Cummins X15 after treatment issues

[JimT]

(05-06-2024 )Envirotec Wrote:  There was some white/beige colored looking material that had same consistency as soot. As soon as you touch it, it turns to a fine powder. Not sure if it’s pieces of filter or particulate matter from within.

Not sure from that photo, but if I had to guess the white stuff is ash. Could be the result of coolant that has been burnt in the engine, but more likely if it is ash it's from engine oil. Some ash will build up slowly as regens occur and soot is burned off, but I believe engine oil is the biggest contributor to ash buildup, especially on the DPF inlet face.

Speaking of quickserve, they have a nice service bulletin regarding DOC/DPF inspection and reuse. Check the Service Bulletins --> Exhaust Systems section on Quickserve for one pertaining to your engines. If you can't find it and you're logged into quickserve, here's a link to the one that goes with my engine. It has some nice color photos along with explanations of each. While newer filters might look a little different and the pass/fail criteria might be different, the basics in that bulletin should be similar enough. Figure 16 shows an example of ash buildup on the DPF inlet face.