PTO Shearing Bolt...Help? Please

HELP....I have had a very nasty instance where the bolt was sheared and the adaptor pulled away from the PTO shaft while mowing, causing a very dangerous situation.

Thanks...

Old Ag

The coupler is a female 1 1/8 to a 1 3/8 male. The female part of the coupler turns inside of the outer part which makes up the male shaft. The bolt is used to hold the coupler onto the PTO from the tractor. In doing this, the force of the PTO is transferred through the bolt to turn the outer male shaft and thus to the mower. The PTO shaft turns freely on the tractor as well as the mower shaft, thus the problem is not there, but in the coupler setup.

Do the over-run couplers I see on this site have some way to be fixed to the PTO shaft of the tractor without a bolt ? Do they have some type of retracting key to hold them onto the tractor PTO shaft hole ?

Thanks all for the info thus far.

Do the conversion shafts have a circular cutout on the splines so that my mower quick disconnect will lock onto it ? Or does the ORC couplings available have some internal key that locks the female part of the coupling to the PTO shaft that is straight such as mine is?

Or are you just saying that the hole through the ORC is the only way to hold it to the PTO? If so, the way it's supposed to work is that a roll pin gets driven through the outer hole into the the hole in the inner piece. This pin must be short enough that it only locks the inner piece. Then the hole in the outer piece gets plugged (with a grease zerk if I recall correctly). If the pin passes through both parts of the ORC, you're defeating the purpose of the ORC by locking both parts together.

Until you mentioned that the coupling was an ORC I thought you just had an adapter like I do.

If the bolt or pin is being sheared along the shaft, then you've got a problem with thrust being applied in some fashion. Most likely from either too long or too short a pto shaft, and improper fastening of the impliment and or pto shaft. Correct that situation in this case.

The adapter is a short stub that is 1 1/8 on the female end and fastens to the PTO on the tractor with a pin. The KK mower shaft connects to the adapter via a push-release locking mechanism on the side of the mower shaft.

I use a pin that I bought at Fleet Farm to lock the adapter (I think it was sold as a PTO pin). That pin appears to be hardened steel.

I don't know why your bolt keeps breaking -- do you tighten it the nut down to the surface of the adapter? If so, it wouldn't take much play in the adapter to fatigue the bolt and eventually break it. Try finding a pin.

On the other hand, maybe your mower's got a problem. I've never broken my PTO pin - not even the time a big rock jumped up out of the ground into the mower.