PTO SPEED ADAPTER ??

[TOMLESCOEQUIP]

I'm looking for a slide on adapter that will jump my 540 pto up to 1000 rpm. I run a pto generator off my tractor & need 2800 tractor engine rpm to get 540 pto speed.

My tractor has double the HP I need to run the generator, & I'd like to cut the engine speed down to save fuel.


Hubcity still makes one new, but the cost is such that I could buy alot of fuel before I'd recover the cost of a "new' one.



Please let me know if you know of one.

Thanks.........Tom

 

[rbargeron]

Hi Tom - once in a great while a parallel pto shaft reducer shows up on eBay - an old one went for $200 a couple years ago. Japanese tractors commonly had two-speed pto's (540 and 750 or 1000 - some had all three) but I think the product liability issues may have squashed them for the US market. A few brands still have them.

My tractor model was also offered in Europe, Japan, Australia, NZ, - and 2-speed pto was included on units sold there. I was able to simply order the needed parts right off the parts list to convert the single-speed pto to 2-speed. Parts cost was around $300 if memory serves. It has worked fine for almost 6 years now. It would be nice to compile a list of makes and models where this is possible. Of course the hamsters of liability and risk might come knocking if too many people started doing it.

 

[TOMLESCOEQUIP]

Hi Tom - once in a great while a parallel pto shaft reducer shows up on eBay - an old one went for $200 a couple years ago. Japanese tractors commonly had two-speed pto's (540 and 750 or 1000 - some had all three) but I think the product liability issues may have squashed them for the US market. A few brands still have them.

My tractor model was also offered in Europe, Japan, Australia, NZ, - and 2-speed pto was included on units sold there. I was able to simply order the needed parts right off the parts list to convert the single-speed pto to 2-speed. Parts cost was around $300 if memory serves. It has worked fine for almost 6 years now. It would be nice to compile a list of makes and models where this is possible. Of course the hamsters of liability and risk might come knocking if too many people started doing it.

My first compact I ever owned was a grey market kubota that had a 3 speed pto. Then I bought a International 244 (made by mitsubishi) that had a 2 speed pto standard as well. Now I have a couple NH's a TC33D & a TC40D & don't have the 2 speed pto's I need........Go figure........I need to down grade my upgrade to run the gen !!

Tom

 

[sandman2234]

Belt and pulleys set up on an idler with pillow block bearings isn't too hard to set up. Depending on what hp your pushing, you might need to go with 3 or more belts. Buying pulleys new can be expensive, but are often found in machine boneyards.
David from jax

 

[Soundguy]

Don't assume that 1/2 pto rpm = 1/2 pto hp... it usually doesn't due to most companies putting their pto rpm right inthe sweet spot of the hp peak. running at half pto rpm may give you much lower than half pto hp.

Add to that that engine rpm doesn't not completely dictate fuel usage.

Work done is a bigger determination of fuel usage.

As an example.. think about this. I have 2 largish diesel tractors... a 1975 ford 5000 with 70 hp, and a 2002 NH 7610s with about 95 hp.

Using a 10' mower to mow my pasture, guess what... each machine uses about 5g of diesel to mow my pasture. Same gearing on the tractors, so time is the same. Using yuor logic you would expect the 95 hp tractor to consume more fuel.. but in fact it consumes no more fuel than the 70 hp tractor that is doing the same job. Here's another kicker... I can throw a 15' mower on the 7610s, and mow in less time, and still use the same 5g of fuel. Further proof that it is 'work done'.. not 'time used' to base fuel consumption on.

There is only some much per/unit work you can get from a set amount of fuel. look at your electrical laod, pto load, and estimated hp usage... that should give you a pretty good idea of fuel needed to generate that electrical power. It probably won't make a huge difference in fuel used whether you run at pto speed or half pto speed with a gear box inline... you aee still generating 'x' electrical power... and WILL use 'y' fuel to produce that power. Can't escape physics.. only 'scotty' can do that..

If your tractor is in good condition.. it won't have any problem running at 'rated' speed for long durations, as long as it has some load on it...

soundguy

I'm looking for a slide on adapter that will jump my 540 pto up to 1000 rpm. I run a pto generator off my tractor & need 2800 tractor engine rpm to get 540 pto speed.

My tractor has double the HP I need to run the generator, & I'd like to cut the engine speed down to save fuel.


Hubcity still makes one new, but the cost is such that I could buy alot of fuel before I'd recover the cost of a "new' one.



Please let me know if you know of one.

Thanks.........Tom

 

[rbargeron]

Good post Soundguy. It's exactly right that work done = fuel coverted. I just like running my engine slower so it makes a bit less noise, is easier on the clutch, and it happens to lay better into the whole gear ratios/tire size/ground speed thing - even if the brake-specific fuel consumption is a few percent higher. There's also an improvement in friction losses at lower rpm that helps offset the lower thermal efficiency. Pretty hard to measure the net difference. Back in 2002 when I modified my pto gearbox, another reason was I wanted to spin up a few low-hp implements a little higher, a sicklebar used for edge trimming, single-stage snowblower, water pump..

 

[Soundguy]

No problem as long as you know what to expect going into it.

I'm sure there will be plenty of applications where a multi-speed pto setup actually works out great.. especially when the implement really needs less.. or much less than the tractors full output. For instance.. a 100 pto hp tractor running a 20 hp load on it's pto.. could concievable run at half rpm, and probably a bit less than half power.. and still have 2x the pto hp needed to do the task.. Sitituations like that where you do not exceed hp needed.. it's not a bad idea..

Soundguy