Crankcase filter

[rocketman45]

I have searched the forum but have not seen this issue. Due to stop engine light had crankcase filter replaced. Thought all was fine til about 1000 miles later stop light on again.
Diesel mechanic has run code again and high crankcase pressure code again. Pressure is within good limit when filter is out but runs high when filter is in. No other codes, and no obvious mechanical symptoms... oil level ok, no smoke, no leaks, engine runs fine. Cummins 400 ISL. Anyone ever encounter this?

 

[Rich W.]

Never encountered it but its on my to-do list. What year is the coach and what was the milage on the engine when the stop engine light and code(s) appeared and what are the codes? That filter has a maintenance interval of around 75k miles (dont recall exactly). Any signs of derate?

 

[Aa1ssradio]

I was getting the same issue on my 2010. After the second check engine light for high crankcase pressure and second filter change I just ignored the check engine light and just reset it.

 

[rocketman45]

This is a 2009 American coach with 400 ISL. Bottom line in a nutshell Cummins knows about this issue. Basically the system is too airtight. Filter out pressures good. Filter in pressure high causing SEL. leave Filter in take oil cap off pressure fine . I have hours of research and input from several diesel mechanics. This is one of those wonderful EPA things brought by our government. To fix this to government regs would cost more than a new engine. Plus the impossible task of having it recertified by EPA. Cummins actually produced an "empty" Filter they said as a "stop gap" (wink wink) until the problem could be fixed. Some folks have removed all the material from the Filter, Some have replaced the oil cap with an old style breathable one and some other creative things.

 

[rocketman45]

Never encountered it but its on my to-do list. What year is the coach and what was the milage on the engine when the stop engine light and code(s) appeared and what are the codes? That filter has a maintenance interval of around 75k miles (dont recall exactly). Any signs of derate?

The mileage was 40k when it coded. Different opinions on when that filter should be changed. Range from 35 to 100k.

 

[Rich W.]

This is a 2009 American coach with 400 ISL. Bottom line in a nutshell Cummins knows about this issue. Basically the system is too airtight. Filter out pressures good. Filter in pressure high causing SEL. leave Filter in take oil cap off pressure fine . I have hours of research and input from several diesel mechanics. This is one of those wonderful EPA things brought by our government. To fix this to government regs would cost more than a new engine. Plus the impossible task of having it recertified by EPA. Cummins actually produced an "empty" Filter they said as a "stop gap" (wink wink) until the problem could be fixed. Some folks have removed all the material from the Filter, Some have replaced the oil cap with an old style breathable one and some other creative things.

Sounds a lot like the DEF debacle. Be thankful you don’t have to cope with that! Under the circumstances, I’d go with a breathing oil cap with an external filter on it to keep oil residue off everything in the vicinity of the cap and run with no internal filter.

 

[rocketman45]

Yep no DEF and I had exactly same thought as you for the fix

 

[Joe Hogan]

Here is an interesting discussion about high crankcase pressure

 

[rocketman45]

Interesting.
I should give credit where due... I had a licensed/certified Cummins mechanic who spent 5 hours thoroughly check and test and came to the conclusion. It was not me or a shade tree mechanic taking stabs in the dark.

 

[Rich W.]

Well one shade tree anyway…..