Hey same here, If I'm wrong I'm happy to know. So in your application how is the engine preventing soot? There also has to be a mesh membrane in there for the diesel fuel injected into the exhaust stream to burn off on.
I think a lot of confusion on these things comes from the huge variety of systems out there. There are also some DOC systems in use that don't meet Tier 4 final but would have met intern that can't continue to be produced. I believe in those cases PM was the issue.
I genuinely enjoy this stuff, not trying to throw stones at all.
Thanks for keeping an open mind MessickFarmEqu. We are all better when learning from one another and that is why I love this site. Lord knows I have the most to learn of anyone here! I too value your videos and input and wish more dealers would get involved with the community. (Dave's Tractor comes to mind as well.)
To answer your question above, I would encourage anyone interested in how the Mahindra mCRD system works to look at this link
Introducing our Tier IV "mCRD Technology" | Mahindra, and also to also check out this independent interview and explanation here:
Mahindra mCRD Diesel Technology There's no right or wrong way to implement Tier 4, but this mCRD was the
best way for me. It is Final Tier 4 compliant and is in my opinion a great solution for at least the casual user, and perhaps even hard core farmers tilling, planting, and harvesting fields all day. There are no membranes or filters like in a DPF, only a flow through catalytic converter that is set up to allow for final exhaust gas conversion of noxious gasses as the exhaust stream passes over and through the catalyst coated surfaces in the DOC pod. Since the efficiency of the engine itself is better there is far less "soot" to begin with than a lower pressure system would generate. Now if a guy dropped a shovel full of mud into the exhaust manifold, then there is a possibility that both systems could get plugged I suppose...
From the Tractor.com site -
(Bold Italic words are my highlights)
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"Mahindra's approach to EPA FT4 requirements (mCRD) began with what would turn out to be a $30 million investment. Involved were major design modifications to the crankcase, crankshaft, connecting rod, piston, flywheel, gear train, cylinder head, and manifolds. A Bosch Common Rail Diesel (CRD) system delivering fuel at 23,000 psi is at the heart of controlling Mahindra engine emissions and greatly reduces engine smoke while delivering the added advantage of decreased sound levels. The mCRD system allows for more efficient fuel combustion through multiple injections per cylinder stroke. For engines above 50 horsepower, a waste gate turbocharger is used along with an air-to-air intercooler.
In conjunction with the CRD performance advantages, Mahindra uses an EGR system with a higher rate of recirculation, a DOC and CCV. mCRD ends up being a simpler solution, with only a $600 tool and any laptop being required by dealers to diagnose the system verses the reports we had heard from competing manufacturer dealers of requiring investments of up to $8000 plus additional technician training. And forgoing the DPF route means no excess heat from the DPF blowoff, lesser system complexity, no potential for the DPF to plug up or need replacement, and no requirement for a back pressure sensor."
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Lastly - I love all brands and know that there are pros and cons to each. I wish folks would simply acknowledge and reward companies that try to meet specific groups of customers' needs. Mahindra, Shibarau, John Deere, and many bigger name brands have put out High Pressure Common Rail DOC systems that negate the need for a DPF and the associated regen challenges. Even Kubota has recognized the demand for a simple and easy use system and has put out its own DOC only emissions control engines on some of their larger models last year. Kubota Expands Diesel Engine Line-Up by Adding New Diesel Oxidation Catalyst (DOC) Only Option (19-56kW) | News 2014 | Kubota Global Site Perhaps it was not across the board due to the cost of retooling the engine designs and plants. If their customers don't complain and only buy Orange K-Tractors each and every time then they are completely justified in making that additional profit margin. Good on them for looking out for their internal stake holders. Mahindra is a new kid on the block and decided to offer something more attractive. I bit off on it, so they must be doing something right. Competition and innovation can only help all of our favorite brands do better in the future in my humble opinion. As a dealer I would be all over my distributor and corporate HQ demanding that the products I sold for them were the best of the best with features that compare or beat the brands I did not deal. Would make my sales easier as well.
As alluded to earlier in this thread by a wise man, all of this Tier 4 discussion may be moot soon if/when Tier 5 comes into being. In that case the DPFs or possibly some DEF injection
may be required on all brands just to meet those criteria. This linked article discusses the electric hybrid possibility as well.
Beyond Tier 4 Engine... | New Tractors | Agriculture
Take care everyone!
