Where is all of my fuel going?

[Kebo]

Hey all,

My pickup is a '93 W250 with a getrag swap and a low pressure piston lift pump. Recently, I was driving in the mountains unloaded and my truck started acting funny all of a sudden. I would get to 40-45 mph up a hill in 4th gear and it would cut out like it was running out of fuel to burn. I did some poking around. I removed the fuel shutoff solenoid, changed the fuel filter, and threw some BG44K injector cleaner in the fuel filter before I installed it. Same symtoms persist.

Tonight I hooked up a fuel pressure gage and fired the truck up. I took about 1-2 minutes to register that the pressure was 15 psi post filter. I then took it for a drive after bleeding the fuel system all the way through to the injectors. The fuel pressure gage drifted down as I accelerated through all the gears. Finally with 4th gear pinned the gage read zero. When I let off the throttle, the fuel pressure would return to 15-17 psi. Now my truck isn't turned up hardly at all. The fuel cone is rotated to the deepest part of the cone and about 2 turns on the starwheel.

Normally, before all this happened I had a slight haze at WOT and it felt somewhat peppy. Now there is hardly any smoke and it is a dog.

I'm at a loss. What happened?

[RCCUMMINS89]

Sounds to me like the lift pump went/going out for some reason.

[oldestof11]

Do you have a screen pre lift pump? It might be clogged

[CumminsPower59]

Do you have a screen pre lift pump? It might be clogged

This ^, X2. It is always best to run a strainer pre pump, looks like a old school in line gasser filter, but has different media inside to trap only large particles. FleetGuard makes a good one on the cheap.

[Kebo]

No screen.
Also, is 17 psi a little high for a VE pump?

[CumminsPower59]

I am seeing over 20psi, so you should be ok with 17...

[RCCUMMINS89]

When I swapped my fuel module over to my rc tank there was a screen in the fuel module inside the tank.

[bgilbert]

Two places to check for restriction between the tank and lift pump is the mesh inlet screen on the piston lift pump fitting and the pickup assembly screen in the tank. I had the same issues very recently. My inlet screen would plug very often/once a week or so. I added a cheap inline fuel filter thinking I just had some crap in the tank. Even before it would get dirty I would have the same issues. Ended up *cough* cutting a hole in the bed to access the fuel sender/pickup assemble, and the screen was 100% covered with what looked like vaseline, toilet paper and other debris. Fixed it and now have gone a couple thousand miles with no issues so far. I just keep a good eye on the clear inline filter right before the lift pump.

[Kebo]

Thanks, bgilbert. I will look into that. I have access to a forklift at work, so cutting a hole in the bed may not be necessary.

[Hansen01]

Dropping the tank is just as fast or faster than pulling the bed

[DodgeFreak]

Dropping the tank is just as fast or faster than pulling the bed

depends on if you have a full tank lol....my luck I always have problems after i fill it full of fuel.....so....i only run under half lol.....

[Hansen01]

true true

[CumminsPower59]

Dropping the tank is just as fast or faster than pulling the bed

depends on if you have a full tank lol....my luck I always have problems after i fill it full of fuel.....so....i only run under half lol.....

Half tank at best is all I can afford!

[PToombs]

Dropping the tank is just as fast or faster than pulling the bed

depends on if you have a full tank lol....my luck I always have problems after i fill it full of fuel.....so....i only run under half lol.....

Half tank at best is all I can afford!

That's just asking for trouble with condensation, especially this time of year with the big change in temperatures.

[CumminsPower59]

I have enough trouble going on around here, the truck is the least of my worries...