PTO Over-Running Clutch / Adaptor (Roll-Pin Type) 1-1/8" x 6 Spline Female End, 1-3/8" x 6 Spline Male End

Brand New Over Running Clutch, 1-3/8 male x 1-1/8  Female.

This unit is attached to the PTO out put of the tractor with a roll pin. Simply remove the grease fittings and install the roll pin through through the hole in the tractor PTO shaft.

This is a High Quality unit. It is the same unit sold by TISCO, TSC and others. There other units out there that cost more and are of lessor quality. See below for where this is used.

We also have quick release PTO versions as well.


The simpliest, and earliest, form of PTO is the transmission PTO. The PTO shaft is ly 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 transmssion, 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 ion. 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.Over Running Clutch 1-3/8 Male x 1 1/8 Female.