Comparison Tier IV Questions For Messicks

[DieselBound]

[Response to above post] In regards to emissions stuff, 2005 isn't a concern. I believe my B7800 is a 2008 (I got it used and I've never been able to get it through my head whether a 2008 or a 2006- suffice it to say it's newer than 2005) and it has no emissions bits on it (no cat, no EGR, nothing). Again, there are specified compliance dates.

 

[bilrus61]

Any worries about this are silly. No one should use emmissions as a buying factor. We sell every variation of emmissions and none are any better or more trouble free than any other. 90% of the issues with this stuff are operator induced.

[That is not what the driver of my local Kubota/New Holland dealer said. He was picking up my Kubota 7040 to adjust the reverser cable. He stated they were having lots of issues with the newer Kubotas and the emission stuff but that New Holland tractors were even worse. He said he was always being sent to pick up the New Hollands that were in "limp" mode and some wouldn't even drive up the ramp on his trailer. He was looking for a older Kubota backhoe but said he wouldn't have a newer one with that stuff on it.

Oh and the mechanic at the dealer I talked too said the same thing and he was keeping a eye out for a older Kubota in the 40/50 HP range for his private use. He said he didn't want one with the all the add ons to the engine causing trouble and I was the one left defending the newer Kubotas! He said that in ten years all that stuff was going to start to tear up and everyone was going to be shocked at how much it cost to keep the newer tractors in repair down the road. He said the age of the "30 year" tractor were over. You were either going to buy one and use it up quick with lots of hours on it or just do without and hire your tractor work done in the future.

 

[jeff9366]

My take on it is that the smaller 3 cyl indirect injected motors are able to meet the emissions requirements without the added exhaust treatment. All the chart is really saying is that ' a certain group of HP rated motors ' must meet the requirements at ' said date '. They do not mandate that the motor must have X, Y, or Z on them to meet these requirements at a certain date, they just have to meet them.

During 1998 nonroad engine regulations reducing emissions were structured as a 3-tiered progression. Nonroad regulations use metric units, with regulatory limits expressed in grams of pollutant per kW. Examples of regulated applications include farm tractors, excavators, bulldozers, wheel loaders, backhoe loaders, road graders, diesel lawn tractors, logging equipment, portable generators, skid steer loaders and forklifts.

Each tier involved a phase-in (by engine power) over several years. Tier 1 standards phased-in from 1996 to 2000. Tier 2 standards phased-in from 2001 to 2006. Tier 3 standards phased-in from 2006 to 2008 (Tier 3 standards applied only for engines from 37-560 kW).

Very stringent Tier 4 emission standards, phased-in from 2008 through 2015, require substantial reductions of Particulate Matter above 19 kW power output.

1) A few light tractors with (small) engine displacements from 68 - 77 cubic inches, slightly exceeding 19 kW power output, meet Tier IV emission standards without costly Diesel Particulate Filters. (DPF)

2) Some tractors with engine displacement around 100 cubic inches are governed by the manufacturers to limit power output to less than the 19 kW demarcation. Tractors under 19 kW ( 19 kW = 25.4794-horsepower) are presently exempt from stringent Tier IV emission controls. Sub-19 kW powered tractors are required to meet only Tier II emission standards.

Since full adoption in 2011, very low sulphur diesel fuel has contributed to decreased diesel emissions.

 

[Tennsawdust]

That's the problem with DPF; they need heat to regenerate ("self-cleaning oven cycle"). They ought to give you two filters and a burn-out furnace, so you can just swap 'em out as they do in some industries.

That is exactly it. They ask you to run at higher RPMs to generate enough heat for the filter to burn out, otherwise you will see increased regeneration cycles. Some of the Branson tractors don't do regen. They recommend a certain percentage of your operating hours be at higher RPMs to keep the filter burned out. For those of us used to lugging around on older tractors that can be hard to adjust to.

Higher RPMs do not necessarily mean more wear though. All engines have a designed operating range and they are safe to operate within those limits. You might even cause more wear by lugging the engine. The bearings, tolerances and, most importantly, the oiling system have been tuned to work within the designed RPM range. With modern fuel injection and electronic engine management it is possible to build an engine that is more efficient at 3000 RPM than older engines were at half that. Combined with cleaner fuels this means the oil sees much less contamination and as a result you see less wear. You probably have a good example of that sitting in your driveway today. Today's cars tend to have smaller engines running at higher RPM than in the past, but doing so more efficiently and with longer durability. As long as you are maintaining the cooling system and changing the oil you shouldn't have any problems with engine life. I don't know how Yanmar or Kubota test their engines, but I do know that in the automotive world most companies expect their engines to show no signs of wear at all after 500 hours of wide open throttle. Total durability requirements are several times that.

 

[majorwager]

Tennsawdust,

I can't prove that engine wear occurs at higher RPM's but you have not proven that it doesn't.

