Was combing through previous posts and there was a statement about the plastic supply and return line 'O' rings failing. Having replaced the lift pump several times now I CAN see how at least that connector could be bad. However, I had a friend squirt a considerable amount of air into the tank using rag to hold the air while I looked for fuel leaks - didn't see any. But then I did not focus on that connection either.
Have any of you figured out a replacement for those push on fittings?

Just a little reminder - this is not simply our primary vehicle - it's our only vehicle and we really need it particularly this time of year.

Thanks for all the feed back. Sure would have been an expensive bummer to have replaced the injectors and IP only to discover they were not the problem!! At least I feel like we are closing in on it.
Ron

 

That is a problem. It may not be the only problem. but that negative pressure will exaggerate any air leak you may have in the lines or pump. The pressure needs to equalize somehow. sounds like it's happening through your fuel system instead of the cap.
Try your next test with the fuel cap loose.

 

You can hear air swosh from my fuel cap aswell when just about empty but runs just fine. So I doubt thats your problem but loosen it just to check just sayin.... Sounds like sucking air somewhere to me also.

 

Put 4-5psi into the fuel tank and check out the fuel lines.

 

Is the shut down soliond still gutted,if you are sucking air it will run rough when you start it with eather.If shut down is not gutted try that .

 

Honestly, I can't see how the engine runs any more than a minute or so if it is pulling a vacuum on the tank.

I had a vent on my Ford to get plugged and it would not run more than a mile on that tank before the engine shut-down.

Of course, the plastic tanks on these trucks may be just sucking together like a big bladder.

If I had a fuel tank that seemed to have vacuum on it whenever I loosened the cap, I would make a BIG vent in the tank's top even if I had to cut a new one with a hole-saw.

 

The solinoid is all back together. My tank is about 1/3 full. I 'tested' the tank cap by sucking on the vent and it was allowing air through fine, I could hear the little one way valve opening and closing so I think the cap is ok after all. Didn't taste very good though

I am suspecting that perhaps the supply line from tank to lift pump - the slip on connector may be the culprit.
Can anyone tell me if the line I can try to replace that with is standar 1/4" rubber fuel line? I have the chance to have some brought in by bush plane on Wednesday but don't want to order the wrong stuff. It's not just a matter of driving down to the parts store to replace it for me!

 

Ron
Start here the only thing a diesel needs is fuel air and compression
With the engine cold, pull a injector, hook it up to line spin motor. Are you getting fuel ? If Yes

Check valves.

 

Plug it in, it is old.

 

I can do the injector / valve check, but I adjusted them not quite 10,000 miles ago.
When the engine did run it spun clear to 2400+ rpm with no hesitation - not trying to be contrary, but wouldn't that indicate the valve adjustment is in at least fair shape??

Also, this problem manifisted itself in a way that don't seem to indicate slowly deminishing performance like you might see whith valves slowly going out of adjustment.
But then I'm no expert -

 

Do your grid heaters work?

 

Ron
call if you like

608 576 1sixthree three us cell
or I could call u

 

Hey!
I'm old and I don't have to be plugged in yet!

Yes, the grids are working.

Really wondering about the correct diameter fuel line though - seen a few posts in past articles that mention a fix by replacing the hard plastic lines from the tank with rubber fuel lines. This also is supposed to illiminate the push on connectors at the lift pump and return line whoe's O rings may be old and allowing air to enter the system.
I have replaced 3 lift pumps in the 18 years I have owned this truck so am guessing that at least the connector on the lift pump could be the leak point. Been thinking about Running the truck for a few minutes, then gooping the slip on connector with some heavy grease and seeing if it will start in an hour or so. Just not sure any amount of grease simply applied to the connection externally would stop it from sucking air.

 

I'm no expert ether but process of elimination dont cost $

NOTE dont use EITHER any more.. use Propane

 

PS: that would be gooping up the slip on connector Before I start and run the truck and then try letting it sit for a while before attempting a re-start.