Optimal Operating RPM

[farmerdave]

I am a new owner of a L3130HST (about 40 hrs). I'm looking for some guidance on the optimal operating RPM of the engine. The only guidance I got from the dealer was: "don't operate it below 2000 RPM". I realize that when running the PTO, I set the engine RPM for a PTO RPM of 540 (translates to about 2640 engine RPM). However, I'm not sure of the best RPM to run the engine when doing work without the PTO. 2600 seems a little high. So far, I've been running it at about 2300 to 2400 for most work. I don't know how I arrived at that, other than the engine feels and sounds smooth. Any advice on the optimal engine RPM for various types of work?

 

[odleefs]

Dave,
You should match the RPM for the task at hand. Your current method of "it feels and sound smooth" suffices, but this optimal RPM will vary based upon the difficulty of the job for your tractor. Good Luck and Have Fun!

<font color="red"> Welcome to TBN!</font>

 

[JoeL4330]

If you have an intelli-panel, find the engine RPM that gives you PTO-540 RPM. Manufacturers generally arrange this so that the required engine RPM is just PAST the engine torque peak. That way, if the engine bogs down momentarily, it INCREASES torque ...pretty clever. So, if you are doin' real work, that is the best set point. I have a L4330 HST and 2400RPM, it is.

 

[Egon]

I have a Kubota B7100HST. I've found all works best at full throttle minus a bit as it has no tack.

Egon

 

[B2400]

My B2400 feels comfortable running at approx 1900 rpms for loader work and such. It makes plenty of power and the hydraulics work at the "right" speed for me there. A side benefit of operating at lower rpm is a small savings in fuel consumption. Basically, as said before, find the rpm that feels right for you and you've found the "sweet spot" for tractor operation!

 

[have_blue]

Dave,

The goal is to run at the lowest RPM that will do the job without lugging the engine. That's why tractors have throttles. Using the throttle and transmission cleverly, you can keep the engine speed down much of the time. That saves fuel, and also saves you from the neck-snapping starts you get when running at high RPM. Once you know the sound and feel of lugging, you will learn to avoid it.

That said, running at 2000 RPM is not that harmful or wasteful. However, 2600 RPM should be avoided if possible.

 

[Bob_Young]

I agree, have_blue. That's the way it works with geared tractors anyway.

Most of my snow moving with the L4300 is done in a lower gear at around 1300 RPM; around buildings or other vehicles I may be down to 1000 RPM. The engine scarcely seems to be loaded so I see no harm. I use the foot throttle alot in this type of work.

For loader work, 1500 RPM seems to make things move fast enough for me. Probably wouldn't go above 1900 even if I was in a big hurry.

Mowing with the bush hog, RPMs are usually set anywhere from 1600 to 2000 RPM (540 PTO comes at 2473 RPM) in low/third or fourth gear. Most of the time I'm at 1900 RPM with the job getting done and the engine running easy.

I've made a turn or two at 2400RPM with the bush hog. The engine seems to be howling, but the cut job isn't any better...that I can see.

I feel sorry for you HST guys who have to keep 'em spooled up all the time. Seems like the lower end of your operating range is the upper end of mine. /forums/images/graemlins/confused.gif
Bob

 

[farmerdave]

Thanks to everyone who replied so far.

I sounds like the need for higher engine RPM's might be unique to tractors with HST transmissions. Is that true?

 

[Egon]

Also when using hydraulics.

Egon /forums/images/graemlins/grin.gif

 

[frank_f15]

if doing loader work or BB work or moving sono i usually run about 1800 RPM with my B2400 sometime a tad more, depends on the job. PTO SPEED is 2600.