Compact Tractor Diesel Particulate Filters (DPF) Version 2.0

[leonz]

It certainly makes me more determined to use a catalyst pellet exhaust gas
purifier when and if I invest in a new or used diesel mule.

I installed a Foley Engine Service catalytic muffler on my commercial firewood
splitter as the fumes from the honda GX340 gas engine always made me sick
before I did that repair work.

 

[jeff9366]

"I like the idea of no DPF on the Mahindra."

Beginning about thirty-three horsepower most tractors have Diesel Particulate Filters.
A few Tier IV compliant tractors between 26 and 75 hp use DOC (Diesel Oxidation Catalyst) conversion. Mahindra is one. Mahindra has DOC of similar construction to DPF. Both the DPF and the DOC are honeycomb ceramic filters which supercede a muffler.
The DOC forces engine exhaust over a honeycomb ceramic structure coated with platinum, palladium, and rhodium. These catalysts oxidize carbon monoxide and hydrocarbons into carbon dioxide and water at hot exhaust temperature.

Mahindra has a DOC oven hot all the time, DPF tractors have an oven hot intermittently.

There is no free lunch.

 

[jeff9366]

Due to the requirement that new tractors over 25-horsepower meet stringent Tier IV emission rules, which necessitated two stages of emission upgrades over older models, new tractors jump from 26-horsepower to about 33-horsepower. There are very few new tractors around 30-horsepower. Primary Tire IV emission reduction occurs within redesigned engines during combustion. DPF is the second stage, incinerating diesel soot accumulated during 40 to 60 engine hours of operation to a few grams of carbon/ash during regeneration, ash then exits the DPF into the atmosphere. Tier IV exhaust is 99% cleaner than Tier III exhaust.

(Via small engine displacement, higher operating revs and careful design, 26-horsepower Kubota B2650 unusually meets Tier IV standards without a Diesel Particulate Filter.)

The cost of DPF and the computer chip which monitors soot accumulation increases Tier IV compliant tractor cost. Computer chip may also control electronic fuel injection.

 

[hkbirdman]

I don't see a problem with my Mahindra 2555 and DOC running "oven hot" all the time. When I am using pallet forks on the loader while in close quarters - I frequently run RPMs at 800. Also - while doing backhoe work or loader work with the bucket or grapple - most of the time I am running at 1400 - 1500 RPM. This is the majority of work that I perform with my tractor and I cannot remember when I ran over 2000 RPM in performing these tasks. I have to believe that if I had a DPF equipped tractor and ran at these RPMs - I would be looking at more regenerations. In addition - I'm quite sure that I am saving fuel - although I have not calculated for this. At current time I have 375 hrs. and no problems at all.

 

[jeff9366]

I don't see a problem with my Mahindra 2555 and DOC running "oven hot" all the time. At current time I have 375 hrs. and no problems at all.

Neither do I.

I am neutral on emission control system technology; whatever works.

However, there are numerous reports on T-B-N of Mahindra sales personnel telling tractor shoppers that Mahindra tractors do not have a DPF and do not regenerate, both true, implying Mahindra is Tier IV compliant without emission control components. Not true, of coarse. DOC and DPF are pretty similar hardware. From my reading, seconded by multi-line tractor vender Messick's Equipment, tractor emission systems are about equally service prone with operator error responsible for more dealer visits than any other cause.

I purchased my Kubota L3560 in January 2013. Now 1,492 engine hours on the clock. No DPF problems at all.

 

[jeff9366]

I'm joe average homeowner with 10 acres.

Mahindra has no DPF but Deere does and I'd like to avoid DPF due to stories of replacing the unit in 5 years for $1500-2000. [/U]

I am neutral on emission control system technology; whatever works.

However, there are numerous reports on T-B-N of Mahindra sales personnel telling tractor shoppers that Mahindra tractors do not have a DPF and do not regenerate, both true; implying Mahindra is Tier IV compliant without emission control components. Not true, of coarse.

