HMMWV Rough Idle, Surging now Dead no Restart.

[Retiredwarhorses]

Can i drop a stick down the filler neck worse case for a fuel level check? I have zero faith in these military fuel senders.

not a stick, but something flexible, yes...you can even use a skinny hose and try and syphone.

 

[UserError]

Alright. Well we at least know the sender is 100% full of crap. Tank had about 5 gallons or so of Diesel Scented 10 weight sludge in it. My driveway was not amused, but it ought to keep the dust down

There is a screen in the filler neck, so i couldn't drop my fuel thief down there and suck it out.

Ordering a new tank bung plug thing now, anyone got a line on the fuel level senders? Part number perhaps?

Im half tempted to drop the tank and see if there is a fuel sock or any type of pre filter in there that needs to be replaced, along with the sender.

 

[UserError]

Flushed the tank, clean fuel. Blew out the lines. cracked a couple injector lines open got it to restart.

The fuel pump output seems pretty good. When the lobe comes around there is a pretty healthy shot of fuel. It comes in spurts, not a steady stream.

Idle is very rough. Some white smoke. Im assuming it still has air in the pump/lines/injectors.

Do i need to go around and crack each injector to bleed the air out? Or should it clear up on its own with some running?

Also when running, the return nipple is just barely dribbling fuel out with the return line disconnected. Should this be more of a stream? Is it indicative of needing replacement of the fuel nipple?

I think I'm back to where i started before it starved out and died, which was a rough running truck. Clean fuel. Clean filters. Whats next? Bleed air? Return Nipple? I would like to get as many things sorted as i can, before i pull the injectors to have them cleaned and popped/shimmed or rebuilt.

 

[Retiredwarhorses]

Flushed the tank, clean fuel. Blew out the lines. cracked a couple injector lines open got it to restart.

The fuel pump output seems pretty good. When the lobe comes around there is a pretty healthy shot of fuel. It comes in spurts, not a steady stream.

Idle is very rough. Some white smoke. Im assuming it still has air in the pump/lines/injectors.

Do i need to go around and crack each injector to bleed the air out? Or should it clear up on its own with some running?

Also when running, the return nipple is just barely dribbling fuel out with the return line disconnected. Should this be more of a stream? Is it indicative of needing replacement of the fuel nipple?

I think I'm back to where i started before it starved out and died, which was a rough running truck. Clean fuel. Clean filters. Whats next? Bleed air? Return Nipple? I would like to get as many things sorted as i can, before i pull the injectors to have them cleaned and popped/shimmed or rebuilt.

Your going to have air till its bled out...start the truck, crack one easy to get too injector, they all don't need cracking.
white smoke is unburnt fuel...you only get dribbles from the return lines and the cracked lines only kinda dribble as well, it's not going to shoot out like crazy, that's the injectors job.

 

[UserError]

I meant the return fitting on the top of the IP, in front of the shut off solenoid.

Where do i go from here to figure out why it runs so rough and crappy? i guess i need to crack lines on at a time till i find the troublesome hole. Def sounds like the drivers side of the motor is running rougher than the passenger side bank.

Most the white smoke was diesel burning off the headers that i had sprayed everywhere. Its not smoking anymore, but doesn't run any better than it did before it starved out. Im assuming it was sucking air sitting on an incline and didnt have much fuel in the tank which caused it to starve out. Ive got 5 gallons in it now, going to dump another 5 in it to make sure the pickup is fully submerged.

 

[dilvoy]

Well, you might replace the fuel hoses since you are going through the system. Might be cracked or loose near the fuel tank and sucking air. Even if it isn't, the fuel hoses have probably been there for a long time so a change would be a good safety item to check off of the list.

 

[Action]

it reads like you never read any of the posts.

 

[UserError]

lol i read all the posts. this is just more me thinking out loud. RetiredWarHorses hit the nail on the head and the truck was starving out. Im a jackass for not verifying the fuel level in the tank. it was indeed sucking air and lost prime. With the lines blown out, the filter replaced, the tank drained and cleaned, clean fuel it started back up. And now its back to running as horrible as it ever did. This truck has NEVER run well since i owned it.

The truck has at least a couple bad injectors. One of them unscrews before the fuel line will break loose... this ought to be a unique challenge. Of course, its not one of the "easy" ones to get to either. Probably why it was never installed correctly in the first place.

I did a chemical "block test" today, head/gasket are good. Ive got to get the injectors or glows out to complete a compression test.

Do you guys remove the lines to get the injectors out? Or just loosen them and push them off to the side?

On my cummins trucks i always remove the lines completely before messing with the injectors, so i don't bend the lines. On this rotary pump it seems like i can't get to the bottom fuel lines without removing the pump itself.

Are you guys removing the entire injection pump prior to pulling the injectors out the heads?

https://www.youtube.com/watch?v=lRdY_xTDRm8&feature=youtu.be

 

[Retiredwarhorses]

You don't need to remove the injector lines from the pump.
just move them to the side. If the one inj is turning, the body of the inj is loose, this it's sucking air.
put a wrench on it and hold it so you can loosened the line. Channel locks or vise grips will work.

 

[Retiredwarhorses]

The injector on the top half where the drain nipples are will unscrew from the bottom nozzle.
the top has 4 sides, so you can get a wrench on it, 7/8 open end wrench

 

[UserError]

The entire injector was unscrewing from the head, not the body from the other half of itself. I did just what you said, got an adjustable wrench in there to hold the top half the body and loosened the fuel line.

It was WAY over tightened. Im going to have to replace that injector line, in order to clear my conscience. Seems someone tried to tighten the loose injector by wrenching the crap out the injector line nut.

I started on the passenger side, i figure it would be the more difficult side. Suns coming up and its getting HOT outside. now I've just got to go find a 30mm socket and finish popping these little dudes out.

Progress is made, an inch at a time.

 

[Retiredwarhorses]

I just threw away a set of 6.2 Inj lines...bummer. If your going to pull all of them out, put in new drain back lines.

 

[UserError]

drain back lines are the little rubber ones right? Those things are shot. Many of the micro clamps are long gone. Ive heard of a line kit that doesn't use those little spring clamps, but I'm not sure who makes it.

Im having a hard time finding injector lines too! bah! lol. just my luck! I always thought parts would be easier to find out here than when i lived back east. not so I'm afraid.

I got the 4 pass side injectors out, then called it a day as the sun was melting my brain. Even this close to november its still pushing nearly 100 degrees out here.

 

[gestut]

Can i drop a stick down the filler neck worse case for a fuel level check? I have zero faith in these military fuel senders.

so what ever happened , did you figure out the problem? i am having a similar issue (just got the truck delivered) , and going thru the test that retired war horse has mentioned, my batteries went dead trying to crank it.