Advantages/Disadvantages of Live and Tranny Driven PTO?

[Soundguy]

I don't know how one could support that statement... I'd think that in all actuality, a transmission-driven PTO with an Overrunning clutch or even a Live PTO may be a bit safer to operate (if you can even quantify that) than an Independent PTO in the event of a breakdown or whatnot... since when you step on the clutch, EVERYTHING stops. Independent PTO must be disengaged with the lever, which isn't quite as "automatic" as stepping on the clutch when the machine behind you starts trying to beat itself or whatever got underneath it to death.

I see 2 issues with that though.. When you stomp a clutch.. you just disengage the engine power.. if the mower is spinning wildly... it will still spin wildly with your foot slammed down on the clutch.

Many independent pto also have a pto brake... ie.. when you turn of fthe pto.. it is quickly slowed to a stop.

There are ways to mitigate this.. dumping a throttle will dump pto speed... this will help with either setup.

soundguy

 

[POC]

I had the infamous "bushhog pushing the tractor" happen to me. Scary stuff if you are mowing on a hill, or near trees, and the tractor doens't stop when you expect it to!

 

[turbopiper]

I see 2 issues with that though.. When you stomp a clutch.. you just disengage the engine power.. if the mower is spinning wildly... it will still spin wildly with your foot slammed down on the clutch.

Many independent pto also have a pto brake... ie.. when you turn of fthe pto.. it is quickly slowed to a stop.

There are ways to mitigate this.. dumping a throttle will dump pto speed... this will help with either setup.

soundguy

On my Mahindra 2310, I have a 3 way switch, manual/off/auto, plus I have a button to press to engage power to the PTO.

During manual the PTO still spins when depressing the clutch or raising it, during auto it shuts down when depressing the clutch or raising the tiller up.

The book descibes the PTO as Wet,Multi-Disc,Hydraulic. So is this a live PTO or an independant PTO. Maybe I'm getting confused as to what" live" is.... always on?
Ted

 

[xlr82v2]

TP,

What you have is an electrically controlled Independent PTO. It actually is not controlled by the clutch at all, but a microswitch on both the clutch linkage and the 3ph control lever. That's what "Independent" refers to... the PTO is Independent of the clutch/transmission... you still have full power to the PTO even though the clutch is fully depressed and the transmission is not mechanically connected to the engine. An Independent PTO has it's own clutch, independent of the transmission clutch.

A "Live" pto usually has a 2 stage clutch, where the first clutch stage connects the transmission to the engine, and the 2nd stage connects the PTO to the engine. So, you can depress the clutch pedal through the first stage and stop and shift gears while maintaining full power through the clutch to the PTO. Then, if you fully depress the clutch pedal further through the 2nd stage, both the transmission AND the PTO are disconnected from the engine, and there is no power transmitted to the PTO.

Hope this makes it a little clearer than mud...

 

[Soundguy]

Yep.. .. but remember.. independent pto is by definition.. live as well.

soundguy

 

[xlr82v2]

Soundguy,

Yes, you are correct. By default, an Independent PTO is "Live". Proper terminology would probably be "Live Independent PTO", and "Live PTO."

And again, you get the last word in...

 

[Mace Canute]

I remember back in the 60's, a neighbour had a Massey tractor (IIRC) which had both live PTO and transmission driven PTO, user's choice at the flip of a lever. Apparently when combining, if he plugged it he would just flip from "live" to "transmission driven" and back up...the combine would run in reverse and cough up the wad of straw. Then he would start up again normally and take it a little easier and keep on going without breaking a sweat! Plugging a pull type combine without being able to do the "puke it back up" option usually resulted in a lot of work getting it unplugged and you quickly became a lot more cautious when you came upon a spot where the straw was thicker or tougher than usual.

 

[Soundguy]

I believe you are confusing 'ground speed' pto, and 'tranny pto'. regular tranny pto spins off the counter shaft usually.. and always goes the same direction reguardless of gear the tranny is in.. including neutral.... Ground speed pto ont he other hand.. could reverse..

soundguy

 

[Mace Canute]

Yes, I definitely have the two terms confused Can I attribute it to having a brain fart?

 

[Soundguy]

We all get those from time to time!

soundguy