So I am on my way home to Oregon from a week long install project in Oklahoma and about 500 miles from home while pulling a hill, we lost some power, started blowing some smoke from the exhaust and had oil all over the front of the block. I have been towing a 10,000lb trailer the entire trip(4,000+miles) and had my power chip set to 80. And also for the entire trip I have not exceeded 1200egt for but a few seconds at a time. So when I finally came to a stop, the engine had a dead miss, and more blowby. There are no engine codes. My first thought was a leaking HPOP hose, but that is not the case. The drivers front of the motor has oil all over it, but no obvious source, and it appears to have been blown all the way back to the turbo. There was more oil then should have been , but not more than a cup or two tops. Even when cleaned off and ran. My wife is coming to my rescue with my AE to help me figure out which cylinder(s) are missing. but for now any ideas? Is it possible that it is only an injector gone south? I did already pull the drivers valve cover and disable injecotrs one at a time, only # 4 was a little questionable, The rest made a significant change in idle. ANd I have to have my truck up and going again in about 11 days.

 

Sounds like you lost a piston, my guess is because a cooling jet fell off a while ago and the piston overheated on that long hard pull.
An easy way to verify the loss of compression is to disable the injection by unpluggin the CPS so it won't start.
Crank the starter. You'll hear the starter "unload" on the weak cylinder. It will freewheel past that one cylinder and then return to the normal cranking sound for the other seven.
I don't think I need to tell you what to do next if that is what is wrong.

 

I feel for you, but look on the bright side: You get a fresh engine out of this deal. One that you'll know every detail and dimension inside of. You already have the right rods.

And one with secured cooling jets.

I just wouldn't want your "time crunch" to get it all done. Hope you have a great machinist to work with.

Pop

 

Doubtful that its a blown cylinder, I would guess a o ring somewhere... Blown piston would not cause leaking oil. And the truck would run REALLY bad... Trust me I know... #7 and I had issues...

 

Okay, I hate reading this kind of stuff because it makes me realize how ignorant I am on these engines. What the heck is a cooling jet??

The good thing is that you all are here to enlighten us s

I consider myself pretty decent with my gassers, but man, I really have a long way to go...

Joe

 

It's a little nozzle mounted in the bottom of the cylinder, has a nearly 180 degree turn on it. It continuously squirts oil on the bottom of the piston crown to help cool it off.
Do a search for an image, I'm sure you'll find one.

 

Under the pistons in an oil galley directional jets direct oil to the bottom of the piston to help cool and lubricate them.

 

Are these unique to our engines or common on diesels in general?

BTW, you guys are quick tonight.

 

It is the thing that is parallel to the connecting rod in the center of the picture.

 

It is common to the PSD, they do tend to fall off for one reason or another, found one once when doing an oil change...LOL

 

How would losing a cooling jet cause oil to be on the outside of the block, on the front?

 

Thats why I doubt it is a piston issue. Sounds like a HPO plug came out from somewhere, low ICP and there you have a dead miss...

 

 

I've read stories in TDR about pieces of foil seals from 1 gal oil jugs finding their way to piston cooling jets and burning pistons on Cummins, at least that was the report after tear downs. After reading that, I began removing the seals myself before having oil changed at Wal-Mart's.

 

Kwik- Yep, I think it's terminal. After letting her cool down for a while, unplugged the engine harness, and she deffinately has a hiccup in her get-along. Has a very obvious loss of compression in a hole. Great, just what I needed. . Now, my question is, since I am still 500 miles from home, will I ruin anything if I unplug the injector to the dead hole and nurse it home on 7 cylinders? The mystery oil I can't reproduce. Maybe caused by a massive increase in crankcase pressure when the piston failed under max load and blew oil out of the valve cover gasket?

Next question is where can I get rebuild stuff, and what should I do that is proven and will help reliability within reason. I am thinking head studs, injectors, Turbo?? or big oil? Man I do not have the time for this