RPMS Non DPF

Creature Meadow

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I do a lot of tasks that do not require PTO RPMS, like today using loader to rip up roots.

My tractor is a 2012 L4600DT.

With no regen do I really need to run her wide open or even close to it when not needed?

Using loader today ripping up roots ran it at 1500 PTO is closer to 2500 and idle is at 800.

Just seems a waste but no expert on tractors and diesel engines or hydraulics.

Brush hogging I run it at PTO, subsoiling PTO and 4wd, tater plowing PTO.

But just working around the house running garden bedder, disking in garden, moving various things with the loader, cruising around the farm I run it from 1000 to 1500.

Thoughts on what is best in the long haul, no intentions of ever buying another tractor. Want her to last.

With regards to lasting I only use SUDT2 fluids, OEM filters, Lucas Red and Tacky grease and next oil change will be Amsoil Diesel Heavy Duty. I do use Wicks air filters but all others OEM.

Thoughts on what is best.

Thanks,
Jay
 

85Hokie

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The real reason to run it at a higher "rpm" is that :

1st - it is designed to "run" and produce the most "hp" at that rpm

2nd- placing a load on a diesel that is not running at it's "peak" rpm is not good for that diesel, slopper and what not.

3rd - and very important, hydraulic pumps require "X" rpm to produce NOT THE pressure needed, but the VOLUME needed to run those pumps.

4th - and maybe not as important, tip speed on mowers are designed to cut the best at the rated 540 rpm (3 point) and higher at MMM pto.

5th fuel consumption is sometimes better at a higher RPM than a lower one - or so close that it is beneficial to run it a little higher.

check out this chart on a "typical" 902 engine
 

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Creature Meadow

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Thanks 85Hokie for the response, just after reading I headed down to the garden to disk in the corn, pumpkins, beans, and the middles, I cranked her up to 2000 dropped her in low 4 and cut it in.

After that tossed out (3) 5 gallon buckets of wheat to start my dove field for next weekend.

I'll keep your response in mind as I work Katie and keep the RPMS up.

Jay
 

troverman

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Frankly, I disagree with 85Hokie's assessment. Creature Meadow, you actually have it right. Some tasks require full throttle, others do not. Running something like a mower off the PTO shaft usually requires full power. This supplies necessary horsepower to the implement, and also the optimal driveshaft speed to turn the implement's gearbox. Loader work? Lower RPM is fine. You'll find you may need more engine speed to supply the pump with enough power to provide the pressure you need to lift your load. If 85Hokie was correct, tractors simply wouldn't have throttles at all...they would simply run wide open at all times.

You are not harming your engine or hydraulic system in any way by running at a lower RPM. You are reducing noise and fuel consumption. Larger tractors often have an "ePTO" setting which maintains correct PTO speed but at a lower engine RPM to reduce noise and fuel consumption. Clearly, wide open throttle is not considered necessary by the manufacturers.

With a DPF-equipped tractor, the downside to lower RPM work is that the exhaust is not as hot and soot accumulates quicker in the DPF, requiring more frequent regenerations. If any diesel idles for a long time, cylinder wet stacking can occur...but this is fairly unlikely on a tractor.

In short, diesel engines are not so different than gas engines. They explode fuel using compression rather than a spark plug. The rest of the engine design, involving pistons, valves, a camshaft, and a crankshaft are the same. No one would argue that running a gas engine at a lower RPM is a bad thing. Diesel engines are really no different. Conversely, nothing is harmed by running at full throttle, and certainly that is where your best performance is. But rest assured, I've run my tractors at partial throttle for long periods, I've idled them for long periods, and I've run them wide-open. No harm has come to any of them, and I'll continue to do so.
 

majorwager

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Must disagree with 85 Hokie as well.


Engine is designed to tolerate higher RPM's. That is different from designed to operate at those levels.

With a diesel operating within the torque band, it is more productive than the higher hp level. Look at any diesel performance curve graph. Torque levels fall off at higher RPM's.

HST pump demand is relative to tractor desired speed. It is all relative. WOT is NOT required nor is tractor hyd system harmed at lesser output.


There is significant difference between lugging a diesel, operating well below torque band, and operating within the band.

Just saw a post from Messick's. Fuel consumption undeniably higher at higher engine speeds.

