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I think yelling at the guy through the keyboard is unproductive. Making some big assumptions without any evidence doesn't help either.
You're making the assumption there is no damage to the bearings. That's a tenuous assumption to make on an someone else's engine. We don't know the entire story, including just
how long it was run without oil. Wasted turbo bearings won't put that much glitter in the oil. It's a darn good bet much of it is from the engine bearings.

Unless he is willing to drop the pan and remove rod caps, nobody knows the facts. However, assuming the engine bearings are 'probably fine' is the wrong
way to err. And suggesting he rod the piss out of it up a steep hill is just plain stupid. You can do what you want to your engine, but it's incredibly irresponsible
to suggest such a course of action to others :rolleyes:
 
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You're making the assumption there is no damage to the bearings. That's a tenuous assumption to make on an someone else's engine. We don't know the entire story, including just
how long it was run without oil. Wasted turbo bearings won't put that much glitter in the oil. It's a darn good bet much of it is from the engine bearings.

Unless he is willing to drop the pan and remove rod caps, nobody knows the facts. However, assuming the engine bearings are 'probably fine' is the wrong
way to err. And suggesting he rod the piss out of it up a steep hill is just plain stupid. You can do what you want to your engine, but it's incredibly irresponsible
to suggest such a course of action to others :rolleyes:
This scenario is something I've seen more times than I can count in the past 20 years of involvement with these engines. It is my experienced opinion responsible troubleshooting is putting the engine under a load to get the oil on the hot side of operating temp and observing two things- bearing noise and oil psi at idle speed. If there's no noise at sub-600 RPM idle speed and oil psi is 15 or better I'd say carry on and run it as hard as you want.

In my opinion it is reckless to suggest inspecting engine bearings on a hunch.

And failed turbo sleeve bearings most definitely put a lot of shiny glitter in the oil. That glitter gets trapped in the oil filter. It won't reach the bearings.

Just stop and logic this through for 30 seconds...

If there was any crank bearing damage whatsoever you would, without question, have some noticeable noise at hot idle.

If there's no noise indication of a problem then there's a pretty good, say 99.99% chance that the bearings are good to go.

Running it hard up a hill to heat the oil system and observe the idle oil PSI is just part of troubleshooting.
 

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This scenario is something I've seen more times than I can count in the past 20 years of involvement with these engines. It is my experienced opinion responsible troubleshooting is putting the engine under a load to get the oil on the hot side of operating temp and observing two things- bearing noise and oil psi at idle speed. If there's no noise at sub-600 RPM idle speed and oil psi is 15 or better I'd say carry on and run it as hard as you want.
That has got to be one of the most ignorant things I've ever read, and considering the amount of ignorance on the Internet, that's quite an accomplishment.

In my opinion it is reckless to suggest inspecting engine bearings on a hunch.
You know what they say about opinions, right?

Unless the pan is crammed up against the crossmember, it doesn't take that much to pull the pan and pop the rod caps off. I can do it in under an hour in my truck, but I do have a removable crossmember.

And failed turbo sleeve bearings most definitely put a lot of shiny glitter in the oil. That glitter gets trapped in the oil filter. It won't reach the bearings.
Depends on whether the bypass is open. If the cold oil pressure spikes,, the filter may bypass. Especially if it has a bunch of crap in the element.

Just stop and logic this through for 30 seconds...
I have. Maybe you should try it?

If there was any crank bearing damage whatsoever you would, without question, have some noticeable noise at hot idle.
Absolutely false.

If there's no noise indication of a problem then there's a pretty good, say 99.99% chance that the bearings are good to go.
Your 99.99% theory is 100% WRONG! My engine had no bottom end noise when I bought it. I checked the rod bearings, even though oil pressure was fine and I had no reason to believe anything was wrong with the bearings. Here's what I found:




Those bearings are shot, but not so bad that they drastically dropped the oil pressure or caused noticeable noise. Even though the copper is exposed, the increase in clearance was minimal.

BTW, that damage was not due to a loss of oil pressure. That is the damage caused by continually lugging the engine. The driver of the vehicle this engine came out of did this damage. He probably listened to all the idiots who don't know crap about diesel engines telling him "Diesel engines LOVE to be lugged!"
. I've seen fools say that same thing on forums more times than I can count as well. Fortunately, the crank journals were still in decent shape, so all that was required was to replace the rod bearings.

The main bearings were in excellent shape:



The excellent condition of the mains is how I know the damage to the rod bearings was due to lugging. Well, that, and information from a major bearing manufacturer showing different types of damage and their causes. My rod bearings looked exactly like their pics of rod bearings damaged from lugging. With the exception of the upper main+thrust bearing, I didn't replace any of the mains. In fact, except for the main+thrust journal, I didn't even remove the caps from any of the other mains. I replaced the upper main+thrust half because the thrust flanges had worked loose from the main shell (they are a simple interlocked and peened attachment), which is relatively common.

Running it hard up a hill to heat the oil system and observe the idle oil PSI is just part of troubleshooting.
Yeah? Tell me, which page of the Cummins service manual instructs you to do that as a troubleshooting procedure? What part of any reputable service manual says that is a legitimate troubleshooting procedure?
 
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Discussion Starter #24
well, the engine is still doing fine and it's daily driven. I'm searching hard for a good 6bt for the swap. I hope it holds up until this fall because I don't think I will do the swap in the heat of the dirty south with no shade to be found. The injection pump isn't tuned for this baby h1c so if I hit the gas then it will bog down before the turbo spools up. I'm actually getting better MPG which I think is due to the h1c turbo only hit 15psi instead of my normal 30 psi from my old hx30w.
 

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well, the engine is still doing fine and it's daily driven. I'm searching hard for a good 6bt for the swap. I hope it holds up until this fall because I don't think I will do the swap in the heat of the dirty south with no shade to be found. The injection pump isn't tuned for this baby h1c so if I hit the gas then it will bog down before the turbo spools up. I'm actually getting better MPG which I think is due to the h1c turbo only hit 15psi instead of my normal 30 psi from my old hx30w.
You know what they say about "hope", right? If you don't want to inspect the bearings, maybe invest a meager $30 in a used oil analysis? Go here to get a free sample kit, complete with free return shipping: Free Test Kits | Blackstone Laboratories

Before you send the sample off, go online and pay for the analysis here: Pay | Blackstone Laboratories

You will get an "Order #" to put on your sample slip so they know the analysis has been pre-paid. That way there are no delays waiting for payments when they get your sample.

When you get the analysis back, post it up here if you want. I'm sure members here will be gad to offer opinions ;)
 
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