Beginning about thirty-three horsepower most tractors have Diesel Particulate Filters.
A few Tier IV compliant tractors between 26 and 75 hp use DOC (Diesel Oxidation Catalyst) conversion. Mahindra is one. Mahindra DOC is of similar construction to DPF. Both DPF and DOC are honeycomb ceramic filters which supersede the muffler. The DOC forces engine exhaust over a honeycomb ceramic structure coated with platinum, palladium, and rhodium. These catalysts oxidize carbon monoxide and hydrocarbons into carbon dioxide and water at hot exhaust temperature.

Mahindra has a DOC oven hot all the time, DPF tractors have an oven hot intermittently.

There is no free lunch.

The average residential tractor operates sixty engine hours per year, according to industry surveys.

3,000 hours DPF Life / 60 hours = 50 years of residential use prior to DPF replacement.

Diesel Particulate Filter supersedes tractor muffler.
At some point in time DPF needs to be replaced.
At some point in time tractors with mufflers need the muffler replaced.
At some point in time DOC needs to be replaced.

Tire wear and tire replacement will cause as many headaches and more expense than DPF/DOC for most long term compact tractor owners who read and comprehend their Operator's Manual.

For a commercial farmer operating tractor engine 300 to 400 hours per year DPF/DOC will require replacement more often than once in fifty years.

 

[Milo]

If one wished to "do away with" either of these systems on their tractor it seems like it would be easier to eliminate the DOC. Simply replace it with a different muffler or section of exhaust pipe. Am I wrong?

 

[deserteagle71]

If one wished to "do away with" either of these systems on their tractor it seems like it would be easier to eliminate the DOC. Simply replace it with a different muffler or section of exhaust pipe. Am I wrong?

Not that simple. Unless someone makes a "tuner" to fool the tractor's electronic "brain", the tractor won't run. Plenty of tuners are available for diesel pickups but as far as I know, no one has made a tuner for a tractor that would allow it to run without the DPF.

 

[ptsg]

If one wished to "do away with" either of these systems on their tractor it seems like it would be easier to eliminate the DOC. Simply replace it with a different muffler or section of exhaust pipe. Am I wrong?

It does work like that on Branson tractors.

You can either gut the DOC and leave it there. Or replace the DOC with just a muffler and take the computer right off. The engine has nothing linked to the computer nor it will flash any lights on the dash.

There is member here that did replace the DOC with a muffler.

https://www.tractorbynet.com/forums/century-branson/409434-exhaust-mod-my-3725-a.html

 

[Slowpoke Slim]

It does work like that on Branson tractors.

You can either gut the DOC and leave it there. Or replace the DOC with just a muffler and take the computer right off. The engine has nothing linked to the computer nor it will flash any lights on the dash.

There is member here that did replace the DOC with a muffler.

https://www.tractorbynet.com/forums/century-branson/409434-exhaust-mod-my-3725-a.html

Yup, and still performs great 7 months later. Zero issues or negative consequences to doing this mod. Glad I did it. Can answer questions if anyone has them. The Branson DOC system is a "bolt on" add on to an existing tractor, that is sold internationally. So the "bolt on" parts are only added to tractors that are destined for the US, and our nutty/stupid emissions regs.

Works perfectly fine with out the DOC.

 

[jeff9366]

Beginning about thirty-three horsepower most tractors have Diesel Particulate Filters.
A few Tier IV compliant tractors between 26 and 75 hp use DOC (Diesel Oxidation Catalyst) conversion. Mahindra is one. Mahindra has DOC of similar construction to DPF. Both DPF and DOC are honeycomb ceramic filters which supercede a muffler.
The DOC forces engine exhaust over a honeycomb ceramic structure coated with platinum, palladium, and rhodium. These catalysts oxidize carbon monoxide and hydrocarbons into carbon dioxide and water at hot exhaust temperature.

Mahindra has a DOC oven hot all the time, DPF tractors have an oven hot intermittently. There is no free lunch.

