[mbalka]

I learned quite a bit from the Cummins guys this past weekend. Not having owned an emissions compliant diesel in the past (last one was a 5.9L ISB), they explained the system to me and recommended I take a look at the videos they have online detailing SCR and Aftertreatment on other engines, but the systems are significantly similar to those on our Titan XD's. Take a look:




Cummins DEF and SCR overview https://youtu.be/p8clK9qSGlk


Cummins aftertreatment introduction https://youtu.be/SAQBbswpB-0


MB

 

[Fordt]

Great info! But this will make one yearn for that day when the warranty is out, the tuner is installed and the DPF delete is performed...then that mileage creeps up and stays steady, and that exhaust gas temp doesn't feel like the surface of the sun.....

 

[mbalka]

Great info! But this will make one yearn for that day when the warranty is out, the tuner is installed and the DPF delete is performed...then that mileage creeps up and stays steady, and that exhaust gas temp doesn't feel like the surface of the sun.....

I wish I could delete...we have mandatory emissions testing in my county here.

MB:angry:

 

[WireNut]

Exhaust gas/manifold temps are crucial to performance also. Any diesel needs to be operated with an exhaust temperature high enough to eliminate wet stacking, or the buildup of un burnt fuel gathering in the exhaust system. My CATs need 650 degree minimum exhaust manifold temp, they like to be 900+ degrees.

 

[mbalka]

Exhaust gas/manifold temps are crucial to performance also. Any diesel needs to be operated with an exhaust temperature high enough to eliminate wet stacking, or the buildup of un burnt fuel gathering in the exhaust system. My CATs need 650 degree minimum exhaust manifold temp, they like to be 900+ degrees.

Yep, that's the reason for the extra hydrocarbon injections into the particulate filter; when normal driving can't get those exhaust temps high enough. Tim Britt said there were several pressure and temp sensors in the system to detect pressure loss across the filters and catalysts to trigger regen.


MB

 

[WireNut]

Caterpillar (Perkins) who now produces off road and marine engines only, (thanks EPA) and VW place their DPFs at the exhaust manifold to take advantage of the hottest temps, eliminating the need for regen, the manifold temps burn the filters clean without additional fuel being injected into the exhaust system. Gotta be a way for someone to figure out how to get that set up to work for over the road diesels.