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Redland1

What I have been doing lately is running the lift pump longer before starting the truck and knock on wood it hadn’t done it again.

JimT

Maybe you have a small leak somewhere in the system, just enough to let air in while it's not running. You start up, hit the air pocket and stall. Next start the pocket is gone and it runs? Maybe the extra time running the lift pump helps eliminate the air? Or maybe the lift pump isn't as strong as it should be and takes more time to prime the system? I have a cm2250, not an 870 so I'm not familiar with the specifics of it's fuel system. Therefore this is total speculation and could be way off, but figured I'd share my thoughts.

Redland1

Yeah definitely haven’t had the issue since I have been running the lift pump longer.

Redland1

The truck didn’t want to start this morning and after running the lift pump a couple of times it cranked and had a funky idle.Hooked up Insite and code 951 was showing (cylinder power imbalance between cylinders) and the troubleshooting tree shows check for air being ingested into the fuel.Looks like Jim T and Nilao were onto something.Besides the fuel lines where else can it get air from?

Rawze

* do an overhead valve adjustment followed by an injector leak test. make sure no injectors are back-feeding pressure from the cylinders .. causes same symptoms as air in the fuel.

* Check fuel lines by pressurizing the fuel tanks to 10 psi and letting it sit for a couple hours.. look for dripping fuel.

* Check to ensure the pick-up tubes in the fuel tanks are not cracked at the top.

ref: http://rawze.com/forums/showthread.php?t...9#pid53259

Redland1

(07-18-2021 )Rawze Wrote: * do an overhead valve adjustment followed by an injector leak test. make sure no injectors are back-feeding pressure from the cylinders .. causes same symptoms as air in the fuel.

* Check fuel lines by pressurizing the fuel tanks to 10 psi and letting it sit for a couple hours.. look for dripping fuel.

* Check to ensure the pick-up tubes in the fuel tanks are not cracked at the top.

ref: http://rawze.com/forums/showthread.php?t...9#pid53259

Overhead set was done a few months ago.

I do keep finding fuel residue around the pickup tube area and also around the saddle but the saddle is unrelated I believe and it’s probably rubbed a hole in the tank.Going to loosen that saddle when I get home and take a look. Does the residue around the pickup tube in the pic seem like that might be the issue?

JimT

While this is outside my area of knowledge, I'd say the top of the pickup and fittings to the fuel line are probably a good place to start. Anywhere fuel could leak out is a point where air could get in. It's clear you have some sort of leak in that area so it's a good place to start.

Also, it would be prudent to check the overhead again. There's always a chance that a mistake last time could have caused the problem you currently face.

Redland1

(07-18-2021 )JimT Wrote: While this is outside my area of knowledge, I'd say the top of the pickup and fittings to the fuel line are probably a good place to start. Anywhere fuel could leak out is a point where air could get in. It's clear you have some sort of leak in that area so it's a good place to start.

Also, it would be prudent to check the overhead again. There's always a chance that a mistake last time could have caused the problem you currently face.

What would be the easiest way to rotate the tank to pull out the pickup tube if need be?

The overhead was done by a shop since I don’t have experience doing it and honestly I don’t have an idea how good of a job they did.Should I take it to another shop and have it redone? Like Cummins,or the bigger dealerships.

Waterloo

(07-18-2021 )Redland1 Wrote:
(07-18-2021 )JimT Wrote: While this is outside my area of knowledge, I'd say the top of the pickup and fittings to the fuel line are probably a good place to start. Anywhere fuel could leak out is a point where air could get in. It's clear you have some sort of leak in that area so it's a good place to start.

Also, it would be prudent to check the overhead again. There's always a chance that a mistake last time could have caused the problem you currently face.

What would be the easiest way to rotate the tank to pull out the pickup tube if need be?

The overhead was done by a shop since I don’t have experience doing it and honestly I don’t have an idea how good of a job they did.Should I take it to another shop and have it redone? Like Cummins,or the bigger dealerships.

Rawze has a video on running the overhead, you only need a few tools, easily found on Amazon or most auto parts stores. Largest item is a bar/ratchet to turn over the motor with a short 3/4" extension, Harbor Freight most likely carries those or a NAPA store. The feelers, crows foot and torque wrenches are available at again, most auto parts stores. I use the inexpensive Tekton torque wrenches and a small newton meter boom to do the injectors, AutoZone sells that small boom torque wrench, same with the feeler gauges.

That fuel tank, best to have it empty, so hopefully there is not much fuel in it, or you probably not even budge it. Just loosen the tank straps, watch the fuel lines and other connections and rotate. You may have to do some line disconnection, but as long as the tank is empty, it is pretty straight forward.