EGR ?

[Ryno]

Has anyone ever tried keeping the EGR and rerouting so it uses clean air instead of exhaust? on a 2250, 2350

[marek4792]

Cat tried that on their SDP engines using post dpf exhaust, was very problematic for them dusted many engines due to cracked piping.

[tree98]

(03-13-2025 )marek4792 Wrote:  Cat tried that on their SDP engines using post dpf exhaust, was very problematic for them dusted many engines due to cracked piping.

I really think that idea was given up on to quickly. It makes a lot of sense to use EGR gas that isn't filled with soot.

[Ryno]

I was thinking of letting it use clean filtered air then it can control cylinder temps vs a full demandate

[mikkhh]

Ideas is good, but what about the pressure before turbo VS pressure after DPF?

https://www.ms-motorservice.com/int/en/t...irculation

Merc is using low pressure egr, stepped bowl steel pistons on their latest OM654 and 656 passenger car/van engines.

https://group.mercedes-benz.com/innovati...m-654.html
https://group.mercedes-benz.com/innovati...656-2.html

And there are like 100 page long texts about them if you search:
introduction of the inline engine generation OM654 / OM656

BUT what makes me surprised is that WHY crankshafts are missing some of those counterweights? I can not think of any good reason why besides minuscule efficiency gains, but with the tradeoff or reduced reliability and curved crankshafts. The same counterweight optimization story is evident on 2010+ era cars (BMW N47 N57, B47, B57) AND even on some commercial engines - for example Ford Ecotorq.

https://www.researchgate.net/publication...ne_ECOTORQ

On Ford the 8 counterweights on inline6 crank started on year 2004.

https://www.fordotosan.com.tr/en/operati...ine-family
Even the latest ecotorq engines have same style crankshaft and that egr cooler is nicely hidden to make regular cleaning even harder.

For some reason that official website has taken down those introduction videos, but if search for Ford ecotorq Euro6 Ford trucks then there is lots of videos to find.

[tree98]

(03-13-2025 )Ryno Wrote:  I was thinking of letting it use clean filtered air then it can control cylinder temps vs a full demandate

I don't think your understanding how this system works. The clean air is coming in from the turbo, EGR gas is pushed through to the intake from the exhaust manifold by turbo backpressure and metered by the egr valve. There is no way to push "clean air" through the EGR circuit on a Cummins ISX, nor would you want or need to. Essentially all you would be adding is boost and thats not a good idea. The ECM can control cylinder temps on its own just as long as it has GOOD PROGRAMMING.

[Rawze]

(03-13-2025 )Ryno Wrote:  Has anyone ever tried keeping the EGR and rerouting so it uses clean air instead of exhaust? on a 2250, 2350

This is as much of a violation as de-mandating it, itself. The laws protect the components and the design, prevention of ANY TYPE of alterations whatsoever ... and it has nothing to do with not what actually comes out of the tail pipe.

Next, like other have said.. unless you put a blower to force it back the other way thru separate piping at higher pressures than the intake.. then it will never reach it. I suppose someone could pump it into the intake of the turbo.. but then it would also require some serious CAC cooling system to get it back down to ambient temps before it reached it too. It would also require additional filtration or the turbine of the turbo and would get eaten up due to SCR crystals and other nasties over time as well.

If someone wants to keep all the emissions systems intact.. SIMPLY DO EGR TUNE-UPS ONCE A YEAR AND BE THOUROUGH ABOUT IT!!!.. replacing dirty sensors, cleaning piping, taking cans off every 250k miles to have them professionally cleaned, etc.etc.etc.. AND DO PROPER REGULAR SERVICE ... and problem is solved. - There are plenty of people who do this and run their engines a million+ without a lot of headaches. It is everyone else, who ignores everything until its far too late, who are the ones who have nothing but issues.