pto gearbox speed increaser

[ns_in_tex]

I think I would like to be able to mow with much lower rpm's on my tractor engine. Does anyone know of a pto gearbox speed increaser? It would be nice & much quieter to be able to run the engine at say, 1600 rpm while mowing, & still get 540 output.

 

[kayssupply]

The easiest way would be to get a Yanmar tractor. They have a 4 speed PTO 560/730/940/1200. I use the 730 at 1800 all the time in low grass.

 

[chim]

On my B7500, the PTO goes 540 RPM with the engine at 1500 RPM and the PTO selector in the 1000 RPM position. I brought a mechanical tach home one time and checked it. Figured it could come in handy sometime. I use the RFM to rake leaves in the Fall..................chim

 

[jhburke]

Chim
My B7500 has a mark on the tach for 540 pto. It is closer to full throttle than not. Does yours have the same mark?

 

[chim]

Sure does. The 540 (PTO RPM) mark is at about 2600 engine RPM's.

Sorry if I misled you earlier. The selector is either 540 or 960, not 540 or 1000 as I typed it. I did check and got 540 PTO RPM's by operating the engine at 2600 RPM's, and also by placing the selector lever in the 960 position and doing 1500 with the engine.

Using the tractor at 1500 engine RPM's seems like it borders on "lugging" it unless you're doing really light work..........chim

 

[justractors]

Most of the small diesel engines are designed to work best at the higher rpm. If you were to get a torque curve chart you would find that they produce the most torqe and horsepower at or near their maximum governed rpm.
The will will lug down, using more fuel and creating more engine wear, if a heavy load is placed on them at a lower rpm.
The reason they have the different pto rpm positions is due to some pto driven implements require higher pto revolution input.

Of course this is just my humble but well thought out opinion.

Bill

 

[ns_in_tex]

I continue to learn more every day off tbn. I did not know they made a tractor with 4 speed pto. I sure wish someone would let us make a wish list, by taking the features off each tractor we had used & build one tractor with all the features.
I guess this might make the perfect tractor.

I don't think another tractor is in the cards for me.
Thanks,

 

[ns_in_tex]

Chim,
I do likewise on my 105 hp hesston with a 20' bushhog. When mowing weeds in the pasture I put it into 1000 rpm pto & run the engine about 1500 rpm, then when mowing heavy stuff, I put it in 540 rpm & run the engine faster.

I don't think my L4610 has but 540 PTO.
Sure wish it did.

 

[ns_in_tex]

Something I don't understand is on the torque chart for my L4610, it shows to reach maximum torque at about 1500 rpm, then slowly fall as engine rpm's rise. At the same time the brake hp continues to rise as the rpm's rise.
How can you have maximum torque at nearly 1/2 the rpm's, but maximum hp at top rpm's?

 

[cmsedore]

Horsepower (roughly speaking here), is speed * torque. So, as speed rises, torque falls off (but not proportionally, or the HP would stay constant). Perhaps someone more knowledgeable on the physics of IC engines will enlight me (us) as to why this is the case.

-Chris

 

[hosejockey2002]

Most of the grey market tractors have multi-speed PTOs. My Yanmar YM1401D has 3 speeds. It's not as fancy or easy to use as the new orange, green or blue tractors but when it comes right down to it it accomplishes the same things.

 

[bigpete]

I do not profess any expertise in this area, but have bookmarked a page with a pretty good explanation of the torque/horsepower relationship. The author explains the basics in terms of autos and drag racing, but the principles are the same
<A target="_blank" HREF=http://www.datsuns.com/torquehp.htm>Torque and HP</A>/w3tcompact/icons/clever.gif

I wish Muhammed would come up with a smiley face like that one but a perplexed face with the mortar board and tassel tilted and the guy scratching his temple.

 

[rbargeron]

Hi Neal - I was able to add the necessary parts to convert my single speed pto to a two-speed. Check out <A target="_blank" HREF=http://www.tractorbynet.com/cgi-bin/compact/showflat.pl?Cat=&Board=owning&Number=102451&page=28&view=collapsed&sb=5&o=&fpart=all&vc=1> THIS THREAD </A> for details on how it was done. Kubota sells tractors in countries where higher rpm implements are common. If you track down the right parts list you may be able to get what you want right from Kubota.

Dick

 

[ns_in_tex]

Thanks for the info. I will try to check into it.
I was wondering if your tractor came with a empty slot for the 2 speed pto control lever? If so, this might be an indication for me to look for on my tractor & possible tell if this might be an option.
Also approx what did the parts cost for your conversion?

 

[rbargeron]

My tractor had a engage-disengage pto selector lever already. If you look at some of the posts halfway down the thread there are some pictures of the pto gearbox and the parts I got for it. The parts cost about $500.

For your tractor, the place to look is a parts list - possibly the Australia or New Zealand version of the list.

 

[rbargeron]

Neal - I should have mentioned that I had looked into speed increasers - found an old Milwaukee Gear listing for one - very expensive - and big - rated for 100 hp I think. One reason they're expensive is they have to have two sets of gears so they still turn the right direction. I never found a smaller one (40-50hp) but I did find where other countrys' versions of my tractor had a 2-speed pto.

Hope you find something - let us know if you do.

Dick B.

 

[Miklos]

My Kioti LK3504 has a two speed pto, 540 and 1000 rpm. I do most of my mowing in the 1000 rpm position running the engine at 1800 rpm. With 35hp, there is no bogging when running a 5' Bush Hog mower. Fuel useage is drastically reduced over using 540 position and 2700 engine rpm.