Cummins N14 Oil in air system

Intake restricted for air compressor
Oil drain in compressor mount restricted
lack of coolant flow, compressors are over heating
compressor over-use
Junk rebuilds.

Are you sure this is new oil, or old still from the original failure?

 

The wrong air dryer will cause that compressor to pass oil. That's a Holset E type compressor & requires a specific dryer for correct installation. A bendix AD9 drop in or Wabco 1200e dryer will work with that compressor. If there is no air dryer installed you need to install a econ valve into the air system. What typically happens is someone replaces the air dryer with a model other than what the truck was built with & causes this problem. I've seen this a few times. Some more info here. http://cbsparts.ca/admin/bulletins/CUMMINS HOLSET E or QE Air Dryer Guide.pdf

 

nevermind posting before coffee

 

We've gone through this with a truck and I ended up working on it myself after $8000 of shop time, I first replaced the air dryer with the right one as mentioned in this quote and the problem went away. Total cost was $320.

 

Not all N14s have the Holeset compressor. My ‘99 has a Wabco compressor and dryer. Since his is a ‘99 also, I’m thinking his may be supposed to have the same style?

Either way, the correct dryer for the compressor is a must.

 

I’ve put two rebuilt compressors on my truck in the 3 years I’ve owned it. Not passing oil, they just get slow to build air.

I’ve never had a Holeset compressor so I don’t know much about them as far as problems.