PTO Overrunning coupler

Stubbyie

New member
Jul 1, 2010
879
7
0
Midcontinent
Not certain what is meant in the post about the tractor being 'automatic'. Perhaps 'hydrostatic' is meant instead.

Hydrostatic isn't going to be connected to the PTO.

Still assuming, I suspect your machine has a switched PTO--on, off, push a pedal, flip a lever, something.

You almost certainly don't need an overrunning clutch on the PTO driveline.

You might consider a slip-clutch on the driveline of a bushhog, but that's a different animal.

If you push in the clutch of your machine, it stops, right? On the old Fords you could push the clutch in and if the bushhog was spinning the tractor would continue running forward due to the motion of the PTO driveline (transferred from the rotary motion of blades) being connected to the drive wheels regardless of clutch being depressed.

A lot of the old Fords ran into a tree, pond, or fence before overrunning couplers were introduced.

Since I'm postulating here I welcome other input from those far more knowledgeable about these particulars.

Please post back your continuing experiences so we may all learn.
 

TripleR

Active member

Equipment
BX2200, BX2660, L5740 HSTC, M8540HDC and some other tractors and equipment
Sep 16, 2011
1,911
8
38
SE Missouri
We have some old Fords as well as two BXs and as tinkerswiteverything said, BX has independent PTO, not transmission driven like the old Fords and others, so no external over running clutch needed.
 

Fastdonzi

Member

Equipment
New Grand L3560
Dec 4, 2015
64
1
6
East Tn
We have some old Fords as well as two BXs and as tinkerswiteverything said, BX has independent PTO, not transmission driven like the old Fords and others, so no external over running clutch needed.
I bought one for my New Kubota, then found this site and learned I didn't need it :) My 8N, 9N, and Golden Jubilee had them so I figured it was necessary ...
 

TripleR

Active member

Equipment
BX2200, BX2660, L5740 HSTC, M8540HDC and some other tractors and equipment
Sep 16, 2011
1,911
8
38
SE Missouri
May be handy for future reference.

From Tractor Data

Power Take-Off (PTO) Types

There are three basic types of PTO control on a farm tractor:

Transmission

The simpliest, and earliest, form of PTO is the transmission PTO. The PTO shaft is directly connected to the tractor's transmission. The PTO is only working when the tractor's clutch is relased, so if you take the tractor out of gear while slowing down the PTO will stop working. This is a disadvantage in applications such as mowing.

An overrunning clutch is often needed with a transmission PTO. Without it, the driven equipment (such as mower blades) will put a force on the PTO shaft, and then the transmission, due to inertia. The equipment will "drive" the tractor, and you will still move after using the tractor's transmission clutch. An overrunning clutch prevents this from happening by allowing the PTO shaft to freely spin in one direction. In more recent models, this is built into the tractor. In older tractors, it is an extra piece of equipment mounted on the PTO shaft.

Live (two-stage clutch)

A live PTO works with the use of a two-stage clutch. Pressing the clutch half-way will disengage the transmission while pressing it fully will disengage the transmission and the PTO. This allows the operator to slow down or change gears while the PTO is still operating.

Independent

An independent PTO means that the PTO shaft is controlled with a separate clutch. As with a live PTO, this allows for full control over the tractor while separately controlling the PTO. There are two major types of independent PTO; mechanical and hydraulic. A mechanical-independent PTO uses a separate on-off selector, in addition to the PTO control lever. Often the tractor must be stopped or off to change this selector position. A hydraulic-independent PTO uses a single selector.