Of course, PTO operation should match implement suggested output.
However, my log splitter has a pto pump. I never bother to operate that pto pump at more than 1500 RPM's. just isn't necessary. My BH also has a pto pump. When I operate engine at 540 pto speed controls are jerky. Much smoother at slower speed.

My loader is very responsive on the Kubota. When plowing snow or grading driveway, I operate at 1500 rpm +/-, again more controllable.

Lastly, w/ my finish mower, in light cutting, I dial back the RPM's by a few hundred below engine 540 output, No visible difference in cut and a noticeable difference in fuel economy.

Had HST tractors since the early 90's and gear tractors since late 50's. Operate them in same manner, no major issues, NO DPF however !!


EDIT: Noticed some folks become somewhat sensitive , no defensive, when faced w/ disagreement....

Don't really see a correlation between activities described by Creature Meadow and those on a site work construction project, but 30 years as a G.C., and still learning....
 
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85Hokie

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Guys....

Disagree all you wish, that is why we are here!:D:)

However - you do not see any true machine operators running a diesel engine at idle or half throttle, now true - 99% of the time they are doing "work", but running a diesel AT a low RPM.....is NOT good for a diesel at all. AND that is why those the run heavy equipment do not do it! AND yes, I understand that we are talking SCUTs and CUTs not track loaders.

in this statement:

There is significant difference between lugging a diesel, operating well below torque band, and operating within the band.

If you "hear" an engine lugging.....well, it is like having a idiot light on your chest saying you are having a heart attack....little too late. Many lug it WITHOUT knowing the harm for which they do, and it will not show up until later in the engines life. Many people dont know the difference between in the power band and below.;)

Many of the people who own diesels think THEY are hurting the diesel by running it at or near WOT....and here again.......it is a thinking process that has no basis other than an internal "thought"....

it is true that you will burn MORE fuel at a WOT than at above idle, but as charts show, the curve is a little different in the middle.

I find on my BX25D that I cannot get any work accomplished a 2200 rpms...... and I find that when I hit 3K ....everything works some much better and smoother! On the B7100.....grass cutting is better at or near WOT, even the HST seems to run smoother at that spot.

Bottom line - run them where YOU feel comfortable, and forget the rest:p
 

rkidd

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The real reason to run it at a higher "rpm" is that :

1st - it is designed to "run" and produce the most "hp" at that rpm

2nd- placing a load on a diesel that is not running at it's "peak" rpm is not good for that diesel, slopper and what not.

3rd - and very important, hydraulic pumps require "X" rpm to produce NOT THE pressure needed, but the VOLUME needed to run those pumps.

4th - and maybe not as important, tip speed on mowers are designed to cut the best at the rated 540 rpm (3 point) and higher at MMM pto.

5th fuel consumption is sometimes better at a higher RPM than a lower one - or so close that it is beneficial to run it a little higher.

check out this chart on a "typical" 902 engine
I ran heavy equipment for 38 yrs at a very high level,from D-3 to D-8s, from mini excavators to 110,000 lb excavators, from a Polar crane setting the reactor head on the reactor at a nuclear plant, and virtually any type of heavy equipment made, and 85 Hokie is dead on, on all of his points. Diesel engines are made to run at I always do at least 85% of max rpm for good performance of the engine and the hydraulics as he said. The hydraulics definitely work better in this range on any piece of equipment. As Hokie said, no operators run a backoe, excavator or dozer at less than full throttle for a reason. A good percentage of new heavy equipment only has an electric switch, that is either idle or full throttle. No in between. That is from Caterpillar and other big manufactures that know a little about diesel engines. Running a 2500 rated rpm tractor at 1500 rpm is not running it in its power band. On my B2650 rated for 2500 rpm when not doing 540 pto work, whether it be loader work, or snow plowing, or anything else, the lowest rpm I run is 2100 -2200 rpm. When running my mmm, or a rear pto unit, I run those at PTO speed always. Not saying a home owner type person cant run at lower rpms doing something tricky or something the they are not familiar with until they do get familiar with it.
 
