X 15 565 black oily residue

[2328996abltd]

I got an x15 9000 hrs deleted at 140000km.
It’s has been on and off. Putting a black oily fluid coming from back side of turbo . Also coming out from the manifold where it joins together. It runs ok. Doesn’t go through coolant maybe a little bit once every few months. Doesn’t use any oil. Only does this when is cold especially if I idle it during cold nights -35 or more. No check engine lights or anything. Had valve set done. Any idea as to what it could be.

[Rawze]

could be turbo.. could be valve guide seals.. could be seeping egr cooler, could be a lot of things.

Also.. if it is de-mandated.. assume the program is bad and harmful to the engine internally until you get it properly reviewed.

Copy the program out of the ecm and e-mail it to me for a proper review to ensure you did not just trade away DPF problems with severely shortened engine life... all while swearing that it seems to run ok.

[Colter]

Is the residue hard and tar like?

There's been a pile of issues up here in the cold (below -30c) with wet exhaust, raw fuel in the exhaust, brown/black tar like residue dripping from clamps and down stacks. If so, it's fuel residue, combination of bad fuel and/or low idle/cold engines not warm enough to burn the heavy ends in the fuel eventually causing valves to stick open and get slapped usually on start up.

X15 operating manual states idling engine above 1200rpm when below -18, which is in direct contradiction to their April 2022 (I think) TSB of idle at 900 due to high idle causing raw fuel build up in aftertreatment and melting output module.

De-mandate (cold intake air) with low or negative intake pressure depending on who did the mapping and low idle has been the common denominator in addition to more fuel problems then I've ever seen one winter

[2328996abltd]

Yes tar like and oily. But not engine oil or coolant. Only happens if I run it all night on high idle. Tried a bunch of different rpm settings. Doesn’t happen all the time just on very cold evenings.

[Colter]

It will be fuel, there will most likely be a programing issue that's causing it especially if it happening at high idle as well. It might be fueling unnecessarily to heat aftertreatment which would cause the issue Cummins is trying to alleviate with their new idle recommendations.

It may also have other contributing factors in the programming as well as mechanical issues due to handicaps in the ECM, malfunctioning sensors feeding valid but incorrect information, charge air leaks, dirty intake, restricted exhaust, etc. All things that should be checked prior/during any modifications. There could be layers to the issue and other items that are currently hiding.

I would recommend pulling the current file and having it reviewed. If you need assistance with that there's load of threads on it or ask away.

[2328996abltd]

Ok I’ll look into it thanks