I do contest a 2nd point. Oils do not see LESS contamination, IT Is a MYTH as they actually see more which is why special tier 4 oils were developed

BACKGROUND: just because less soot exits the tailpipe, does NOT mean internal combustion is cleaner. THE EGR valves recirculation of DIRTY EXHAUST GAS back through the engine to reburn it is a real concern. Many engineers contend this emissions tool shortens the time span for on road engines w/ cylinder sleeves to require rebuilding.

The emissions criteria has taken us down a road to reduce pollution at the expense of engine health. That may be a lofty goal but it DOES NOT come without a price.


We did NOT design a new engine concept, we took an existing design and modified it to produce a result contrary to the original purpose.
Diesels are designed to be free breathers. They now breath less so humans breath more. That is fine and an intended result of the emissions modifications.

In fairness DO NOT pretend there is NO price being paid. To meet mandated government pollution standards, extended engine life longevity failed to rank as a overwhelming engineering priority. As usual, the buying public will pick up the tab.


EDIT: A further engine comprise is the sulfur reduction, Fuel components, pistons, sleeves, experience greater wear, sulfur was the lubricity factor in fuel. Those that ignore supplements to augment this deleted lubricating agent, do so at their own PERIL.

Tier 4 engines are NOT an enigma. Remove a lubricating factor, fail to replace it, the engine simply operates without said lubricity. Hardly a concern for manufacturers or the government. As long as premature failures are averted, the clock simply expires sooner on the long end. The cost of PROGRESS, Right?

 

[daugen]

My take on this was the higher rpm was usually recommended by manufacturer for a variety of reasons:
1. Meet emissions requirements, which usually requires a "fully hot" engine. Starting a cold engine always was bad news for emissions. Too much unburned fuel.
2. While mowing higher rpm improves blade tip speed which can improve cut when blades aren't kept sharp enough
3. Ensures engine is not "lugged" and that full hydraulic pressure is reached
4. Improves air flow through radiator particularly when filters/vents partially blocked, maintains adequate performance (most important on air cooled engines)

Having said all this, I keep my blades sharp and my screens and radiators air blasted after every use. So I have zero concerns about idling down a liquid cooled diesel to reduce NVH and save fuel. I sure don't drive my car with the foot to the floor; well, maybe off the line upon occasion
There never has been, and never will be an engine I run WOT, regardless of what it is governed at. (generators excepted)
I'd make an exception for a gasoline fire pump, since that's an emergency.
Otherwise I'm usually at 70-90 percent throttle, which gives me full torque and all the power I need. And a much quieter work environment.
If I needed all the horsepower in my tractor, I'd buy a larger tractor.

Talk about three cylinder design is interesting.
I have a 1997 MF with a 27hp 1.4L 3 cylinder Iseki engine. I have a 2011 MF 49hp 2.7L 3 cylinder Simpson(Perkins), the Indian tractor. And a 2013 Kubota with a 57hp 2.4L 4 cylinder.
The first two have a distinct diesel stink. The Iseki hates cold and woe to anyone who doesn't sit on the preheat for a while. While the Indian Massey has the most unbelievable ability to start immediately in all temps without any heating aids whatsoever. You just turn the key and it starts like a warm fuel injected car engine. And it produces almost no smoke, but the smell, you bet. When I run my chipper on the back of the Massey, you can smell it working. The Kubota is odorless though. Once it gets past the puff of smoke when starting, and a bit of clattering despite double preheats, i can walk around the tractor and not smell anything. And it's not Tier 4 final, so it seems like they got rid of the smell one step before...

Do you remember the early Toyota/Asian catalytic converter rotten eggs smell? Can you imagine having to put up with that on our tractors?
Have to admit, not sure I'd buy any tractor with regeneration. I'll wait for electric. The older stuff lasts forever anyway.
but if you want to drive your tractor into town at high speed with adaptive cruise, yeah, better buy a new one. Good luck when the warranty runs out.

I thought my Kubota was Tier 4 interim, but I guess I'm wrong, tier 3B? Which if I read further up is the same spec, that confirms the low odor.

All of this discussion makes one wonder how much effort the EPA put into actual enforcement, testing at the docks, etc.

 

[daugen]

Since I think Jeff's questions have been answered, a little digression:
When Yanmar "high speed" diesels came into the powerboat world, after powering zillions of sailboats for years,
the big iron guys thought they would be nickle rockets.

A 3600rpm diesel? Impossible! Never last!
Lot of mechanic's hats got eaten. They required very stringent and at times onerous maintenance, but they would run for many thousands of hours at that speed.
While I ran my DD 8V71TI's at 2000 rpm with a WOT of 2300 rpm under load and 2500 rpm without load. Many of you probably shifted older trucks that never got over 2000 rpm.
Unless you were winding out a Jimmy...

