PTO Confusion

Here is my cut at it, but other posts here seem to disagree:

1. "Dead" PTO
If the PTO is engaged and one is bush-hogging along and presses in the clutch and the spinning bush-hog (assume no overrunning coupler) continues to push tractor forward, then the PTO is "Dead". The PTO power is cut off the second the clutch disengages forward motion, but still pushes the tractor forward until the bush-hog stops spinning.

2. "Live" PTO.
If the PTO is engaged and one is bush-hogging along and presses in the clutch and the spinning bush-hog (assume no overrunning coupler) DOES NOT push tractor forward, then the PTO is "Live". The PTO power is cut off the second the clutch disengages forward motion, and the bush-hog can spin to a stop without pushing the tractor forward.

3. "Independent" PTO
The same as "Live" PTO; The PTO is "Independent" from the drive train of the tractor, except for the clutch.

4. Some tractors have a "Two Stage" clutch, which is, in essence, a separate clutch for the PTO and transmission. Half way down stops power to the wheels, but continues to drive the PTO. All the way down stops power to both. While all PTO's I have seen with Two Stage Clutches fall into the "Live" category, there may be some out there that the spinning bush-hog will push forward.
My point is that, in my understanding, a Two Stage Clutch does not "make" a PTO live or dead.

Please correct the error of my ways!

By the way, I briefly searched the article archives here and found nothing. Perhaps someone could write an article on this terminology for us?

Thanks,
Tommy D.

I think with "dead" PTO, you are referring to "transmission" PTO. This setup uses just a single disc clutch, and the PTO drive stops when you depress the transmission clutch.

Live PTO uses the two stage clutch you described earlier. Pushing down on the pedal halfway will stop forward travel of the tractor while the PTO continues to run. Pushing down all the way will stop the PTO also.

Independent PTO means the PTO is controlled completely independent of the clutch pedal. These are generally hydraulically actuated with a multiple disc wet clutch, and are not affected in any way by clutch pedal operation.

So I think you came pretty close except on the independent PTO.

Ok, I have a tractor (US Kubota, to be exact) and when bush-hogging I push in the clutch and both tractor and PTO stops being driven. Tractor can stop and bush-hog spins without pushing tractor forward. In other words, no 2 stage clutch, but PTO does NOT push tractor forward.

Is this considered "Live".

My neighbor has an 8N. If he removed the overrunning clutch from his PTO shaft and was bush-hogging and pushed in the clutch, power would stop being delivered to the PTO, but the tractor would continue to move forward as long as the bush-hog was spinning. In other words, as long as the PTO shaft is spinning, it is pushing the tractor forward.

This is what I am calling "dead" or "non-live". I guess, like you said, "transmission PTO" is a better term.

Live PTO is always associated with a 2 stage clutch, which I would guess was probably an option on your Kubota, at least with the larger ones.