Engine/Transmission (1998.5 - 2002) Painful pix - When #5 conrod brearing eats itself

[Schlickenmeyer]

This is like nothing I have ever seen. Had to post these just for the shock value.

Rod and cap way discolored, bearing almost as thin as tinfoil. lots of crap in the oil pan. man. Talk about a bad week.



I hope 3 pix in one post is ok.



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[EricBu12]

how did that happen? How many miles on the truck?

 

[Schlickenmeyer]

That was a 'under the wire' warranty repair (crank, bearings, etc) at like, 99,600. at about 101,500 or so this happened. I know the mechanic, and he is one of the best I know, hands down. I can't say what caused it. made the truck real mad. :{

 

[WyattEarp]

looks like heat damage for sure, lack of oil lubrication? That is sure nasty looking, hope you get it fixed. Curious what type of oil filter do you run?

 

[Schlickenmeyer]

Plenty of oil, 10-30 (Minnesota). Run a Stratopore filter, Keeps it light green for a few thousand miles. Possibly the wrong bearing. . if too tight, it would tear itself up.

 

[jwilliams3]

Maybe a lubrication restriction somewhere?

 

[lmills]

Just curious, but why did the engine need new bearings and a crank at 99,000 miles?

 

[Schlickenmeyer]

The front seal had eroded a slight groove in the crankshaft, and we caught the leak on the last check before the warranty expired.

I do not know enough about how the crank is lubed to say if a restriction could have caused it. I will mention it to my mechanic, thanks!

 

[BILLVO]

The front seal had eroded a slight groove in the crankshaft, and we caught the leak on the last check before the warranty expired.

I do not know enough about how the crank is lubed to say if a restriction could have caused it. I will mention it to my mechanic, thanks!

I have never heard of replacing the crankshaft because of a seal groove there are replacement seals from cummins and many other companys that come with a preassembled wear sleave with them. the pics look a lot like lack of lube The mechanic probably used too much engine assembly lube while assembling it and plugged the crank oil journal in that area. these engines are to be assembled with new clean oil only no engine assembly lube. On cumins larger engines warranted by cummins themselves they would have an oil sample pulled and check for assembly lube and if detected the warranty would be voided. The engine needs to be prelubed before starting them. I have seen this scenario on many of cummins N14 engines.

 

[cerberusiam]

The mechanic probably used too much engine assembly lube while assembling it and plugged the crank oil journal in that area.

Huh???





I will give you the pre-oiling is a good idea and should always be done but the assembly lube story sounds a little suspicious. The lube is made to protect bearing surfaces until the oil pressure comes and I have never seen any of it that will plug an oiling hole at 60psi plus of oil pressure.

 

[Schlickenmeyer]

And the shop manual says oil, so I am sure that is what he used. He is quite good, and a by the book kinda guy.

 

[BILLVO]

The mechanic probably used too much engine assembly lube while assembling it and plugged the crank oil journal in that area.

Huh???





I will give you the pre-oiling is a good idea and should always be done but the assembly lube story sounds a little suspicious. The lube is made to protect bearing surfaces until the oil pressure comes and I have never seen any of it that will plug an oiling hole at 60psi plus of oil pressure.

Its no bs I've seen it happen many times with the lube its thicher than oil and when it is not used lightly it can get in the oil journals and temporarily starve bearings of oil oil has to overcome the lube and has to force it out sometimes this will not happen until heat is generated remebere there is only a few thousanths clearance in bearing to crank. Plus cummins take on the lube is that it attracts fine particles of dirt that will cause bearing scuffing or failure over time.



If a little is good a lot is NOT better in the case of engine assembly lube.



The bearing failure could have happened due to improper bearing alignment in rod or cap also. do you know if he used plastigauge to check the clearances or not while assembling.

 

[Schlickenmeyer]

That is a god question, I will ask him about that.

 

[obert]

I have never heard of replacing the crankshaft because of a seal groove

Most of us in the real world know that, but Ive read on this site many time that DC's fix for the groove is a new crank... ... gee, wonder why a new truck cost 40K



Ditto on the assy. lube fur cummins, the "clean engine oil" seems to be catching in popularuty for engine asemble procedures, or at least from my small point of view.

Also possible there was a machining defect in the oil rifles in the crank. I was taught the practice of blowing air through the rifles, but I found out the hard way on a steel hydraulic tube that just cause air goes through, oil may not, or at least not good enough.