blown head gasket or egr cooler??

Cummins will not release this information...the guys at my shop say it covers the vast majority of the CM871 motors built. When Cummins updated to the CM871 (EGR & DPF) from the CM870 (EGR only) they changed the length of the liner lip which reduced the torsional support of the liner leading to the issue.

I'm smack in the middle and have a "CPL" in the above average failure rate zone. Wrap your head around this one...I have moved less than 10 loads in the last 4yrs with a gross weight UNDER 150,000lbs (68,000kgs), so suffice to say I power load the engine significantly...and yes I have clearly flexed the block, as I have broke the bolts on the EGR cooler along the number 5 hole 3 times, we no longer install them. (See below, that one and the one on the bottom below, as well as the one ahead of it)

Truck is presently in Cummins with the motor strewn across the shop. I was pressurizing the coolant system and we couldn't figure out why as when we tested the pressurizing gases there was no presence of CO (exhaust gases).

Suspecting rocked/shifted/dropped liners they clamped them after pulling the head and measured the liner protrusion...everything measured great. Knowing I'm in the high failure rate zone I had them pull the liners anyway to check for fretting on the liner shelf. NOTHING, PERFECT!

Turned out to be a cracked head on the intake side internally...clearly a manufacturing defect...lucky me, I'm 22,000mi (35,000km) and 6 months over warrantee! Yay me!

So if you can explain how I can flex the block enough to break the EGR cooler bolts off, but not even wiggle the liner when I'm in the 60% failure rate batch and I constantly place huge power demands, I'd love to hear it...

 

lame, could have glider kit with n-14.

 

What does any of this have to do with a glider with an N14 in it?
We are discussing a Cummins problem...we all know your proud as punch of your MBN. If you can't add to the conversation, then show a little intelligence by standing back and observing to add to your knowledge base instead of interrupting with useless diatribe...

 

I have a similar problem and well I decided to delete egr. Deleted egr thinking it was the egr sending coolant through muffler throwing white smoke. It got deleted capped coolant running into egr capped all coolant going into egr cooler. Turned on the truck.... white smoke from stack. Reved it and now coolant can't seep into egr or egr cooler so now it's coming out of the coolant reservoir. The only thing that remains is a head gasket or a cracked head.