What RPM's do you run at when using PTO?

KiotiJohn · Mar 16, 2005

Re: What RPM\'s do you run at when using PTO?

As has been said, diesel engines are designed to run constantly at their rated speed, so you'll do no damage there. Running slower than rated RPM (540) on the mower, can change the dynamics of the pressures on the gear box, possibly actually wearing it out a little faster, or at least this is what I've read and heard.
One other thing about running lower is that if you hit something at rated speed, you have a better momentum for the blades to go through it. At a slower speed the momentum may not be enough to keep the mower from jamming or throwing the object. Of course, one could argue that more damage could be done at the faster speed if the pin doesn't brake first. John

PineRidge · Mar 16, 2005

Re: What RPM\'s do you run at when using PTO?

I like to stick with the recommended engine RPM setting for the 540 PTO speed so in my case if I'm running the finish mower or the rotary cutter I'm at 2600 RPM's and humming. Noise isn't a factor since most of my mowing is done with a set of headphones so I can still hear my tunes.

You see my tractor loves the country but I still get my dose of rock-n-roll. /forums/images/graemlins/cool.gif

texbaylea · Mar 16, 2005

Re: What RPM\'s do you run at when using PTO?

Since my Kubota gives PTO revs I set it to 540 rpm unloaded for the shredder (Bush Hog) and then adjust forward speed to keep it between 520 and 540 rpm. For my Woods chipper/shredder, I set it to 540 and let it run..

I agree that diesels are designed to run at such speed all day long.

Vernon

Bird · Mar 16, 2005

Re: What RPM\'s do you run at when using PTO?

( Post hole digger- just above idle )

Yep, Vince, that's definitely one you don't want to run at the 540 speed, especially when starting it into the ground or lifting it out. /forums/images/graemlins/laugh.gif

_RaT_ · Mar 16, 2005

Re: What RPM\'s do you run at when using PTO?

( Rat, you're probably right for the work you're doing with your tractor, but like Charolais said, I don't think that hay mower/conditioner or the baler I used to pull would have worked well at all at a slower speed, and even with my little tractors and implements, I figure running the engine and PTO at the speed the manufacturers made them for let me drive just a little faster and get more done in the same length of time. )

True enough Bird. I figure you just have to experiment. If folks find getting the best cut is at PTO RPM which tends to vary with tractor brand and model, thats great. I have experimented and will stick with 2300 RPM or so for finnish mowing, aboout 2000 for loader work, sometimes less. There is no question noise goes up when engine RPM does, theres no getting around that. It's not that my tractor is noisy, I suppose it's that my ears are that sensitive. One thing I really liked about my old International was PTO speed was at 2200 RPM and it even had a 1000 RPM PTO in addition to the 540.

slowrev · Mar 16, 2005

Re: What RPM\'s do you run at when using PTO?

Please note that all tractors do not require 2600 RPM for 540 PTO RPM. Whatever your tractor tach/manual calls for will be fine. On my particular gasser it is 2000 rpm. If you keep your revs at or below the specified RPM you will always be ok, except for some attachments such as post hole augers. As others have said, you can sometimes get by with lower PTO RPM's.

Ben

PineRidge · Mar 17, 2005

Re: What RPM\'s do you run at when using PTO?

On Class III Boomer's we have a neat little green 540 light that illuminates once the PTO comes up to 540 RPMs Likewise there is also a red over PTO RPM light as well so it keeps me honest when mowing and eliminates guesswork.

_RaT_ · Mar 17, 2005

Re: What RPM\'s do you run at when using PTO?

On the Kubota L30 series, there is a display that shows you the speed of the PTO, thats how I know I'm at 480 to 500 RPM when mowing.

RalphVa · Mar 17, 2005

Re: What RPM\'s do you run at when using PTO?

Mine is 2900 rpm for 540 @ the PTO. Diesels are designed to run full throttle all day. On my Benz it's 4300 rpm. I run it to that rpm most of the time in 1st and 2nd gear because it only has 65 hp and needs all the power to get under way and not be a slug. It sounds fine at 4300. That's about 92 mph in top gear. Could run at that all day long at that speed if I could find a highway to do it on.

Ralph

bdog · Mar 17, 2005

Re: What RPM\'s do you run at when using PTO?

I assume there is a linear relationship between the 540 and the 1000 pto rpm? My tractor is selectable. If I had the selector at 540 and had 540 at 2600rpm, would I be able to get 540 pto rpm if I set the selector to 1000 and kept my engine rpms at 1300?