129 hub assembly
 

The shear pin broke and when I took the hub assembly off there were two semi-circular cut-outs where the dowel presses against the grooves in the hub. Are those cut outs supposed to be there or were they worn into the grooves by the old pin?

A picture would certainly be helpful. All of my 129's (I've had around 5 of them) have had a little channel cut out of the hub. However, if the channel is worn away, then it is time for a replacement--that is why a picture is necessary to assess your situation.

Cub Cadet 123

Those grooves are not supposed to be there. The pin hammers against the sides of the slots and causes the grooves. They can be welded up to repair the hub but will return over time. Some guys choose to replace the driveshaft with the Quietline style shaft with the flex joints on both ends.

Makes sense, thanks

Could I see a picture of this? Interesting how you can pull parts from other cubs into the mix. I'd like to see this.