Won't start after sitting for 24 hours

[lostintexas]

My M1009 has been in and out of the shop now for hard starts for the past month with a long list of replacements being done but I'm still at the same place. If the truck sits for more than a day it simply will not start. It turns over fast and strong, after replacing batteries and starter. Glow plugs were converted to manual before I got the truck but those have been replaced and they still test good. Temp doesn't seem to make any difference as today was mid 60's and it won't crank and it was in the 30's a few days ago and it fired right up. Each time the shop get it started again by bleeding the air from the lines which tells me a fuel issue or more specifically the fuel is leaking out or back into the tank after time. We've even taken the intake off and tightened the lines. So my question is which tech manual do I need to be reading and what else can it be:
injectors?
Injection pump?
Bad lines?

Any help is much appreciated, getting frustrated as I'm so over budget at this point and still don't have a running truck for more than a few days at a time.

Thanks

 

[doghead]

All rubber fuel lines are suspect.

Your fuel filter base(especially around the pressure sensor) may be suspect.

Your fuel tank sending unit tubes may be rusted outside or inside the tank.

Air can suck in, and fuel may not leak out(all this is under suction).

 

[lostintexas]

Thanks DogHead! Looks like I'll be replacing lines and dropping the tank next.

 

[Bethelfire]

Try parking it facing downhill and see what happens.

 

[lostintexas]

Try parking it facing downhill and see what happens.

Not doubting but what does that show/do? Will give it a try just curious. Thanks.

 

[markg]

Thanks DogHead! Looks like I'll be replacing lines and dropping the tank next.

change or fix the filter base, thats more than likely your problem. thanks. mark

 

[Recovry4x4]

I would do a little search for FM100. This is an upgrade to the filter system. Read up on it and see if it's something you are interested in. The factory filter base is always a little suspect when you have symptoms you describe. As cabeza de perro indicated, all of those are suspect so each will require a little looking into.

 

[lostintexas]

Sorry guys. The truck already had a spin on filter on it before I got the truck and I forgot about that. I will still take a look at it. Thanks again everyone!

 

[dependable]

Also check if lift pump is working well. Just had a lift pump go bad myself.

To check if fuel lines are leaking, and also to backfill & prime new filter, use compressed air with air gun and tube, block fuel fill at tank with rag and apply air pressure. This is a good way to find leaks in system. Leaks will show up in positive air pressure conditions that would not show up with fuel pump vacuum.