Knocking After Installing Rebuilt Injection Pump

[joeberg]

A friend of mine is having a HMMWV problem that I am hoping someone here might be able to help with. While I can get most things done with minimal guidance, I am far from a diesel expert. I will describe the behavior and what we have done and include before and after videos. The injection pump advance piston was frozen on his 1043 so we replaced his with an IP that we had rebuilt by a rebuild shop (pulled from a Turbo). It was running fairly smoothly before, but we got a deal on the rebuild and figured it wasn't a bad idea. After replacing it, his engine is knocking very loudly and seems to be running faster than normal.If I give it fuel, it smooths out a lot, let off and it goes back to knocking. If I put it into drive or reverse, it continues to knock, but if I put it back into Park, the knocking goes away although it continues to idle a little high. Shut if off and start it back up in park and its back to knocking again.

My first suspicion was timing. We adjusted the timing all over the place and it didn't make any difference at all. My second was that maybe trash got into a fuel line and had clogged an injector. We cracked 5 out of 8 injectors that we were able to get to easily and no difference was noticed. I checked the cold advance and it was basically not even connected due to a broken wire, but it was like that before we switched it and it is mid 90s here, so i don't think that would have any effect anyway but it was reconnected with no change. Also, we let it idle up to temperature and it never goes away. Someone suggested I replace the lift pump, but I haven't done that yet and we didn't have an issue with it previously.
We are at the point where we are ready to switch the IP back to the original, but I wanted to see if anyone had any other suggestions before I go that route. The before and after videos are below. I can't figure out how to embed both videos, so the second is a link. Thanks in advance for any suggestions.

BEFORE:

AFTER:
https://youtu.be/rYu2T3ee740

 

[TOBASH]

Your second video with the AFTER sounds did not post

 

[joeberg]

Fixed the video. Thanks for the heads up TOBASH.

 

[TOBASH]

You already bled each injector.

Have you played with the fuel flow adjustment?

 

[joeberg]

If you mean inside the IP itself, then no. It was rebuilt and adjusted by a professional shop and is supposed to be correct. Is there another adjustment beside that one?

 

[Milcommoguy]

Hard for me to tell the difference on the video. U get all the three bolts in at the pump drive? One not sticking out or ?? Any chance two of the lines got crossed at the pump? Hard to do BUT but but...

I guess one could while it's running crack one at a time injector to determine which cylinder is a knocking. If still knocking, crack some more.

Hard of hearing and out of guesses, CAMO

 

[Retiredwarhorses]

I replace a pump about every 2 weeks in the shop...every now and again, I get a truck that just fights me at every step.
last week was one of those times...the truck in question got a new pump and after getting it started had an injector knock.
i knew which one because it was the one I used to bleed the system....it can take so time to get all the air out, just crack an injection line at the injector and reapply torque, may have to do one at a time.

 

[joeberg]

Thanks. I couldn't crack 3 of them as it was turning the entire injector and I couldn't get to the base with a second wrench. I will bring more tools and try to do that on Monday. It does seem like an injector knock to me. I was concerned trash had gotten in there, but air is more likely.