Have we been doing it wrong? High rpm's bad when not needed?

[TractorNoob85]

Does a geared tractor put a more constant load on the engine vs an HST?

 

[5030]

All I can say is, I'm sure glad I don't have to deal with any of that.

I will say the only time I see smoke (soot emanate from either of my M9 turbo charged pre 4 diesels) is a little puff on cold start and if I'm working them hard like a full bale chamber or mowing tall hay at a fairly high ground speed. Other than that I se no visible 'particulates', aka: soot and I'd assume your post 4 units exhibit the same characteristics except the particulates get captured in the DPF or in the case of higher power diesels, burned by the oxidation catalyst, aka: DEF.

I will never own a post 4 diesel, ever.

 

[dkmc]

All I can say is, I'm sure glad I don't have to deal with any of that.

I will say the only time I see smoke (soot emanate from either of my M9 turbo charged pre 4 diesels) is a little puff on cold start and if I'm working them hard like a full bale chamber or mowing tall hay at a fairly high ground speed. Other than that I se no visible 'particulates', aka: soot and I'd assume your post 4 units exhibit the same characteristics except the particulates get captured in the DPF or in the case of higher power diesels, burned by the oxidation catalyst, aka: DEF.

I will never own a post 4 diesel, ever.

Ya beat me to it. I am also glad I do not own anything DEF and never probably will.

 

[Beaver Cove Deere]

I purposely bought a used machine to stay away from any exhaust treatments.
I will however tell you straight up that long warm up time idling in the dead of winter showed up as fuel dilution in my engine oil analysis report. I don’t run much below 1500 and mostly around 2000 depending on task.

 

[RickeyVenus]

Hey guys,
According to this video and John Deer, we should not be using high rpm's on our tractors IF it is not needed. Supposedly people saying it is better for the emissions controls or DOC filters etc. have it backwards. Watch part or all of this video, check out what Deer says and let me know your thoughts?

Yeah thats why my soot is at 78% every other day I sat at 1900- 2000 rpm on my 4044r. I dont know that john deere knows how most people use them.

 

[edrobyn]

Does any of this apply to older diesels that don’t have the smog crap on them?

 

[MarkMac]

I have a 25 hp Kioti, with no emissions equipment.

I typically do non-PTO chores at 1500-1600 RPM. That is where the engine makes max torque and the power output is generally all I need.

My only other diesel is a 2018 Ram with intact emissions equipment. It typically sits in the garage 6 days a week and tows a tritoon or a 3-horse trailer on the 7th day, usually 100 miles round trip on the freeway. I just drive it smoothly and set the cruise control a lot. Freeway speed has the truck at 1600-1700 RPM. I’ve never even witnessed a regen. It manages all the emissions stuff silently in the background.

I’d feel cringy keeping my pickup tach redlined with a minimal (or no) load like some folks do to their tractors.

 

[Sprinkler Fitter]

Ya beat me to it. I am also glad I do not own anything DEF and never probably will.

My tractor does not use DEF but does regen

 

[Dunno]

Let me check what the manual for my 1964 Ford 4000 says about this and I’ll get right back to ya’.

 

[Hermio]

Hey guys,
According to this video and John Deer, we should not be using high rpm's on our tractors IF it is not needed. Supposedly people saying it is better for the emissions controls or DOC filters etc. have it backwards. Watch part or all of this video, check out what Deer says and let me know your thoughts?

I don't know about the pollution control, but the engine itself will last longer if you only run it as fast as needed. The only uses that require full throttle are things such as mowing and rototilling. My tractor does not have a DPF, so I don't have to worry about that.

 

[Hermio]

Something to keep in mind is people with hydrostat transmissions need to operate at a higher rpm to maintain proper oil flow to the pumps.

Not sure that is true. They are positive displacement pumps. I never had a problem running the transmission at low rpm.

 

[Hermio]

Does a geared tractor put a more constant load on the engine vs an HST?

No

 

[Zork]

My Branson is gear with no Regen and I do not use it at full rpm unless the power is needed. I certainly idle when shifting.
I have a smaller hydro gasser and do not run full rpm unless needed even on fast forward/reverse and have not had any issues with the hydro in 22 years.

 

[RandyT]

Not sure that is true. They are positive displacement pumps. I never had a problem running the transmission at low rpm.

It is a variable flow pump coupled to a fixed position motor, and the unit get its charge oil from a separate pump. The issue is the charge oil pump has to have enough flow to maintain the loses of the variable pump. If the charge pump can put out enough flow at idle to maintain proper inflow to the hydro pump you are fine. If the system requires 2000 rpm to achieve that then you can have issues with hydro pump cavitation and galling of the pump mating surfaces.

 

[5030]

I purposely bought a used machine to stay away from any exhaust treatments.
I will however tell you straight up that long warm up time idling in the dead of winter showed up as fuel dilution in my engine oil analysis report. I don’t run much below 1500 and mostly around 2000 depending on task.

