Cummins X15 after treatment issues

[Envirotec]

(05-06-2024 )Envirotec Wrote:  

(05-06-2024 )JimT Wrote:  Also, DON'T blow out the DOC/DPF/SCR cans with shop air! It damages the filters. They are not just straight through passages. Blowing shop air through them can cause blowouts in the narrow passages and turns used to collect the soot. Basically rendering them useless.

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.

[hookliftpete]

Could be from coolant seepage into the aftertreatment

[JimT]

(05-06-2024 )Envirotec Wrote:  Unfortunately the answer to every question is NEVER!

In regards to fuel pump, I am looking for someone to test if the pump is actually bad and maybe repair? From what I’ve been told, these newer pumps can’t be tested??

As for the fuel pump, the problem parts are mostly in the pump head. Look up the details on cummins quickserve, but it's 4 bolts to remove the pump head and a few banjo fitting fuel lines. Visually inspect the cam inside the pump body looking for signs of wear, pitting, damage, etc... same as the engine cam. Again, quickserve has steps to checking the pump head for proper function once removed. Basically your checking to make sure the rollers and tappets are not damaged or worn, and the plungers are not stuck. There's detailed instructions on quickserve for testing the plungers and check valve with shop air. It's all pretty simple, anyone can do it. I did mine in a parking lot. Just need a bench vise to hold the pump head in place. Based on years of feedback from owners and shops it's considered a good preventive measure to replace the rollers, tappets and plungers every 400,000 mi or so. When they fail metal debris usually gets sent into the engine oil. I think the newer trucks have a different oil circuit so it doesn't go through the engine before getting to the filter, but still not something you want to have fail on you if possible. There is a gasket between the pump body and head and there are sealing washers on the banjo fittings. I think they are considered single use by cummins but if they are still in good shape (the rubber seal on them isn't chewed up) you can usually reuse them. I usually have replacements on hand for any sealing washers on the fuel system before I open part of it up since you never know what it will look like until you get it off.

[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.

[Envirotec]

(05-06-2024 )JimT Wrote:  

(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.

Much appreciated Jim!

[Rawze]

(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.

EVERY OTHER PASSAGE IN THAT DPF FILTER IS SUPPOSED TO BE BLOCKED AT THE BACK END!!!.

looking at that photo ... you may have very well damaged the holy h#ell out of that DPF filter and ruined it.


The white stuffs is likely ash.. but beige stuffs ARE PLUGS THAT ALSO CONTAIN THE PRECIOUS METALS needed for conversion and proper regeneration!!!!

How the DPF works, is that every other passage thru the element IS PLUGGED AT ITS BACK-END!!!.. ON PURPOSE!.. TO HELP CATCH THE SOOT PROPERLY.. and those plugs are beige in color and change to a darker reddish-beige as the dpf gets older.



If you blow the plugs out by using high pressure shop air like a fool ... then the DPF will get weaker and weaker, the more plugs that get blown out ... and it will NOT regen properly. You will have nothing but regen problems!!!. - IT RUINS THE DPF UNIT if shop air is used that contains any moisture (all liquids are the enemy of a DOC/DPF), or if it is blown out too aggressively and high air pressures!!!!.

Air is used as part of the cleaning process professionally after baking the unit at extreme temperatures and turning everything to ash, but it has to be absolutely dry air.. and it also has to be at lower pressures and higher volumes as to not blow out the cell plugs at the end(s). Professional DPF cleaning machines also usually employ the use of air pressure at both ends simultaneously, to reduce the differential pressures at the plugs, so they do not get blown out.

THE ONLY WAY TO 100% PROPERLY CLEAN THE DOC/DPF UNITS TO THEIR FORMER GLORY IS TO TAKE THEM OFF THE VEHICLE.. TAKE THEM TO THE OEM AND HAVE THEM PROFESSIONALLY BAKED, DE-ASHED, AND FLOW TESTED for a few hundred bucks > on proper machinery designed for this!!!.

!!!... ANYTHING ELSE AND YOU ARE WASTING YOUR TIME AND CAUSING HARM TO THEM!!!.

so .. sure enough.. when I saw that picture when I got up this morning ... all I could do is cringe! and shake my head!.

and said to myself ... WHAT A SHAME!.

