Rawze.com: Rawze's ISX Technical Discussion and more
Excessive crankcase pressure? - Printable Version

+- Rawze.com: Rawze's ISX Technical Discussion and more (http://rawze.com/forums)
+-- Forum: Big Truck Technical Discussion... (/forumdisplay.php?fid=1)
+--- Forum: ISX Related Help (/forumdisplay.php?fid=68)
+--- Thread: Excessive crankcase pressure? (/showthread.php?tid=2478)

Pages: 1 2


Excessive crankcase pressure? - dhirocz - 12-11-2017

Got a bunch of stuff done to the truck this weekend. And I was feeling good too!

I had a fairly oily spot underneath and around the breather when I was working on the truck this weekend. I figured it was crankcase vapor blowing back onto the engine. I washed it all off, thinking I'd keep an eye on it.

Today I go to check my trans cooler during my post trip and find it all oily again. At first it looked like it was coming from behind the compressor, but upon closer inspection, it looks almost as if oil is being forced out from under the valve cover and is running down the head, though it seems oilier on the driver's side.

It's already been @m*m^2'ed and it has the new crankcase breather with an extra hole drilled into it. Im cringing here, but it seems like the crankcase is pressurizing because of blowby. At 730k, it might be getting close to that time. It's only been running @m*m^2 now for 45k. Still seems to run fine, however.

Have I overlooked something? I figured it was maybe the front structure, but with oil on the back and sides of the head running down from the valve cover, I would think blowby first...


RE: Excessive crankcase pressure? - hhow55 - 12-11-2017

Could be the turbo seal.


RE: Excessive crankcase pressure? - Signature620 - 12-11-2017

Without seeing photos, it sounds like leaking front cam plate orings. If it's not running out I'd put it off until you get it rebuilt.


RE: Excessive crankcase pressure? - Rawze - 12-11-2017

You could start by switching over to the cummins no-element crank case filter unit if you think it has high blo-by...

http://rawze.com/forums/showthread.php?tid=1051&pid=8950#pid8950

Some pictures of where it is leaky would be nice too.

===

The problem with DE-manding an older engine is that it revels things you never knew. Just think what happens if for so long, you have carbon packing around those rings,.. then suddenly you make the engine burn much cleaner than it did before and all the carbon packing goes away. Sometimes after a while, the engine will settle and blo-by goes back to normal,.. but sometimes it does not go away.

- What ever you do, take steps to ensure you are not getting excess pressure buildup in the crank case. Make sure the engine can breathe well,... very well if need be. As an engine ages, and the blo-by gets higher and things wear out, then someone needs to drive it a little softer up the hills, keep boost down a bit, slow down a bit whenever possible to save fuel and wear, and start focusing on saving up for that inframe.


RE: Excessive crankcase pressure? - dhirocz - 12-11-2017

...already have the new element.

This problem didn't start until the last thousand miles or so ago. Maybe less.

Could be cam seals...doubt it though. I replaced the cams and bearings recently, and the seals were replaced at that time. You never know, dumber things have happened...

I'll upload pics shortly.


RE: Excessive crankcase pressure? - dhirocz - 12-11-2017

Driver front


RE: Excessive crankcase pressure? - dhirocz - 12-11-2017

Passenger front


RE: Excessive crankcase pressure? - dhirocz - 12-11-2017

Passenger rear


RE: Excessive crankcase pressure? - Rawze - 12-11-2017

(12-11-2017 )dhirocz Wrote:  ...already have the new element.

This problem didn't start until the last thousand miles or so ago. Maybe less.

Could be cam seals...doubt it though. I replaced the cams and bearings recently, and the seals were replaced at that time. You never know, dumber things have happened...

I'll upload pics shortly.

MY take on it is when the bearings in the head are shot,... so it the head.

Leakage down the side of the engine cover is something else. make sure the gasket is good and it is torqued properly.