Diesel DOC emits dirty exhaust until hot, which would not be allowed in USA road vehicles. Or possibly Mahindra evaluated the $30 billion (and counting) costs incurred by VW for falsifying diesel emission tests and decided its truck technology is not clean enough for export.

BY NOVA3930:

Trying to reconcile all this with what I know about diesel combustion and on road emissions from my various Cummins engines.

Tractor designs only utilizing a DPF, the engineers have probably decided to run relatively rich mixtures and/or are running LOTS of exhaust gas re-circulation (EGR). Those factors reduce combustion temperatures, reducing both NOX and CO at the expense of soot production, which they then clean up with the DPF.

A design utilizing a DOC without DPF is probably running a relatively lean mixture with less EGR, reducing soot and hydrocarbon emissions at the expense of CO and NOX, the CO being cleaned up by the DOC. In the case of the Mahindra with the common rail direct injection, they're probably using multiple injection events to control the combustion process and thus emissions. As I understand their system it's roughly equivalent to an on road truck of the early to mid 2000s vintange. The 03-07 5.9L cummins was a common rail direct injection system with EGR and DOC.

The thing I"m seeing that I guess allows for just using a DOC or DPF and not both is that Tier IV has a combined standard for NOX and hydrocarbons instead of being separate values as in on road requirements. It gives a lot more flexibility in meeting the standards.

I'd also hesitate in directly comparing a DOC with a DPF in their operation. A DOC operates effectively at 300*C+ when a typical diesel EGT is in the 700-800*C range, with bursts over 1000*C. A DOC will operate all day every day just by operating the engine, they don't require any extra fuel.

A DPF in comparison typically requires 900*C just to start consuming soot and requires much higher to consume soot faster than it's produced. That's why they have regen cycles at all. Diesel is injected late in the exhaust stroke where it combusts in the exhaust effectively, driving up the temp to burn the soot. Even then the things still plug up eventually.

Given my experience with on road engines, I'd take a common rail direct injection engine with a DOC over a DPF equipped vehicle all day every day. DPFs are the most problematic emissions component on modern on road diesels. On top of that I wouldn't want a DPF without SCR to allow combustion parameters that minimize soot production to start with.

That's just my general view of the various methods, I don't have any experience with the Mahindra system. All my experience comes from the on road world.

 

[RalphVa]

Gone are the days when as a Benz diesel owner, you could discourage a tailgater by flooring the accelerator. You didn't accelerate away from him as much as you hid him in a black cloud of diesel smoke and particulates.

Yeah, the air is cleaner.

Ralph

 

[nova3930]

Nevermind, think I was redundant

 

[buickanddeere]

Emission Standards: USA: Nonroad Diesel Engines

 

[jeff9366]

VIDEO: Worksaver Electric Grapple for your Tractor - YouTube

Interesting. Seems a bit slow for my liking. I believe that electrical linear actuators will become more prevalent in many applications going forward. To me, the ideal applications are for things such as snowblower chute left/right up/down functions where hydraulics are overkill to say the least.

Europe is legislating to prohibit sales of new fossil fueled tractors, vehicles and other equipment, led by Germany and Norway.

I speculate the first battery powered subcompact tractors will be on the market during 2026. Diesel subcompact tractors have lower power requirements, generally operate close to home so charge can be by electric car charging technology. Existing subcompact tractors have no emission controls, so spew a lot of pollutants for engine power output.

I speculate first stage will be subcompact tractors to 2,000 pounds bare weight, second stage compact tractors to 3,000 pounds bare weight, such as the sooty Kubota "loophole" L2501 and L2501 clones in other brands, with Tier V emission controls mandatory on tractors over 3,000 pounds bare weight.

Electric grapple is one mark of transition to electric power for light tractors.

 

[jeff9366]

rademamj1

The DPF % fill is calculated by the computer, based on in incoming exhaust pressure versus the outgoing exhaust pressure at the DPF. The differential pressure across the DPF measures the blockage on the ceramic filter screens, also called percentage of DPF fill.