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Fordtech86

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Are y’all talking mostly from an hst side of running rpm?i have a gear tractor,I use the foot throttle control more then anything and rpms always vary,only time it runs at pto speed which is around 2500 rpm on mine is when I’m bush hogging
 

Fordtech86

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I work on diesel trucks and yes I know they love to be run but trucks can’t be run at wot all the time and they last for hundreds of thousand miles,even the city and construction trucks where they spend most the day idling with guys sleeping in them lol,of course the dpf and egr systems don’t like that,maybe that just happens around here lol
 

spacemanspiff

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On a manual transmission, add only the power you need. It won't hurt anything. if it did, I would have broke my tractor a long time ago.

when you are working just hydraulics, such as a backhoe, you will need the pumps at the highest flow to keep things smooth.
 

troverman

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I ran heavy equipment for 38 yrs at a very high level,from D-3 to D-8s, from mini excavators to 110,000 lb excavators, from a Polar crane setting the reactor head on the reactor at a nuclear plant, and virtually any type of heavy equipment made, and 85 Hokie is dead on, on all of his points. Diesel engines are made to run at I always do at least 85% of max rpm for good performance of the engine and the hydraulics as he said. The hydraulics definitely work better in this range on any piece of equipment. As Hokie said, no operators run a backoe, excavator or dozer at less than full throttle for a reason. A good percentage of new heavy equipment only has an electric switch, that is either idle or full throttle. No in between. That is from Caterpillar and other big manufactures that know a little about diesel engines. Running a 2500 rated rpm tractor at 1500 rpm is not running it in its power band. On my B2650 rated for 2500 rpm when not doing 540 pto work, whether it be loader work, or snow plowing, or anything else, the lowest rpm I run is 2100 -2200 rpm. When running my mmm, or a rear pto unit, I run those at PTO speed always. Not saying a home owner type person cant run at lower rpms doing something tricky or something the they are not familiar with until they do get familiar with it.
Let's not twist things - nobody is suggesting 'operating' a tractor at idle or just above idle. The OP was talking about 1500RPM or so. He was also not talking about running the PTO. As I said, most PTO implements are designed to operate at 540RPM...which is just below wide open throttle. Therefore, it is important to run near or at wide open for optimum performance. I'm just suggesting for other tasks it is just fine to run at lesser RPM.

I work on diesel trucks and yes I know they love to be run but trucks can’t be run at wot all the time and they last for hundreds of thousand miles,even the city and construction trucks where they spend most the day idling with guys sleeping in them lol,of course the dpf and egr systems don’t like that,maybe that just happens around here lol
That's just it...all these examples are cited of heavy equipment diesels, but what about on-road diesels? They rarely are running at wide-open, and spend a lot of time idling. Ever seen a Kenworth in a parking lot on a cold night just sitting their idling to keep the driver warm as he sleeps? And even when that same truck is driving down the road, it surely isn't running at wide open. Yet you can get a million miles out of these engines. So clearly you cannot make a generalized statement that it is harmful for diesels to be run less than full throttle. It is not.
 

Creature Meadow

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So it appears a number of differing opinions here which is good and creates discussion.

Reading all the post I did some path let me know if my thinking is correct.

I do than you all for weighing in.

Idle = 800 RPMs = 0%

1200 = 25%
1700 = 50%
2100 = 75%
2500 = 100% 540 PTO

I used 800 as my zero for the calculations since that is where it runs at idle.

So, when just "messing" around the farm no loader work, no ground engagement I'm leaning toward the 75% or 2100 RPMS.

This a good compromise, I was closer to 1500 most of the time which is below 50%?

Thoughts?
 
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I'm with Troverman. When I'm working it, higher rpm's. When it's a fancy wheelbarrow i run around 1500. My 1 ton spins about 12-1300 at 55mph.
 

Creature Meadow

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Are y’all talking mostly from an hst side of running rpm?i have a gear tractor,I use the foot throttle control more then anything and rpms always vary,only time it runs at pto speed which is around 2500 rpm on mine is when I’m bush hogging
Mine is gear as well and I often do the same. I set throttle at about 1500 then use the foot pedal when I'm moving, this way when I let off foot pedal and stop it still keeps RPM's up some.

I use the 10 minute roughly rule if tractor is not in use to run at the 1200 to 1500 range, but longer than 10 minutes I turn off tractor.
 

rkidd

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Let's not twist things - nobody is suggesting 'operating' a tractor at idle or just above idle. The OP was talking about 1500RPM or so. He was also not talking about running the PTO. As I said, most PTO implements are designed to operate at 540RPM...which is just below wide open throttle. Therefore, it is important to run near or at wide open for optimum performance. I'm just suggesting for other tasks it is just fine to run at lesser RPM.



