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What would cause excessive blowby? This happened almost overnight.
Everthing was fine until yesterday and the engine is pushing smoke out of the breather.
I changed the cc filter, changed the oil filter ran it for a couple of hours and it went away.

Today its back with a vengeance. Oil pressure, temps are normal, no coolant loss.
No power loss.

My fear is its the head gasket. I was getting a wiff of exhaust out of the fill tube.
Any other ideas?

cracked piston perhaps?

This is what it looks like.

(05-17-2016 )Nilao Wrote: [ -> ]cracked piston perhaps?

Yeah that would do it too....
I guess its my turn for big headaches.

maybe a cylinder cutout test could help pinpoint it?

Could be a broken ring.

Looks like the very same thing, that happened to my cm871.
I dropped the oil pan, and pressured up the coolant system, and found number 4 cylinder with coolant running down inside the liner.
Turned out to be a head gasket
What are the miles on your motor?

(05-17-2016 )in2trux Wrote: [ -> ]This is what it looks like.

I thought mine had to much blow by so I took it to cummins they have a blowby test on the dyno at a reasonable price turn out mine was fine.

The truck is home now, intact. The problem is worse, so at this point the truck is off the road.
With 665k on the engine I'm going to assume it's inframe time....

Anyway you look at it, the head will probably have to come off and patching the problem isn't going to help in the long run.

If it is a cracked piston or ring I don't want to stress it with a cutout test.
One way or another I have to find the source of the problem and fix it right.