PTO, way too often is undervalued in a purchase

[Keith_B]

I belive you but I think that only works if your pto shaft is permenantly splined to the flywheel. I know with dual clutch system you have two shaft splined to two clutch plates. There is an Inner and an outer shaft. The inner shaft is splined to the pto clutch and outer shaft to transmission clutch. What I am not completely sure is if the independent pto is also a dual shaft system that the inner shaft (PTO) is splined permanently to the flywheel and with a PTO clutch pack at the back of the transmission for the pto. As long as engine is running the flywheel will turn no matter what you do to the clutch. Anyone out there to corroborate me on this?

A lot of the independent PTOs we see on CUTs are hydraulically actuated.

 

[JC-jetro]

JC, there are several inaccuracies in those statements.

Here is an informative link on PTO types: TractorData.com - Power Take-Off

Thanks Keith, appreciate your responce.

I understand your reply, what I see lacking in all the posts is clear undestanding of anatomy of PTO/ transmission design even including the link you have posted. Every one knows how their their tractor works. What I'm having difficulty with is that you have one cranksahft turing one flywheel. This flyweel has to turn two shafts namely PTO and transmission independent of one another. That can only happen with two shafts one inside another with inner directly coupled to flywheel or the pto has to be geared to flywheel directly to be independent of clutch

That is really my question. Every one keeps talking about an independent seperate clutch. that is understood.

My question is how is this pto clutch shaft coupled to engine rotation?

 

[Keith_B]

Thanks Keith, appreciate your responce.

I understand your reply, what I see lacking in all the posts is clear undestanding of anatomy of PTO/ transmission design even including the link you have posted. Every one knows how their their tractor works. What I'm having difficulty with is that you have one cranksahft turing one flywheel. This flyweel has to turn two shafts namely PTO and transmission independent of one another. That can only happen with two shafts one inside another with inner directly coupled to flywheel or the pto has to be geared to flywheel directly to be independent of clutch

That is really my question. Every one keeps talking about an independent seperate clutch. that is understood.

My question is how is this pto clutch shaft coupled to engine rotation?

The PTO is coupled to engine rotation through the tractor hydraulic system. I'm not sure of all independent systems, but on those like mine it is my understanding that the independent PTO is basically a separate hydraulically operated motor. Think of it as a hydrostatic tranny, only instead of driving the wheels of the tractor it drives the PTO shaft on the tractor. The lever or switch operates a valve that turns on and off the hydraulic flow to the PTO.

 

[JC-jetro]

The PTO is coupled to engine rotation through the tractor hydraulic system. I'm not sure of all independent systems, but on those like mine it is my understanding that the independent PTO is basically a separate hydraulically operated motor. Think of it as a hydrostatic tranny, only instead of driving the wheels of the tractor it drives the PTO shaft on the tractor. The lever or switch operates a valve that turns on and off the hydraulic flow to the PTO.

aha, we're getting some where. That's more like it... I buy that. I think they are not all hydraulically operated. Some are purely mechanical and the PTO shaft should be coupled to engine with a double shaft... I think... not very sure

Of course we're making distinction between a clutch engagement (mechanical or hydraulic) and hydraulic motor to run the pto off of hyd pump directly from crank shaft pulley in front of the engine.

Thanks again

 

[Soundguy]

Keith.. you are confusing people by omitting some very important data.

You are lumping ALL tranny driven pto's together, then making generalized statements.. like the one about the pto no moving unless the tractor is.

That actually has a name of it's own.. it's called a ground driven pto... TRhat's why you can have a reverse pto whent he tractor drives in reverse.. and yes.. MF'ers used to have that.

that's where the confusion is coming from.. Ideally when listing pto types, you would list, ground, tranny, live, and independent.

If you want to get into it even further, some tractors have an economy pto option to achieve pto speed at a reduced power, and a reduced eng speed.

There are also multi speed ptos. Some, like the jap tractors have 3 or 4 pto speeds. Some like the domestic tractors here inthe us, can be 540 or 1000 by swapping the pto stub.. as each stub is driven off a different set of gears.

The reverse pto is always a thing to look at.. I believe there is a grey kubota with a reverse pto.. as well as IH.( like a cub without the ASAE pto option ). of course.. as well as being reverse.. there may be a speed difference as well

Soundugy

JC, there are several inaccuracies in those statements.

