Cam lobe flaking

I would be trying to get Cummins to help. We lost a motor in a 2013 KW last year with 350k miles due to a bad fuel pump plunger. Bill was $47k. Cummins covered all but $18k but took 8 weeks to get it fixed.

If you are the original purchaser they MAY hep you out?

There is a waranty guy from Cummins on this forum that may be able to hep you out?

 

@Belials

 

With all the research I have done I believe MINE was caused by trash in the oil galy coming lose and getting stuck in the followers roller bearing. This caused the roller not to rotate for short period of time and started what you see.

The flaking I think is a bad coating on the cam but this has been disputed many times. It crossed over so many years you would think it could have been fixed over the 17 it 18 years of production? Another theory is that the valve spring rate is to high for the mechanical operation.

Cummins will tell you poor maintenance I'm sure? They are supposed to go 500k to 700k between valve adjustments. Mine will get the cover taken off every 100k now. Mechanics will tell you on the side to adjust every year.

 

It was due to poor oil flow design in rockers. There's a TSB about it, was just reading it last week I'll have to fingers it again. They don't come out and say "poor design" but the TSB says "NEW and IMPROVED oil flow". I still have yet to see it happen on the exhaust rocker, it's always intake in my dealings with it.

And that air in vs air out is up for debate. -If you can't get fresh air in then the engine has no air to ignite fuel with.
-Raw fuel out exhaust
-Raw fuel destroys turbos
-Raw fuel gums up EGR cooler and valve
-Raw fuel wipes out DOC
-Raw fuel cracks DPF
-More than likely if you let it persist it will wipe engine anyways so the debate centers around would you rather lose the engine or the engine and the aftertreatment system.

 

With 367k miles there's no warranty unless there was an extended warranty purchased. If you have an extended warranty - get it in a Cummins dealership to be checked out, or enjoy your next bill.

If you don't have an extended warranty - get it fixed now, or enjoy your next bill.

 

Yea not good either way I agree %100!!! I was just playing worst case out loud.

That interesting that you only find intakes bad? Are the valve springs the same for intake and exhaust?

 

Yes they are identical. The TSB and camshaft reuse guidelines calls it "galling"(first sign metal is missing) which eventually turns into macrospaling (really bad). In the definition for galling it actually says "metal transferring from roller to camshaft" which eventually causes the flaking. If you look at all the intake rockers on camshafts that are caught early you can see the signs of it starting on the rollers but not distressing the camshaft yet. I actually have one in the shop right now awaiting customer approval where #4 is bad but the rest of the intake rollers meet reuse but you can see the early signs of a problem. I'll take pictures and post them up once I get approval and start tear down.

 

I do know there is a TSB that if you have to replace the cam you need to replace all the followers and jakes according to Cummins. The new cam is of a diffrent design and needs rockers to match (wider?). Hence the reason I just replaced the complete engine. The repair could have easily got in to $15k I'm sure and who knows how long in a shop?

I would like to see those pictures.

 

This is probly the best description I have heard or read regarding this problem. Makes the most since to me. Thank you for passing this along.

 

mine is not a cummins but a mack, but i just had my cam done new rockers lifters ect and it was a bit over 13k total invoice was 13.7k but i had new windshields put in at the same time so call it 13.5 9k just in parts, if my engine didn't only have 260k on a inframe i probably would have done the replacement engine as well. for the mack i think it was around 14k for a 3/4 replacement engine then if you put in new injectors and a turbo at the time the engine was installed you would get a 3 year 300k mile. but that bill would have ended up well north of 20k all done, everything else looked great inside the engine and now we replaced everything that was re-used at the time of the in frame and everything else still looked great. i still get a 1 year parts and labor guarantee on the cam ect that was just done. inframe warranty has expired based on time sense it was done.