Well, what does it say in the instruction manual for modern high HP tractors ?
Found this in my 7810 manual.
Found this in my 7810 manual.
Pto speed on mower
- Thread starter oakleaf
- Start date
IME of 10 series you'd be lucky if the pto worked .
11,500 hrs....engine, gearbox, backend untouched. I'm happy with that.Something Fendt owners can only dream of....
- Location
- The North
ha ha our old mf 2620 was same, still got 1000 shaft and bit to swap it in the shed!
bobajob
Member
- Location
- Sw Scotland
Remind me why is it 540rpm for implements? And not the round figure of 500 and 1000rpm. Something to do with the revolutions of the engine on an original grey fergie is that right?
john432
Member
- Location
- Carmarthenshire
https://en.m.wikipedia.org/wiki/Power_take-off
American standard in 1927, so a few years before the gray fergi.
American standard in 1927, so a few years before the gray fergi.
- Location
- Matching Green
I believe it was a Farmall that was the first tractor to have a PTO and it happened to turn at 540rpm at maximum power due the gearing and so it became the standard.
- Location
- Huntingdon, UK
I thought it had something to do with least vibrations when spinning?
Cowabunga
Member
- Location
- Ceredigion,Wales
The number of splines is not critical but it is the ‘standard’. Early Series 10 tractors had exchangeable shafts that were required to be swapped to change speed and were easily recognised by the number of splines. Later Series 10 has in-cab shiftable PTO speed change so swapping shafts became optional depending on the implement shaft type. JF were one of the first to fit six splines on 1000 rpm implements that I remember. Very naughty of them, especially as they used unique shaft ends on the inner yolks and charged ridiculous prices for parts.
Firstly I should say that I understand the principles of the 540-1000 shaft torque v speed etc but can someone confirm/deny something I thought was on here somewhere. @Cowabunga is probably most likely to know for definite. It's that 540 eco is only designed for low power applications on many tractors as the internals are not designed to run things with a large power demand? Above the obvious constraints of 540 v 1000 as explained earlier in the thread, they aren't engineered to take much loading? Or is that BS? As such I have only ever used mine for spraying and fert spreading which are obviously low load.
oakleaf
Member
- Location
- South coast of Ireland
The mower will be used on a 120 engine hp tractor. Whether l go for the 540 or 1000 version l am yet to decide.
Tractor has 540 750 and 1000 ptos but mowing will not be done in 750. I only use that for fert , spraying , tedding and rowing up.
The mower is Claas and the sticker on headstock states operating range of 460 to 540 on the 540 model or 850 to 1000 on the 1000 variant. So if one was in a light crop there is the option to throttle back a bit if desired. Cant see l will be doing that though.
Tractor has 540 750 and 1000 ptos but mowing will not be done in 750. I only use that for fert , spraying , tedding and rowing up.
The mower is Claas and the sticker on headstock states operating range of 460 to 540 on the 540 model or 850 to 1000 on the 1000 variant. So if one was in a light crop there is the option to throttle back a bit if desired. Cant see l will be doing that though.
Cowabunga
Member
- Location
- Ceredigion,Wales
If it was not designed for full loads, it would warn you in the instruction manual. I’ve yet to see such a warning.
john432
Member
- Location
- Carmarthenshire
For mixing slurry, use the Jd6400 usually on full load on 540e, on the MF6475, the 540 speed is too slow, and the 1000 ,too much of a load, so use the 540e ,and revved up to 2000engine rpm (have to disconnect the selector lever speed sending switch) All the engine power is used for that job! Rightly or wrongly, often run a 4m power harrow on 1000e on easy to till land.
Cowabunga
Member
- Location
- Ceredigion,Wales
The reason they have a lower limit is to indicate to the driver when he should change down a ratio rather than lug the engine down further. The rotation speed of the knives is what keeps them stiffly out. You do not want them flapping under load or they will wear the pivot pins and ultimately not cut cleanly. Also the rotating speed ultimately dictates the maximum forward speed available where the knives cut to their maximum blade length.
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Good point. I should probably read the manual more thoroughly.
We always use trimmers on 540e and 9ft disc mowers with no conditioner and on lighter crop or topping...And have used it on a 3m 1000 set power harrow for an acre or 2 .... by mistake
Plus like you spinner and sprayer .....
.... and haybob...
oakleaf
Member
- Location
- South coast of Ireland
So not a good idea to mow at 850 then and let it drop back to 750 when you meet a hill
.Just as well l always liked to mow at full chat so.
- Location
- Near Derby
I agree with you. I think the 540E is just another gear in the 540, 540E(750) and 1000 RPM. So why shouldn't we use 540E for heavyish loads? My independent mechanic told me not to use 540E on heavy loads but couldn't tell me why. I think it is just a rumour.
A high compression engine needs to be well spinning over ? not low rev grunting on a high power requirement implement ? thats what I was always told anyway.
not pto obvs. and in a draft situation... the only 'slugging' with a tractor I do is with the plough to get that grip sweet spot in difficult conditions / tricky bits.if there are any.
Cowabunga
Member
- Location
- Ceredigion,Wales
At some point I think there were two things that perpetuated this nonsense. There were some issues with early 3000 series MF where the bearing specification on the PTO final drive was not up to par. It was one of the first to offer 750 PTO speed [not THE first though]. There was that.
Then there is the fact that supplying 540 at [say] 1500 engine rpm used to be way down the power curve on older type engines. Not so much on modern 'constant power' engines though. However, 1500 is usually on or very near the point where engines produce their maximum torque, from there down the torque drops off rather than rises [as engines lug down], so there is very little if any torque reserve at these revs to overcome increased load, whether steady or sudden. It does make a big difference when working on the limit at either engine speed. The engine running at 2000rpm+, dead on or above where it turns out maximum power, typically has a 35% torque reserve [rise] available to overcome increasing loads.