Much more stringent emission control has come into boat engines, probably only a matter of time before they need DEF, or something.
Can you imagine how much DEF you'd go through on a yacht burning 125 gph?
Not sure if marine emissions are as stringent as Tier 4 final.
Makes you wonder what Tier 5 will be.
Call up the Gov of California and ask him.
Maybe he'll fine himself for all the smoke his state is blanketing the rest of the country with...

 

[majorwager]

A 3600rpm diesel? Impossible! Never last!
Lot of mechanic's hats got eaten. They required very stringent and at times onerous maintenance, but they would run for many thousands of hours at that speed.
While I ran my DD 8V71TI's at 2000 rpm with a WOT of 2300 rpm under load and 2500 rpm without load. Many of you probably shifted older trucks that never got over 2000 rpm.
Unless you were winding out a Jimmy...

Daugen,

Not sure the DD is a fair comparison. The 3 Louisville fords I had were also the 71 series, 671 to be specific, and they were TWO STROKES, so of course they needed to be driven and revved higher. Not relative to the current 4 stroke designs of today. The Jimmy reference is unclear, unless you refer to a 3208 Cat throw away, naturally aspired, 200 hp gutless wonder.
Underpowering a vehicle is no excuse to mercilessly abuse an engine.


As for the Yanmars, we do not really have any empirical data as to how long they actually lasted. I was in the camp that anticipated premature self destruction. Actually passed on a new deere compact for lack of faith.

But as you stated, consuming fuel at an exorbitant rate , doubt the engine durations pegged 3600 rpm's for sustained periods, certainly NOT thousands of hours at that speed...? With those boats, it is NOT about the speed. You know most yachts spend their life affixed to a dock. How would you impress the public if your boat is bobbing on the ocean where it is unlikely to garner the required amount of public gawking. Besides, when at sea, there is the looming danger of spilling the wine. Yea some cigarette boats have yammer's, not counting those.

EDIT. The discussion here is focused upon diesel engines. Please FOCUS: DIESEL!! The post below ignores the fact that egine longevity is the lowest priority, in designing new emissions equipment. The older CAT C-15 engines and the predecessors easily recorded one million miles. Many deere diesels in the 20 and 30 series saw 15,000 hrs w/o a rebuild. The venerable IH DT 466, saw in excess of 12,000 hrs w/o rebuilding. Not to quarrel w/ Tennsawdust, but his agrumant is not suppored by fact. EGR is great for pollution control, Circulating DIRTY exhaust gas back through the engine is NOT. Fuel burning efficiency is a positive step, but high pressure fuel rail technology alone does not meet tailpipe standards. DPF alone fails the test w/o EGR. It is illogical to believe sending soot laden EXHAUST back through the combustion process, to supplant fresh air as per the engine design, that this DIRTY and abrasive air promotes engine health.

There is no data supporting the MYTH that high engine rpm's and engine wear are unrelated. Saying an engine will operate at high rpm's and burn fuel efficiently simply means the engine will TOLERATE a high speed operation. Does NOT disprove that high speed operation excellerates WEAR.

Emission control systems were/ are developed for one purpose and one only. Satisfy government mandates.
If engine longevity suffers long term as a consequence, oh well!! Reread post # 55. The post below never mentions wear. It simply acknowledges an engine will " TOLERATE" the emissions equipment w/o immediately self- destructing. Very reassuring.

 

[Tennsawdust]

With older engine designs there was a considerable amount of overfueling. That led to inefficient combustion and fuel making its way past the rings into the oil. The old fuel grades - both gasoline and diesel - contained a good bit of sulfur. As one engineer at GM explained it to me, over time the sulfur would create low grade acid in the crankcase and reduce the life of the engine. Along with that you had high degradation of the oil because of all the contaminants it picked up due to the inefficient combustion. Efficient engines don't generate the kind of contaminants that engines once saw. Todays automobile engines can easily go 250,000 miles with anything resembling reasonable maintenance. Back in the days of carbureted engines and sulfur laden gasoline most engines were lucky to make it past 75,000 miles without smoking. The emissions systems being used on these Tier IV tractors are based on technology that was developed for road going engines some time ago. EGR systems have been in use since the 1970's and they are pretty well understood. As a matter of fact, Bosch recently announced that they have developed a system for diesel engines that uses EGR and very tight thermal management to provide emissions that will meet even the most stringent standards - all without DEF. It all comes down to how efficiently they can burn the fuel that is fed to the engine. Todays engines have thermal efficiencies that can surpass 40%. That was a pipe dream not too many years ago.

 

[JerryK]

A big thing about bad starting diesels is that it is indirect injected, thus usually needs the glow plug preheat thing even in the summer. Has to crank some before it want to fire. Most of the direct injected tractors I have owned used a grid heater, or nothing. These started fine without the use of any preheating, but usually complained a little when it was cold and let you know that it was not very happy for a minute or so.