For what most of us do with our tractors most of the wear on the engines is going to come from starting. The 10k and up between overhauls engines on tractors come when you start them up and run them for 12 hours or so before you shut them down. I run mine where I want to run it. There are diesels that run way more hours than that but they typically run on reefer units irrigation pumps and stuff that run long hours at a time at low rpms.
proper operating RPM
- Thread starter ad356
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I’m with BEEX too, those of you with diesel trucks, do you run them WOT all the time? I don’t. Do semis run WOT all the time? Do they not sit and idle for hours on end at rest stops while driver is sleeping? Only issue being with extended idling on newer engines with all the emission controls is running into more issues with dpf and egr issues due to lower exhaust temps. As far as using your tractor I would use the rpm you need to get the job done efficiently without lugging. I don’t know that my tractor has ever seen WOT. It runs at pto speed when mowing and that’s about it. Even at pto speed when running into a thick patch with the bush hog it’s had plenty of reserve to keep rpms there.
rkidd
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B2650, FEL With QA 60"mmm, 3pt FDR1672,homemade ballast box, BB 1572 box scraper
Bruce said it perfectly....but I'll add to it
I'll tell you this - you cannot run it too high, Kubota DESIGNED it to run at "X" rpm. That is not just a random rpm range that the throttle stops on. So what many are saying when running the machine lower than they "need to" is that they know MORE about the engine design and hydraulic pump specifications than the engineers that creating them.
If you look at most diesel operated pieces of equipment, like compressors, welders, or generators ....they run at "X" rpm, there is no "lowers" setting. Why - because that is what the machine performs well at and designed to do.
Professional operators....hoes, FEL and dozers are not putting around at 70% throttle, they know better!
I find that my BX and B's run fine at 70% of rated RPM, but it still runs and performs much better at 90-100% rpms.
I'll tell you this - run it where it is designed to run...change the fluids often and IT WILL LAST damn near forever....
Run it at a lower rpm and think you are helping the situation and you will soon see after a couple of 100 hours.....something is amiss.
My BX works very well at 3000 - 32000...it almost sings...my B's are singing at about 2600 rpms....and both have different WOT settings.
Your machine - do as you think is best.
Certainly agree with this. I used to be one of those operators. As Hokie says, we always ran equipment at or near full throttle. Diesels are designed to be run like that and they last for tens of thousands of hours. I always run my B2650 at 85-100% when doing work.
Diesel pickups are most assuredly not designed to run WOT for hours on end. Semi's are getting closer, but they'd get speeding tickets if they did.
85Hokie
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pickups don't run hydraulic pumps either....
a diesel truck engine and tractor diesel engine have a lot in common......
they burn diesel fuel.
Not to get into a “flippin” useless debate, technically they kind of dopickups don't run hydraulic pumps either....
As I said before, none of you guys are going to wear out your engines by running them too fast.
Here's an example - the L2501 has a rated speed of 2200RPM and a max engine speed of 2500RPM. Now the L3301 has a rated speed of 2600RPM and a max engine speed a couple hundred RPM higher.
Both are 3-cylinder engines, closely related in design, and both nearly identical displacement.
By your arguments, the 2501 engine will last longer *by default* which I highly doubt to be true.
I ran a 4-foot flail mower off my B2920 for a few years, mowing all day long. I always ran at WOT. In thick grass, that mower needed every bit of power available. Now some mention there is no point to running beyond the rated power RPM, but consider the additional speed you get on the implement and in the tractor itself.
Here's an example - the L2501 has a rated speed of 2200RPM and a max engine speed of 2500RPM. Now the L3301 has a rated speed of 2600RPM and a max engine speed a couple hundred RPM higher.
Both are 3-cylinder engines, closely related in design, and both nearly identical displacement.
By your arguments, the 2501 engine will last longer *by default* which I highly doubt to be true.
I ran a 4-foot flail mower off my B2920 for a few years, mowing all day long. I always ran at WOT. In thick grass, that mower needed every bit of power available. Now some mention there is no point to running beyond the rated power RPM, but consider the additional speed you get on the implement and in the tractor itself.
That's good info to know. Any hour meter I've ever added to equipment has been simple time counters that turn on when the engine is running and off when not. Also, I've not put an hour meter on anything in the past 8-10 years. Sounds like the newer electronics are, well, newer
I'm guessing my hour meter reads low then since I reduce to idle every time I step off the tractor.
I'd expect the L2501 to last longer. From what I've read the tier IV engines need to be used with minimal warm up to keep from loading up the DPF. It's also an expensive system to fix, so once they get older with higher hours, a tractor that has problems with the emission system becomes a parts machine. The lower RPM's should be good for a little extra time between overhauls as well, just not enough to worry about.
