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Discussion Starter · #1 ·
I’ll start this off by saying I haven’t heard this truck run yet. LLY. Doesn’t prime. I believe there’s air drawing into the fuel system. Previous owner replaced fuel tank, sending unit, fuel lines up until where they turn up at the fire wall under the cab, filter housing and has a cat filter adapter. I noticed there’s a small amount of liquid in the shrader valve/test port above the alternator? The rubber hoses from the filter housing to the ficm looked cracked up but the insides looked good still. An injector return line was popped off and it made the drivers side of the engine wet with fuel till it dropped on the ground. Which leads me to believe that the cp3 is functioning. I’m in the process of replacing those. Guy claims the truck was sitting at idle in his driveway, puffed white smoke out of nowhere and shut off. To never run again. Studded, new head gaskets with 10k miles. Trucks got an intake, lbz mouthpiece, 5 position switch, down pipe and exhaust. 165k. When the gaskets and studs were installed the shop said injector 6 was out of spec, but he drove it with no problems and replaced said fuel system components up until it smoked and shut off. Wanting to pick everybody’s brains, wondering if there’s anything else I could check. I’m trying to avoid installing a lift pump, because I understand that that’s a bandaid for this sortve problem.
 

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Since it's extremely difficult to test and find where air might be leaking in, people usually pressurize (gently, like blowing from a shop vac) the fuel tank and then look for leaks. Oh, or how about a bandaid? IMO, these trucks should have come from the factory with a lift pump. Why screw around with a shop vac and trying to seal with a rag, while then looking for a leak? What if you're taveling? A gentle lift pump (like the one from John Kennedy) is a nice setup and is reportedly good for the CP3 pump.
 

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The rubber hoses from the filter housing to the ficm looked cracked up but the insides looked good still
When it's time to replace the filter head, it's also time to replace the lines running to/fro it. Use 1/2" bulk bio-fuel compatible hose.

Not sure how an 'insides' inspect was done.

Kitty adapters can be a leak source (and a downgrade in filtration). Remove the inlet hose to the filter head, cover the pipe end (thumb), check to see if the primer pulls a vacuum, and holds it for prime.
 

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Discussion Starter · #4 ·
When it's time to replace the filter head, it's also time to replace the lines running to/fro it. Use 1/2" bulk bio-fuel compatible hose.

Not sure how an 'insides' inspect was done.

Kitty adapters can be a leak source (and a downgrade in filtration). Remove the inlet hose to the filter head, cover the pipe end (thumb), check to see if the primer pulls a vacuum, and holds it for prime.
When I removed the outlet hose, it appeared from the inside, at least what I could see, was smooth and crack free. I just replaced both lines, and I pressed the primer button till it got hard, loosened the bleeder screw and it sprayed some air now I’ve got fuel. Charging a battery right now as well.
 
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