Also.. there are countless you#tu#be videos all over the place with BAD INFORMATION, where people wash them out, or use liquid products on them, which washes out precious metals too.. and weakens them exponentially each time they do so.

Liquids of any kind are the direct enemy of DOC and DPF elements!. That or they will blow them out with high pressure air improperly, and do all kinds of ABSOLUTELY HORRIBLE things to them. This all in the name of sheer ignorance and blind dam$n stupidity!. The interwebs is full of this kind of bad information and complete garbage!.

Here is a video that shows how DOC/DPF cleaning should be done ....
info: http://rawze.com/forums/showthread.php?t...5#pid50975

[Envirotec]

(05-07-2024 )Rawze Wrote:  ...
Here is a video that shows how DOC/DPF cleaning should be done ....
info: http://rawze.com/forums/showthread.php?t...5#pid50975

Side note we do not have doser injectors. Not sure how different the newer X15s are compared to the ISX's from 10 years ago. Also, I hope filter is not damaged. I do remeber seeing every other hole plugged even after I blew it out. I did it to two trucks. One had the beige ash and the other did not.

[Envirotec]

These are some photos from truck 24. This DOC and DPF are 6-8 months old.

[Rawze]

(05-07-2024 )Envirotec Wrote:  

(05-07-2024 )Rawze Wrote:  ...
Here is a video that shows how DOC/DPF cleaning should be done ....
info: http://rawze.com/forums/showthread.php?t...5#pid50975

Side note we do not have doser injectors. Not sure how different the newer X15s are compared to the ISX's from 10 years ago.
...

you are correct that many of the newer x15's do not not have a dedicated Doser injector ... because the fuel is instead dumped directly into the exhaust system by way of the injectors in the cylinders during an exhaust stroke. This method of dumping fuel in the exhaust directly is referred to as 'In Cylinder Dosing'.

MEANING IT IS STILL THE SAME REGENERATION PROCESS as other older engines with DPF filters .. using fuel in the exhaust system to raise the temperatures and do a burn-off.

Also... if you did not know this... the vehicvles regeneration system will only ever clean those cans about 5% or so at best. It is not capable at all of making the filters100% clean again.. it does not matter how many times you do a forced or parked regen. The cans need to be removed and professionally cleaned by the OEM every few years at most if you want them to stay healthy long term.

This means that by the time the regen lights are plaguing the truck, .. its far too late, and engine + its emissions systems have been neglected for far too long. Meaning that everything in the EGR systems on the engine is past due for tune-up work to reduce excessive soot production, + now having to remove and have professionally cleaned, the DPF/DOC etc. - It all has to come apart and be cleaned out, serviced, + the cans baked-out, software maintenance done to go with it, etc.etc.etc.

.. and as a fleet owner, or small fleet owner ... ALL of this tune-up work + bake, etc.. should be done every year on each truck, on a schedule, to prevent down time .. BEFORE ALL THE LIGHTS START TO PLAGUE THEM!!!.

HOW DO YOU THINK the mega-fleets deal with it?... they have their own in-house mechanics that service all these things annually for each truck, to prevent any of this unnecessary emissions systems down time that can mostly be prevented when things are done right.

This is the world of modern trucking ... where preventative maintenance is a MUST AND HAS TO BE DONE on a schedule to prevent all the headaches you are now facing ... and you + your mechanic SHOULD BE TRAINED AS SUCH TO KEEP AFTER IT!. Otherwise, waiting until all of it plagues you and the CEL lights are on with endless complaints is the worst, and most costly decision you can make!.


Owning a truck should NEVER EVER be about waiting until the check engine light comes on.. it should be about preventative care (the stuff beyond a damn oil change), first and foremost. .. yet everyone seems to have forgotten how to do this until its far too late\ ... then blame it all on the equipment.

Being VERY pro-active with the emissions and EGR systems maintenance on a regular schedule is the most profitable thing you can do with modern equipment. Anything less and its nothing but endless headaches.

There are also things that can help though too ... like having programming set to be more lenient, to remove most of the derates and shut-downs, without eliminating anything, so that when one does act up, you can at least get it back back to your own shop, instead of having to tow it to a stealers$it that is going to do nothing but throw expensive parts at it. The only down side to this is that an abusive driver may drive it against an actually clogged up DPF for many weeks at a time, .. eventually tearing up the engine.