Tier 4 Emissons Confusion

[yooperdave]

Are tier 4 emissions exempt for all new tractors 25hp and less?

Some mfrs note no pollution filter is needed, but is stlll tier 4 compliant.

Any clarification of the issue is appreciated.

TIA

Yooper Dave

 

[jeff9366]

YOOPER DAVE

Are new tractors with <25hp Tier IV emissions exempt ?

The demarcation is 19 kW engine power output = 25.4794 horsepower.

While Tier IV exempt, tractors with <25.4794 horsepower comply with relatively loose Tier II emission requirements.



Some mfrs note no pollution filter is needed, but tier 4 compliant.

Most manufactures can meet Tier IV requirements without a Diesel Particulate Fillter with small displacement engines up to about 27 horsepower via engine design and injection timing.

(Diesel off-road emission standards are uniform in developed world.)

Then there is a horsepower gap.

Beginning about thirty-three horsepower most tractors employ Diesel Particulate Filters.
If there is no DPF there is an alternative incendiary technology to burn off very fine particulates (soot) in some way. Sometimes exhaust heat is elevated all the time, sometimes periodically.

Diesel particulates must be burned. THERE IS NO FREE LUNCH.



Diesel off-road engine manufactures have Tier V requirements in hand. I am unaware of time frame for implementation or if Tier V phase in will occur. Tier V may be a decade in the future when tractor battery power may be an alternative.


Clarification of the issue is appreciated.

MORE: https://www.tractorbynet.com/forums...mpact-tractor-diesel-particulate-filters.html



Consider DPF and other soot burning exhaust technology as a sophisticated muffler.
When considering a tractor purchase consider muffler technology toward the end.

When considering a tractor purchase, bare tractor weight first, tractor horsepower second and (narrowly) rear wheel ballast third.

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

 

[MHarryE]

PM standard is grams per kW-hr so a smaller engine at full power will be dirtier in grams per kW-hr but at full power much closer. The 25 and less range Tier 4 standard was effective in 2008 at 0.4. The standard for 75 - 175 was effective 2014 at 0.02. At full power the smaller one emits 7.6 grams per hour and the larger one 2.6 grams per hour. Rationale in 2004 when the standards were set is the smaller ones run fewer hours and usually not at as high load, plus machines are so small the DPF is difficult to package. My Kubota GR2120 lawn tractor and RTV900XT meet Tier 4 and are smelly and smokey, especially at start. My Kubota L6060 and M7-171 at Tier 4 are odor and soot free as far as I know - they are cabbed and so I wouldn’t notice it.