I’m not afraid of a DPF and neither should anyone else. These things are on basically every new diesel road vehicle and most off road diesels as well. I’ve got one on my 6.7L Ford pickup and one on my 6.7L Ram pickup, as well as my Kubota MX. No issues with any of them. I don’t even contemplate how hard I’m running them. In fact, last fall I was doing an outdoor project late into the night and I idled my MX for 3 hours straight just for lights and didn’t think twice.
Troverman, you have to understand some folks need something to worry about, it's their nature. Do you suppose they buy a new car and expect it to last a lifetime by idling it around?
When I'm running my trencher (40 HP) I have it at about 95% throttle all day long. It a Ford industrial gas engine, and a 1982 model! Starts, runs like a top.
I called a friend this afternoon to see if he wanted to come with me to the farm. I needed to remove a log lodged in a water gap. Thought it would be nice to have someone else there in case of some trouble. No cell service down there.
His answer was, "Are there ticks down there?" I promised him there were some there but I couldn't confirm the quantity. He just started complaining. I kept driving. Finally, I told him to stay in the house, I wasn't coming by. It's just his nature, a worry wart.
When I'm running my trencher (40 HP) I have it at about 95% throttle all day long. It a Ford industrial gas engine, and a 1982 model! Starts, runs like a top.
I called a friend this afternoon to see if he wanted to come with me to the farm. I needed to remove a log lodged in a water gap. Thought it would be nice to have someone else there in case of some trouble. No cell service down there.
His answer was, "Are there ticks down there?" I promised him there were some there but I couldn't confirm the quantity. He just started complaining. I kept driving. Finally, I told him to stay in the house, I wasn't coming by. It's just his nature, a worry wart.
sdt,,, the bx 2670 hour meter is not a revolution counter. It measures tenths of hours the same at idle as it does at max eng speed. I just spent 30 minutes on mine checking it.
BAP
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There is very little chances that anyone on this site will use their Kubota enough to wear out the engine. You would have to put on 10-30,000 hours or more which is A LOT of use. Before I became disabled and farmed, we had a John Deere 444H wheeled loader that we used to load feed for cows. That loader ran between 6-10 hours a day, 7 days a week, 365 days a year. When I left the farm it had around 25,000 hours and still going strong with No engine work done on it. Kubota engines are every bit as good or better than that Deere engine. I personally would spend any time worrying about trying to run my tractor engine a little slower to add life, because odds are slim that it is going to make any difference. The biggest killer for engines is idling. Work them, keep the oil changed, fuel fresh, and air clean.
There are other reasons than engine wear to run it slower than WOT or 95%, or whatever , lot less fuel burn, less noise, easier to control...etc.
The main point is to dispute the theory that it’s bad to run it slower than PTO speed or WOT, because that’s it’s designed speed, like some here profess, it’s the opposite, it’s less wear.
I don’t run at WOT because I don’t need to, and am not at all worried that causes damage, and don’t think anyone else should worry that doesn’t want to run WOT or PTO speed either.
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The main point is to dispute the theory that it’s bad to run it slower than PTO speed or WOT, because that’s it’s designed speed, like some here profess, it’s the opposite, it’s less wear.
I don’t run at WOT because I don’t need to, and am not at all worried that causes damage, and don’t think anyone else should worry that doesn’t want to run WOT or PTO speed either.
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Not familiar with BX 2670 or what type of hour meter is employed therein.
That said, most (all?) cable driven mechanical tachometers with integral mechanical hour meters are revolution counters rather than hour meters.
SDT
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Kubota CUT/SCUT diesel engines, like light truck diesel engines and CUT/SCUT engines manufactured by others, are throw away designs, not intended to be rebuilt except in unusual circumstances. They are not Detroits or even 50 year old JDs. They will not go 30K hours. In typical CUT/SCUT service, most will not go 10K hours.
This is not intended to be condemnation of such engines, Kubota or otherwise, as such designs are appropriate and cost effective for such applications.
SDT
tradosaurus
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The reason I run my L3301 at 2,000 rpm or greater all the time is because of the stupid emission controls.
I would rather my tractor regen while I'm operating it.
I would rather my tractor regen while I'm operating it.
Can't fault you for that.
Once up to operating temperature, I usually operate my B3350 near rated speed for the same reason.
SDT
Agreed.
Once had a new NH T4050 SS Deluxe. For unrelated reasons, I sold it several years after buying with about 50 hours on the meter. About 25 of the hours were racked up by the dealer when they left the key on overnight after listening to the stereo all day.
SDT