Engine/Transmission (1994 - 1998) Blown engine?

[THess]

My dad has a 97 2500 5 speed that he has owned since new. It has 200,000 miles on it and has always ran great. Today he was pulling our dump trailer and the oil light came on and he said it started knocking like a gas motor with no oil. He shut it down and I pulled him home. What should be the first things I look for?

 

[THess]

I checked the oil for water and there was none. The radiator was pretty low.

 

[Bob4x4]

If it started knocking it's already too late. Disable the fuel cutoff so it won't start,install a oil pressure gauge and see if you have any pressure while cranking

 

[THess]

Would there be pressure while cranking? It usually takes a while after startup for the pressure to build. Also where would I put the gauge; on top of the oil filter? Where would I find the fuel cutoff? Sorry for so many questions, but we want to have an idea of the problem before taking the truck somewhere. If the engine is toast would you go to a Cummins place or buy a reman and have a mechanic put it in? Thanks

 

[hsmith]

What is the oil level?

 

[BigPapa]

Yes, it will develope oil pressure while cranking. It may take a few seconds, 20-30.



Unplug the shut-off solenoid, that will keep it from starting.



Yes, the 1/8" plug above the oil filter is where I would put a mechanical gauge.

 

[THess]

The oil level is just above add. I talked to a guy at cummins of Charlotte and he said the first thing he would do at his shop would be to cut apart the oil filter and look for metal fragments. I did that but didn't see any fragments only kind of a sludge on the media. I'm going to check that with a magnet to see if it is metal.

 

[HBarlow]

I am not a mechanic but perhaps largely for that reason I would tow it to a Cummins dealer or perhaps a trusted and competent local mechanic and have a Cummins remanufactured engine with a warranty installed.

 

[Bob4x4]

On another note if you cook a piston/score a cylinder from high

Egt's many will mistake it for a rod knock

 

[hsmith]

Agreed. And still with oil pressure.

 

[Missouri Mule]

Oil pump mite be toast.

 

[mweiman]

Is it possible for a timing case bolt or the dowel pin to get into the oil pump drive gear, or possibly an oil pump bolt fall out? I've never heard of it and don't think it would give a very loud knock but it's a thought.

Matt

 

[THess]

Missouri Mule; the oil pump is kind of what I've been leaning towards, but I have very limited knowledge of the engine internals. I talked to my Dad about it yesterday again and he said it was still running when he shut it down. I'm not sure if I've posted this yet or not, but the oil filter was only about half full. Every time in the past at oil change the oil runs out the top of the filter. His truck doesn't have an egt gauge but is completely stock so I never thought it neede one. Thanks a lot for all the replies and suggestions. We aren't in any huge hurry to fix this truck because we now have the 01 for a work truck.

 

[hsmith]

Oil pump failure is pretty rare for sure. Keep us posted please on what you find.

 

[THess]

We had a chance to get an oil pressure gauge hooked up. I disconnected the fuel and cranked but couldn't see any pressure so we hooked the fuel back up and started it. The oil pressure came up immediately and the truck sounded great at idle. When the temperature came up I throttled up a little, and that's when I first heard the tapping. It has a really faint tapping noise; not really a knock at all, but a light tap. Any ideas?

 

[HBarlow]

Try disabling one injector at a time. If it silences the tap you have a piston or rod bearing issue. Very unlikely though.

Also check cold valve clearances. An adjuster could have loosened.

An injector can make a mild tapping noise itself.

 

[THess]

Update

We took the truck to a local diesel mechanic. He found a blown head gasket and said the engine was fine from the top. He did find the head was warped so he had that fixed however he didn't think that these things would cause the tapping noise. The mechanic wants to drop the oil pan and look at the bottom end of the motor. Anybody have any new ideas?

 

[HBarlow]

My idea is that your "local diesel mechanic" may not be much of a diesel mechanic and may be running up a labor bill at your expense.

You did not previously mention coolant loss or obvious signs of coolant leakage. If the engine was not losing coolant it didn't have a blown head gasket and he had no reason to replace it.

He should not need to drop the oil pan to diagnose a tapping noise. A skilled diesel mechanic would disable each injector in turn and listen for the tapping sound to be silenced to identify a bad piston, loose wrist pin, or worn connecting rod bearing. Dropping the pan will not give him any information unless he plans to begin removing main bearing and rod caps. That would scare me.

I would be concerned about the shop and mechanic you have chosen. If you are correctly understanding and reporting what he is doing I would have doubts about his knowledge and skill.

 

[THess]

In post #2 I said the radiator was pretty low so I don't doubt the head gasket was blown. This guy would not have been my first choice, but we live in a very rural area so not much selection. I definitely do trust his integrity though, and weould be totally shocked for him just to run his labor up. Maybe I'm naive, I don't know.

 

[HBarlow]

The man may have integrity but the way an experienced and knowledgeable Cummins diesel tech would diagnose a tapping would be to kill each injector individually, not pull the pan. He sounds like a gas engine mechanic.