First, tranny operated PTOs. I know of a large number of tractors where the PTO will not run if the tranny is in neutral. The clutch in these tractors disengages the PTO and the tranny at the same time. This was the reason a number of tractors came out with a hand clutch and a foot clutch to simulate live PTO (like the WD 45, my FIL's Case 430 and numerous others). On these machines when the tractor is in neutral the PTO is in neutral.

The second item that is inaccurate is the assertion that pushing in the clutch will alway kill the PTO. This is not at all true for independent PTOs, which have a separate clutch for the PTO. Most of these PTO's engage with a lever or a pushbutton and are not by any way controlled by the clutch which disengages your tranny. My Mahindra 4110 has an independent PTO, and I have a push button PTO control, to engage/disengage I push the button. The foot clutch has no control over the PTO.

The system you are describing is a live PTO, which uses a two-stage clutch. The upper part of the pedal movement engages/disengages the tranny. The lower part of the pedal movement engages/disengages the PTO.

There are manufacturers variations of each type.

Here is an informative link on PTO types: TractorData.com - Power Take-Off

 

[Soundguy]

Yikes! Though I don't know what tractor you have.. I'm gonna guess you are 100% wrong. I have only ever seen 1 tractor wher ethe pto is a hy motor.

Almost all live or indepentednt pto's and HST pto's are just coupled thru the tranny contershaft.

No magic here.. it just functions like a 2 stage clutch... except ont he independent pto, the 2nd stage of the clutch is usually a little lever somewhere.. like on my Nh 7610s and fireman pat's NH tractor. On a dual clutch tractor.. the 2nd stage is just right behind the first.

Break out an exploded diagram of your tranny before you reply please...

Soundguy

The PTO is coupled to engine rotation through the tractor hydraulic system. I'm not sure of all independent systems, but on those like mine it is my understanding that the independent PTO is basically a separate hydraulically operated motor. Think of it as a hydrostatic tranny, only instead of driving the wheels of the tractor it drives the PTO shaft on the tractor. The lever or switch operates a valve that turns on and off the hydraulic flow to the PTO.

 

[Keith_B]

Keith.. you are confusing people by omitting some very important data.

You are lumping ALL tranny driven pto's together, then making generalized statements.. like the one about the pto no moving unless the tractor is.

That actually has a name of it's own.. it's called a ground driven pto... TRhat's why you can have a reverse pto whent he tractor drives in reverse.. and yes.. MF'ers used to have that.

that's where the confusion is coming from.. Ideally when listing pto types, you would list, ground, tranny, live, and independent.

If you want to get into it even further, some tractors have an economy pto option to achieve pto speed at a reduced power, and a reduced eng speed.

There are also multi speed ptos. Some, like the jap tractors have 3 or 4 pto speeds. Some like the domestic tractors here inthe us, can be 540 or 1000 by swapping the pto stub.. as each stub is driven off a different set of gears.

The reverse pto is always a thing to look at.. I believe there is a grey kubota with a reverse pto.. as well as IH.( like a cub without the ASAE pto option ). of course.. as well as being reverse.. there may be a speed difference as well

Soundugy

Chris, I've never seen the tranny operated PTO's separated into two groupings, but it probably would make the explanations a little simpler; except for the fact that there are many that really aren't ground driven, like the Case 430 I referenced. It's tranny driven, but does reverse. As I stated before, there are many variations from those three main types.

 

[Glowplug]

Go to Tractorsmart.com, click on [INFO], then click on [Tractor power take-off].

 

[JC-jetro]

Keith,

below is a pic of your independent pto. You do have a clutch pack for your pto somewhere in your tranny and it is not a hyd motor running off of hyd pump. I also know you have a single clutch. I reckon your pto clutch is fed off of countershaft in your transmission.

1920 independent PTO

1920 Clutch

yet to see how engine rotation is coupled to your pto clutch pack.

 

[whitetiger]

The cluth cover [ref 17 of second pic], has a splined hub in the center. The hollow IPTO shaft engages these and drives a shaft any time the engine is running. The transmission input shaft runs thru the center of the IPTO shaft and is splined into the clutch disc. The IPTO clutch is engaged with hyd pressure thru a valve supplyed with oil from an engine mounted pump. The operation of one has no effect on the operation of the other.