Fuel pump keeps failing..

[Klingerson]

2 months ago had the fuel pump fail on the M1165. I replaced it with the proper fuel pump, changed fuel filter. There was 1/8-1/4in of sediment in the bottom of the fuel water separator, but the screen was near perfect. When I changed the fuel pump it looked beat up from the push rod and I could depress it easily with my thumb. I fixed this and worked it perfectly.

I drive this truck almost daily and she has more power and no signs of problems, until this morning. It sputtered and surged (no crazy noises) then right as I found a safe place to park, she died. It was low on fuel so I assumed this was the issue. Added some diesel. I bleed the air out of the filter and she started right up, then made terrible noise, loud clanking that's worse with revving the motor. I killed it immediately. My wife gave me a look like $#%@~! Plan B trucks. I'll be taking the fuel pump off this weekend.

I'm a mechanical YouTube idiot, not a mechanic. I'm posting this with anticipation of failure, while its fresh on my mind. Please fill me in on anything I'm overlooking.

Hx on truck: overheated and fan clutch repair 3 months ago, fuel pump, dirty filter.

 

[NDT]

What makes you think the fuel pump made the loud clanging noise?

 

[Mogman]

Video, please.
Maybe you did run out of fuel and now an injector is unhappy.
Not likely a lift pump problem.

 

[Retiredwarhorses]

If your fuel pump failed? The truck would just not start at all…at least that’s my experience in the last 30yrs

 

[Mogman]

Sometimes they sound bad as the air works out of the system, as stated above not a lift pump.
I would give it another try.
Have your phone handy for vids.

 

[frauhansen]

Ohh Dear, that topic follows me me

You sayed at the time you changed your lift pump you had to clean the filter too. And there was water and debree in it.
That let me assume that all this water and debree must be came out of the tank
And now you was running low on fuel, maybe you cleand your tank now into the filter.

Checking the function of the lift pump is (imho) easy.
Crank the engine and open the outlet port of your fuel filter. Or the water drain tap.
The Diesel must be bubbling out of it.
If not, your lift pump is failing again.

When I changed the fuel pump it looked beat up from the push rod and I could depress it easily with my thumb. I fixed this and worked it perfectly.

This may be due to the fact that English is not my native language, but here I do not understand you.
There is nothing that you can quickly press with your thumb for a repair?

 

[Klingerson]

I took the advice and turned it over again, it cranked up and then was 3 min of rough idle. Afterwards started sounding better. It's back on the road.

Thanks for help and encouragement

 

[frauhansen]

Sounds like air in the system. Next time bleed the system by open up a incejtor (19mm wrench) and loosen the injector inlet. When the diesel is flowing out of the open inlet, close it again, Air is gone.

 

[Klingerson]

Sounds like air in the system. Next time bleed the system by open up a incejtor (19mm wrench) and loosen the injector inlet. When the diesel is flowing out of the open inlet, close it again, Air is gone.

Next time I’d only need to do this to one injector?

 

[frauhansen]

I simply chose the injector that was easiest for me to reach. And I think that's cylinder no. 4.
And yes, I only opened one.