PTO failing to enguage

I have a 100hp 10011 model Zetor, I am have a problem with the PTO. When I attempt to enguage the PTO under load, it constantly slips out. I have place a couple of shims (spacers) in the clutch, however this has not recitified the problem. Can anyone offer a solution to this which does not involve the replacement of the entire clutch?

Greetings Bill, I have some recent experience with PTO popping out on a 4340. There are three "fixes". The simplest is to replace the detent spring on the PTO (the left-most detent on top of the trans.) The second is to remove the PTO shaft at the rear and see if the circlip has disengaged from the shaft and replace the circlip. Finally there is an upgrade shaft assembly which replaces the PTO shaft and the shifter Part Nos. 60122016 & 60122017. This last fix took care of my problem, but remember the foregoing was for a 4340 and the repair manual was for 3320's to 7745's. Other part numbers may apply to your tractor. These last two fixes required draining the differential and the last required removing the top of the differential case (under the seat). Good luck. Nick

My 3320 had the circlip failure. fixed for about $0.40 US

Tony