastest way to eliminate air. Don't forget air in the pump discharge lines will compress and not let the fuel pass into the injectors.

It shouldn't take too long at all. I gravity fed the pump from a small container and cracked the injector nut on all 4 lines. Cranked it over 4 or 5 times until I saw fuel from all 4 injectors tightened up the nuts and away it went. Might have taken 5 minutes total. A lift pump makes it even easier, well worth the time to put one in in my opinion.

With a mity vac, I could have a car running in 5 minutes or less given a dead, empty and dry fuel system. (providing every thing else was in good working order). No cranking required until the pump is full of fuel. Then with the injection nuts cracked, i crank until i get a spirt from the back side of the nuts. Tighten them down, and away she goes.

Yea in hind sight I probably should have just plopped in the lift pump from the gasser. Might still do that at some point.

Ok so I didn’t gravity feed the pump...and there is still a visible air bubble in the clear line between the fuel filter and the injection pump.

Only reason I gravity fed it was to get the pump casing full of fuel, just my way of doing it.
Does it run now? I wouldn't worry about the air bubble if it does, drive it and see if it goes away after running for a bit.

^^I'm with Exenos. Just run it. If it doesn't clear on its own you'll have to look for an air leak.