That's just it...all these examples are cited of heavy equipment diesels, but what about on-road diesels? They rarely are running at wide-open, and spend a lot of time idling. Ever seen a Kenworth in a parking lot on a cold night just sitting their idling to keep the driver warm as he sleeps? And even when that same truck is driving down the road, it surely isn't running at wide open. Yet you can get a million miles out of these engines. So clearly you cannot make a generalized statement that it is harmful for diesels to be run less than full throttle. It is not.


Not sure what you are fishing for with this post. You should really sharpen up your reading and comprehension skills. I never twisted anything or suggested that the op wanted to operate at idle or just above. I simply stated the facts that I know.He actually said 1500 rpms which I commented on and used for an example. And if you look at his post, #12, 1500 rpm on a tractor that has a pto speed of 2500 rpm is less than 50% and that is his table. Not optimum at all.
 

rkidd

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Mine is gear as well and I often do the same. I set throttle at about 1500 then use the foot pedal when I'm moving, this way when I let off foot pedal and stop it still keeps RPM's up some.

I use the 10 minute roughly rule if tractor is not in use to run at the 1200 to 1500 range, but longer than 10 minutes I turn off tractor.
Creature Meadow. I also surely agree, that with a gear tractor you can run several hundred rpms lower than an hst tractor. I also like your 10 minute rule. Good luck with everything.
 

Creature Meadow

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Good evening, listening to my Cardinals play the Dodgers on MLB, stay a game behind so I can skip commercials. Tied in he 6th.

Heading to the deer lease tomorrow to disk plots for first time this year. his will make it quicker when we plant the plots in 2 weeks. Then it will only require a light disking before seeding and covering.

Pulling the disk I will run her close to the 540 for about 6 hours tomorrow.

Thanks again for the responses, insight, and your opinions how best to operate the tractor with regards to my question on RPMs.
 

Oliver

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I find this thread interesting because I'm now trying to determine if I'm operating my tractor (B2650) incorrectly or inefficiently. (Full power is at 2,500 rpm)

Mowing I now run it at 2,500, maybe 2,300 in thin, sparse, grass.

Just driving slowly around the fields carrying a bucket of top soil to shovel into ground hog holes I'm in mid range at maybe 1,600-1,800 rpm. Just seems pointless to run at max power to do this.

Scooping up and dumping snow to clear my drive I run about the same 1,600- 1,800, maybe a bit higher, but certainly not over 2,000, when moving slowly and lifting relatively light weight any more power would seem to be wasted.

Should my tractor be at its max rpm for all these tasks? The reason I run at lower rpm is to save fuel and wear. In the case of mowing I started doing it at 1,900-2,000 but found cut quality not very good so after a couple months started running it at 2,500. Cut is much better but it definitely uses more fuel mowing the same area vs when I did at 2,000.

My thinking is running max rpm just to creep around the property or lift light buckets of snow seems overkill, and definitely will use more fuel.
 

Creature Meadow

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I find this thread interesting because I'm now trying to determine if I'm operating my tractor (B2650) incorrectly or inefficiently. (Full power is at 2,500 rpm)

Mowing I now run it at 2,500, maybe 2,300 in thin, sparse, grass.

Just driving slowly around the fields carrying a bucket of top soil to shovel into ground hog holes I'm in mid range at maybe 1,600-1,800 rpm. Just seems pointless to run at max power to do this.

Scooping up and dumping snow to clear my drive I run about the same 1,600- 1,800, maybe a bit higher, but certainly not over 2,000, when moving slowly and lifting relatively light weight any more power would seem to be wasted.

Should my tractor be at its max rpm for all these tasks? The reason I run at lower rpm is to save fuel and wear. In the case of mowing I started doing it at 1,900-2,000 but found cut quality not very good so after a couple months started running it at 2,500. Cut is much better but it definitely uses more fuel mowing the same area vs when I did at 2,000.

My thinking is running max rpm just to creep around the property or lift light buckets of snow seems overkill, and definitely will use more fuel.

I understand and that is why I started the post seeking advice from the experts here.

While hogging or using most ground engaging implements I do run close to 540 or PTO, mine is 2500.

Your concern or questions are the same I had.
 

Creature Meadow

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I think it is important to point out that I am asking about a non dpf, gear drive tractor, tried to make that clear in my OP.

I know little about requirements for operating a DPF tractor and one that is HST, as I have never owned one so what I read is all I know.