6.5l diesel help

[picc53]

my truck can idle for hours but when i go and drive for more than 30 mins it will stall out on me. It will start back up again if i let sit for like a min. Is the lift pump not working right I open the bleeder on the filter but nothing comes out. i check to see if lift pump is working it feels like it is pumping but how come no fuel coming up.

[gmctd]

Welcome to the forum pic........

Check the fuel filter, first, and clean out the cannister, making sure the t-drain is open and clear.

The lift pump is a solenoid-operated shuttle with two one-way valves - the plastic valves fail, but the shuttle still does it's thing, which makes the vibration\noise.

Probably time for replacement

[sailun]

This is probably NOT your problem, but I had the same problem on a sailboat of mine. (32 hp Kubota/Universal motor).

Would idle forever, or run up to half throttle, all day long. But, when you pushed it, it would suck the Racor filter dry, and stall.

Opened up the tank, looked inside, paid the marina to drain and clean out the tank, and solve the problem.

Next week, same problem.

Pulled all fuel lines, and blew them out into a rag. A dead hornet body had logded in an elbow between tank and filter. Passed enough fuel to run part-throttle, but not full draw.

Got money back from marina.

[picc53]

ok put a new lift pump in and tested it by opening up the bleeder and putting the truck in gear, key to crank postion with tires blocked fuel came up. Then today drove around for over an hour had no problems. then on way back home it started having trouble up a small hill made it home. Tested the lift pump again nothing came out of bleeder don't know what it could be know confused any help. Is the lift pump no good again or is something else wrong it idles and turns on with no problem even when i got back

[JohnC]

Try leaving the fuel cap loose. Sounds like you may be generating a vacuum in the tank. Or maybe the oil pressure switch gives up after an hour or so.

[picc53]

right no we have the lift pump wired independently to a toggle switch that we turn on when we go start the truck it is wired into the fuse box and we grounded it. question for last post what would create the vacuum? ALso the oil pressure switch is bypassed would that have an affect?
about 15 min later or so i checked the pump again and fuel was coming up when i tested the pump

[picc53]

when i had trouble after driving i would press the gas and like nothing would happen then it would go catch then samething but didn't stall

[gmctd]

Possibly the in-tank filter on the pick-up tube - 'the sock' - may be stopped up

[JohnC]

Using fuel from the tank can cause a vacuum if the vent in the cap doesn't work properly.

Be careful; having the fuel pump wired to a switch is a safety hazzard. The pump needs to stop if the engine stops, otherwise it's a potential fire hazzard in the case of a wreck.

[picc53]

the pump does stop when we shut off the truck the vent is in the gas cap so should i just loosen up the cap do you think it could be something else we changed all fuel lines and sending unit about 2 months ago just werid you information is much appreciated let me know if its any way to fix problem

[JohnC]

Try running with the cap loose to see if the problem occurs. If it doesn't, get a new cap. If the cap is off a gas vehicle, get a new cap.

The rule is the pump must stop when the engine stops for any reason (like a severed fuel line), not just when you shut it off.

[picc53]

its seems like the fuel filter container has diesel in it for a certain amount of time then dies out then if i let it sit with the pump on the trucks starts up with no problem. could the injector pump be pulling more fuel? or something else

[gmctd]

Or something else, pic - reread thru the responses from the beginning

[Robyn]

Hi and welcome.
Noticing the posts.
You need to get that fuel system electrical back to proper operation.
Not only does the fuel pump need to stop when you turn the switch off it needs to stop if the engine should be killed in a wreck where the ignition is still switched on.

Good idea to check the fuel lines starting at the tank.
Remove the tank and check the pickup tube as well as any soft lines that hook the tank to the metal lines.
Be sure you dont have any issues all the way to the back side of the pump.

Problems after the pump will usually show up as leaks.
Check the fuel return line from the IP to see if you are getting any air bubbles. (Install a piece of clear tube temporarily to test)

Its got to be either an air leak or a pump issue.
Check the fuel pressure with a gauge at the drain line to see what the pressure is with the engine running.

Needs to be about 5lbs if its really low you have issues.

Hope this helps

[Robyn]

If your truck has dual tanks it can easily be a tank switching valve assembly issue.

Robyn