Fuel issue, idle's fine but dies when you give it throttle

[Claychevycd]

Hey guys I'm new to the site and I've looked through the other post with some similar but not quite the same issues as mine. It started when I went to a tractor show with a load pulled fine all the way there and halfway home. The truck started getting weak and then got to the point where I used low range to get up a few hills (small ones). It idles fine,it will idle all day if you want it to. I put a new filter on before the trip and again after the issue. If you let it sit and idle you can go about a quarter mile before it dies. It has an electric fuel pump that work great and there are no air bubbles at the bleeder. Any help will be much appreciated.

 

[ke6rwj]

The lifter pump is electric instead of mechanical?

you say it dies, does it die under load or also when in P or N and reved up?

Does it die when you goose it?

 

[Claychevycd]

Lift pump is electric.
dies under a load, but if you let it idle you can limp your way home.
will rev up in park or neutral
It goes when you goose it then falls off.
tried a trip down the road this morning, got to a good down hill stretch and put it in second and floored it ran good for like 3 seconds and then died and was blowing blue smoke. Put it back in drive and coasted a ways and let it idle and was able to get home.

 

[GM72K10]

I bet you have a clogged fuel tank sock. My M1028a1 ran like yours and here's why. Dropped tank, changed sock, no problems since.

 

[wrenchturner6238]

Is this a 6.2 diesel?

 

[markg]

Hello, i would check two things. first, pull the return fitting on the top of the ip, make sure its clear, and that there is no trash in the fitting. blow compressed air through it. second, pull the fuel line in front of the lift pump and blow back to the tank. we will go from there. good luck, thanks. mark

 

[wrenchturner6238]

I agree on some of the old 6.2's they had a rubber governor ring and it comes apart after a while in the diesel fuel and plugs up the return fitting.

 

[Claychevycd]

Already checked the fitting on the IP, and I blew threw the line to the tank also.
the fuel tank sock sounds plausible but it sucks because it is all the way full of fuel. Thanks for the advice.
I opened the bleeder with the switch on and it starts out with a strong steam of fuel and the slowly decreases.

 

[ke6rwj]

its a fuel volume issue from a restriction of some type. I would check the returns, fuel filters including the sock in the tank as mentioned. If you've done any work lately make sure you didnt kink any lines.

 

[ke6rwj]

Already checked the fitting on the IP, and I blew threw the line to the tank also.
the fuel tank sock sounds plausible but it sucks because it is all the way full of fuel. Thanks for the advice.
I opened the bleeder with the switch on and it starts out with a strong steam of fuel and the slowly decreases.

Ok now go one step backward to before the fuel filter and see if its the same flow rate. did they bypass the mechanical lifter pump when they installed the electric lifter?

Full of fuel, yes.. that sucks, however, you need to do the sock anyway, better now than on the roadside somewhere.. thats how i usually convince myself to stay positive..

 

[Claychevycd]

Will do. Gonna drop the tank as soon as I have time and change the sock. And work back toward the IP. Thanks for all the help guys.

 

[Claychevycd]

Yeah I put the lift pump on and bypassed the manual pump, and went ahead and put a 6.5 block off plate with oil return on for when I get a chance to do the turbo. Every time I start getting proud of the truck it goes and shows it a$$ like this in some way.

 

[wrenchturner6238]

Fuel tank problems for me always happen right after they are plum full!!

 

[Claychevycd]

O' great now it's snowing for the first time in three years and my p.o.s. Is out of commission. Lol

 

[top_prop]

How are you doing on this one? When my truck started fuel problems I used the electric pump to pump out as much fuel as I could. Also there is a syphpon fitting on the original fuel sending units you can use to syphon/drain the tank.

heres the thread I started on the process of replacing my tank...

http://www.steelsoldiers.com/showth...clogging-fuel-filters-Sand-in-fuel&highlight=

 

[Claychevycd]

Well I got it all sorted out. I dropped the tank cleaned it out (pain in the a$$) because of these big hands not fitting in the sending unit hole, but got it done. Took the strainer off the pickup tube and bent the pickup tube up a little off the bottom of the tank until I get a new sending unit. I'm running a inline pre filter before the inline pump so every thing is all good for now. I've been a 90 mile round trip and all went well so it's good to go.

 

[paladin1176]

Good to hear. I am getting ready to do the same thing to mine to fix pretty much the same problems. How did the sock look when you pulled it out of the tank?

 

[Claychevycd]

It was covered in this grey metallic sludge, and apparently when they assemble the tank at the factory they leave clumps of solder.

 

[paladin1176]

Did you find just a strainer or did you replace the whole sending unit? LMC sells the whole unit with fuel gauge assembly and new filter, but the filter looks like it's almost cheese cloth. I was expecting more of a metal mesh as opposed to a flimsy cloth. Checked with AutoBone and NAPA and they sell the AC Delco strainer, but again it looks fairly....wimpy.

 

[Claychevycd]

It's like a white nylon material with a steel bung woven into the strainer, and it's brazen or soldered on the pickup tube. The easiest way to fix it is to buy the whole unit from O'reilly auto for $60 bucks. Make sure you get the one with three lines on top. I've got a spin on filter and housing i need to put on now, got it at NAPA.