Excessive soot buildup in maxxforce engines

Ok. From what I understood, the smaller displacement models weren’t as prone to failures as the MF13. There was a long list of fixes Navistar did to correct much of the problem. You might run the VINs with a dealer and make sure all the campaigns have been completed. The problem with MF was the high amount of EGR gasses. All you can do is make sure the valves are adjusted and run an oil bypass filter to cut down on soot as much as you can.

 

The oil drains stay the same just the tube that runs from the air cleaner duct to the CCOS is changed it vents to atmosphere from CCOS and the kit comes
With new inlet duct that does not have the provision for the connection between the 2

 

DOC could be on it's way out. Generally you have slightly lower DPF outlet temps. With higher outlet temps this means that DPF is not "baking" down the collected soot, but actually "burning" it inside the DPF itself. This is one sign the DOC is not able to fully oxidize the dosed fuel to create heat and some fuel is getting to the DPF and burning there instead. When you do a regen and you get some white/grey smoke during temp increase, this is another sign of a degraded DOC. You can sometimes prolong its life a bit more by removing and doing a bake and clean along with replacing the doser injector.

 

If your DPF Inlet should be higher than the outlet that is one way of determining a failed DOC, but I have replaced DOC and Regen and still have temps, on DT only, 13L seem to be straight up with the Regen temps. Those are still acceptable but just barely outlet isn’t suppose to be more than 20* higher, so that’s not enough really to condemn it but since you have a fault code for catalyst I probably would say it’s not working efficiently. And your DOC inlet temps being that high also indicate DOC failure it should start reacting at about 500 and wont start sowing until it sees a 200* difference across the DOC so the engine will keep raising heat on the DOC inlet looking for that difference

 

If you’ve had clogged cooler, I would recommend removing the egr valve to be sure it isn’t coked to the point of being stuck! Seen so many of these with this issue.
Removing the egr is the easiest way to see the condition inside the engine. It is the first place to look (mechanically) when the engine health is in question. Pulling the egr will show if you have a coking or coolant loss issue.
They can be difficult to remove without the proper tools. Try this one...

cheap and works well.

 

Dumps the ccv waste products to ambient air instead of back into the intake right infront of the low pressure turbo. I just purchased the 90 intake elbow and then got a 1 inch heater hose and zip tied it to ambient air. elements the by product coking the turbo with oil.

 

Got really off the cuff question.....what are they running for fuel? In the industry i work in we see alot of DOC/DPF issues because they run BIO fuels and do alot of idling. The combined leads to very low DOC temps and regens nearly never happen and if they do are not usually done correctly because the DOC cant get up to temp even with over fueling......

Just a different angle on this......