Installing a new fuel filter on a 6.5 and have question

[ghostrider500]

Hello, all.
I put a new fuel filter in the truck today, which was long overdue, and cracked the bleeder valve on top of the FFM with key on and got no fuel coming out. Shut valve, started it up, let it run for awhile, then cracked the valve open with it runnning and it almost immediately died/no fuel coming out of the valve. Finally got it runnning again by keying/turning over the motor.
My lift pump is always making plenty of noise down there, but I don't have a fuel pressure gauge to check its efficiency. (need to get one) But I'm thinking my lift pump is junk. Is this a good assumption?

 

[Will L.]

Likely. The fp will cycle long after the seals that do the pumping are gone. Fuel pressure gauge is about $30. You don't need a high dollar tester.

Disconnect the line going into ffm and check the volume the lift pump can put out. Then just hold thumb over the line and feel if there is any resistance to it. Not accurate, but if you get almost no flow that can clue you in. If you get any decent flow now is a guessing game without a gauge.

Btw a boost gauge will work, just have to spend the time removing and reinstalling.

 

[RI Chevy Silveradoman]

Moved to maintenance section.

 

[Burning oil]

LP could still be good. Jump the relay and crack the bleed, what happens then?

 

[WarWagon]

You could have a plugged tank sock. The IP is stronger than the lift pump and will pull a vacuum that can boil diesel. The lift pump will just make noise.