Bleeding the fuel system

[bplust]

Hi all,

I've recently replaced some fuel line, and was wondering how to bleed the air out of the fuel circuit. I've located the bleed screw, and am wondering if there is a hand operated primer pump, and if so, where it is located. If there isn't a hand pump, what is the proper method for bleeding out air in the lines?

Thanks,

Bryan

[5.9fan]

The hand primer is located on the lift pump on the side of the block. Its the one that looks a bit like one you would see on an old carbureted car. Open the bleed screw above the fuel filter and pump the primer untill air free fuel comes out. It is going to take quite a few pumps to get all the air out, so keep at it! Fuel will start coming out with air, so put a drain pan underneath and let it pump untill there is little to no air and just fuel. then close the bleeder. loosen all six injector lines a few turns at the injector ends and turn the engine over. you should soon see steady spurts of fuel, again letting it go a bit more than absolutely necisary is ok, the more air you ge out, the better. then tighten the injector lines and start the truck. it may run rough and blow some white smoke for a bit, but it should even out in about thirty (30) seconds. Durning this time, you may have to keep your foot on the accelerator to keep it running. Going over 1/4 throttle shouldnt be necissary.

[bplust]

Thanks for the detailed response!

I have one question: Should I turn the engine over with the key (but of course not start it, just turn it over) or should i use a wrench?

[5.9fan]

Use the key. With the injection lines loose for bleeding, the probability that the engine will start is low, and even if it does, just shut it back off. More than likely, if all the other bleeding goes well it will begin to fire on one or two cylenders after only a couple of revolutions. Either way, tighten the lines down once they all seem to be spurting strong and sheel be ready to go.

[bplust]

Hey, thanks for the reply!

Another question:
I located the pump per your instructions. It's a little tab that you can move back and forth. My pump will stay in any place you leave it within its range of movement; not that I've seen every primer pump out there, but ones that I am more familiar with tend to return (spring) back to one position after you move them. Also, no matter how much I pumped (50+ times), nothing came out of the bleeder. Is the way that I am describing my primer that of having the symptoms of a defective one?

Thanks again,

Bryan

[5.9fan]

The fuel pump is operated off a lobe on the camshaft. Right now the actuating lever is resting on the peak of the lobe. Bump the engine over with the stater. it only needs to make a good rotation or two. that should do it.

Make sure the little lever is in the 'up' position before turning the engine over.


Im glad I could help!