Fuel dilution in lube oil when analyzed by a competent lab like Blackstone for instance is a sure sign of either worn rings or injector issues, neither of which I have with either of my pre-4 Kubota M9's and why I'd be very hesitant when buying a used machine, especially one with excessive hours on it and / or no supplied with maintenance records. My OS M9, I bought used from a JD dealer of all things, but it came with not only the original owners manual and the shop manual (which I didn't need because I already have one), but it came with dated service records, right down to the brand of lube oil and gearbox oil installed as well, plus all the filters had the change hours painted on them in paint pen, which is something I do as well as it gives me a quick visual reference as to pending service time. In reality I would not be at all hesitant to purchase a post 4 tractor if I required one, which I don't as both my pre 4 tractors run flawlessly but I would wait until the manufacturers work all the bugs out of them and in my case, for the power I require, they would not only be SCR units but DEF injection as well. I believe under EPA mandate, any unit in the excess of 90 stub pto output requires DEF injection as well as Selective Catalytic Reduction (SCR) or what is now present on units above 26 stub (pto) horsepower. Keep in mind that tractors are rated (for emissions compliance with stub (pto) horsepower, not flywheel horsepower. Motor vehicles such as cars or trucks are rated at flywheel output, which is always greater than driveshaft power, usually 10% more. 10% is the rule of thumb used to take into account parasitic loss in the transmission and hydrostats are usually more than 10% as a rule because of the fluid coupling (hydrostatic drive). In my applications, where I require maximum output at times, a hydrostatic transmission won't work, I must have a conventional gearbox. The one thing I don't want is a dry clutch because many times I'm operating in a 'half clutch' situation, consequently I run tractors with wet, multiplate clutches that are basically immune to clutch plate wear from half clutch operation. My goal is to always have tractors with NO dry clutch in the bellhousing and that is exactly what my hydraulic shuttle Kubota's give me.

I can literally 'ride' the clutch pedal all day and not wear the clutch one bit. Not that I do but I could if necessary. Even with a hydrostat, you will have a dry clutch in the bellhousing that will eventually need replacement and that replacement entails splitting the unit. I don't have that issue with the hydraulic shuttle as all that is in the bellhousing is a damper plate connected to the crankshaft output flange and another plate connected to the transmission input shaft via a set of radial coil springs with the sole purpose of dampening the shock load imposed by abrupt directional changes and even those are mitigated by the proportional hydraulic valving that controls the 'lockup' pressure on the wet clutch pack that drives the gearbox and transmits power to the wheels and eventually, the ground. In reality, it's a very well engineered system that operates flawlessly and eliminates the dry clutch entirely and the hydraulic actuator valve on the side of the main gearbox also maintains optimum lockup pressure and it adjustable if required. it does require a special fitting and liquid filled pressure gage to check but I have that and when I check it, it's always within Kubota listed specification for correct lockup pressure, even on my 6000 plus hour machine.

I believe JD also offers a similar setup but they call theirs a 'power shuttle' transmission.

 

[hiddentacocatneddih]

Idk if I have ever regended mine. Mahindra 485 from the late 80s early 90s. Hope I haven't hurt it

 

[Midniteoyl]

Here's my anecdotal experience. When I first received my tractor I did what my dealer, and several others, said and ran the RPMs up to ~1400-1500 and threw on the Linked Pedal so the minimum idle was that 1400-1500 and the throttle controlled it from there. About half the hours where ran in this condition while the other half was at PTO speed mowing fields. Like this, regens where at 50hrs and very short, only a couple of minutes, and usually done while I was mowing anyways.

This spring I was doing a ton of loader/grapple work that required waiting for others and I started idling down, and I hit a regen at ~22hrs. While it still lasted only a few minutes, it was still less than half the normal time.

As an aside, I think the tractor is programed to do regens at 50hrs regardless? This follows my observations.

 

[Skypuppy]

It is a variable flow pump coupled to a fixed position motor, and the unit get its charge oil from a separate pump. The issue is the charge oil pump has to have enough flow to maintain the loses of the variable pump. If the charge pump can put out enough flow at idle to maintain proper inflow to the hydro pump you are fine. If the system requires 2000 rpm to achieve that then you can have issues with hydro pump cavitation and galling of the pump mating surfaces.

Thank the Lord I don't have to worry about that regen <censored.>
However, my BX2660 manual says to keep my rpm's around 3100 or so when mowing the grass (regardless of engine load I assume as the manual doesn't say anything about that.) So, am I doing it wrong and possibly harming my little 3 banger (25 1/2 hp)?

 

[Deertamer]

Hey guys,
According to this video and John Deer, we should not be using high rpm's on our tractors IF it is not needed. Supposedly people saying it is better for the emissions controls or DOC filters etc. have it backwards. Watch part or all of this video, check out what Deer says and let me know your thoughts?

I ran a bunch of generators while in Vietnam. One Cummins powered 100 kw unit had been on a light load of 20 kw and finally had trouble maintaining that load. I procured a load bank and slowly added load. The smoke attracted the fire fighters and they showed up to find my diesel exhaust blowing black smoke. After a few days of adding load the unit could produce power at the maximum load. Yes a diesel engine needs to be kept working with load.

 

[Skypuppy]

Deer, same for my little 6 and 8 kw units.