 

[jeff9366]

Like the fuel economy of my diesel now.

I cannot comment specifically on your JD 4300 tractor but bear in mind the changes that Tier IV brought to diesel engines to make them burn 99% cleaner also made them more efficient and increased horsepower 2-horsepower to 4-horsepower over predecessor Tier II and Tier III engines. Even factoring in stationary regeneration, I expect most Tier IV compliant tractors have improved fuel economy over predecessor Tier II/III models.

The DPF only deals with the small fuel particulates still expelled by the 99% cleaner engines.

My Kubota regenerates routinely every 60 engine hours in warm Florida. 60 engine hours = 3,600 engine minutes.
Stationary regeneration, which is about 60% of my regenerations because I work in the woods, takes consistently 16 minutes in warm Florida.

16 / 3,600 = .0044 = .44% engine time used in stationary regeneration. (Less than 1/2 of 1%)

 

[jeff9366]

Tier 4 stuff scares me to death, i've never used a machine with it and i've read the stories, it seems some are great and some are just problems. I'm also looking at a massey 2604- apparently it uses a DOC instead of a DPF, apparently it doesn't regen. The farmers around here won't part with pre-emission control equipment.

Tier IV emission standards require tractor manufacturers to add or revise pollution reduction technology on new tractors generating over 19 kW power = 25.4794 horsepower. Tier IV began phasing in during 2009, retail conversion was almost complete in 2013 when I bought my 'Tier IV' Kubota L3560.

Diesel Particulate Filter (DPF) captures exhaust particulates (soot) in a ceramic matrix. When tractor engine runs sufficiently hot, accumulated particulates burn off periodically without operator intervention. If engine is not run continuously hot long enough to burn off particulates, diesel soot accumulates in the matrix. Once heavy soot accumulates in DPF the tractor forces soot clearance with the tractor parked and throttle open to about 2,200 rpm for about sixteen minutes, which makes the DPF REALLY HOT to burn off all accumulated soot. Burning off accumulated soot, either during operation or parked is called REGENERATION.

My Kubota regenerates routinely every 60 engine hours in warm Florida. 60 engine hours = 3,600 engine minutes.
Stationary regeneration, which is about 60% of my regenerations because I work in the woods, takes consistently 16 minutes in warm Florida.

16 / 3,600 = .0044 = .44% engine time used in stationary regeneration. (Less than 1/2 of 1%)


DPF is used by the majority of tractor manufactures on >25.4794-horsepower models, but not all.

A few Tier IV compliant tractors between 26 and 75 horsepower use DOC (Diesel Oxidation Catalyst) conversion. DOC is of similar construction to DPF. Both DPF and DOC are honeycomb ceramic filters which supersede the muffler. The DOC forces engine exhaust over a honeycomb ceramic structure coated with platinum, palladium, and rhodium. These catalysts oxidize carbon monoxide and hydrocarbons into carbon dioxide and water at hot exhaust temperature.

DOC equipped tractors have an oven hot all the time, DPF tractors have an oven hot intermittently.

DPF and DOC supersede the tractor muffler.
At some point in time tractors with mufflers need the muffler replaced.
At some point in time DPF needs to be replaced.
At some point in time DOC needs to be replaced.

There is no free lunch.


Tire wear and tire replacement will cause as many headaches and more expense than DPF/DOC for most long term compact tractor owners who read and comprehend their tractor's Operator's Manual.

 

[Milo]

I assume emission requirements will further tighten, does anyone know when tier V is coming and what it will entail?

 

[nova3930]

I assume emission requirements will further tighten, does anyone know when tier V is coming and what it will entail?

The general EPA push is to "near zero" emissions across the board so don't be surprised to see a tightening of both particulate, SOX and NOX standards. Give it another 10-15 years and I expect basically every diesel engine made will be fitted with DPF, DOC and SCR systems.