I recently visited a discussion about a woodruff key popping out of the backside of the small gear on the right side. Someone offered to make a collar to keep that key from slipping out...can anybody tell me who that was. I need one desperately.
You can usually press the key into the slot far enough with some locking pliers for the gear to go on without pushing the key out the back.
If it still won't work, you can shave a small amount off the top of the key to make it work.
The problem is the back almost one third sticks out and is not covered by the gear. Consequently it pops out from the backside of the small gear and no longer serves its function.
If you have that much of the key covered by the gear it shouldn't be able to rotate up & out.
Double check that the key is staying square in the slot as the gear goes on.
It is square in the slot and it has popped off twice and was all chewed up. Used another woodruff key and started over. Even made sure the screw was extra tight and still came out the back side.