Lower End Noise

[jlwelding]

This post is for a friend who is having a knocking noise coming from mid section of eng. I say mid because it really does not sound like the lower end like you would hear on a gas motor, thats how I am compairing it because thats what I am used to. And never heard a diesel lower end knock just because they are so bullet proof.He was pulling a load up a slite hill and it started missing then blew out black smoke then started knocking so he pulled over and shut it off, towed it in. Still had good oil pressure when he shut it off So we cleaned up a set of old injectors I had and put it back together and the miss is gone but still has knock. This truck is stock but for bhaf and exhaust, well it had a old Blue Chip box on it but that was a long while back. And it has 300k on it, SO motor.I think about it and it makes no sence, good oil pressure. Unless he broke a piston

[Mopar1973Man]

Two thing I would do.1. Pull all 6 injectors and have them pop tested. Just to double check.2. Do a compression test to check the health of the cylinders.

[MnTom]

He was pulling a load up a slite hill and it started missing then blew out black smoke then started knocking so he pulled over and shut it off, towed it in. Still had good oil pressure when he shut it off So we cleaned up a set of old injectors I had and put it back together and the miss is gone but still has knock. This truck is stock but for bhaf and exhaust, well it had a old Blue Chip box on it but that was a long while back. And it has 300k on it, SO motor.

I think about it and it makes no sence, good oil pressure. Unless he broke a piston

Sounds to me like a partial melt down. That does happen with even stock trucks! He may have also had one injector not spraying properly and that would cause the same thing too. It will run for quite a while like that, but eventually........ You can run a compression check or just go ahead and pull the head to see what happened. Keep us informed!

[CUMMINSDIESELPWR]

partial melt down is my thought as well, one injector crapped out, dumped fuel, got a piston crown hot and goobered it up. now that piston is unhappy