Recently I asked for advice to remove stuck/stripped set screws on a manual PTO. I quickly found out what a little beast of a job this is to do as in my case the set screws were all rounded out and no allen wrench would work. The clutch hub was broken on the back side (pics below) and the fiber disc was broken as well. Nothing to do but overhaul to like new service level. Here is my progress and suggestions for those who will need to do this in the future. Total time 4 hours.
1) You will waste your time without good drill bits to drill the old PTO set screws out. I found these Cobalt Irwin's to be excellent and only $1.75 ea at Auto Value Supply. They ate the metal like butta.
Drill Bits.jpg
2) Next pic is carefully drilling out the old screw. Plenty of oil and slow and precise drilling. 3/16 and then 11/64". SLOW/STEADY.
Drill out.jpg
3) Offending clutch hub is shown showing broken metal on backside of hub where PO over tightened or time destroyed it. Definitely loose but fortunately I have a spare clutch hub to use for this job.
Old Clutch.jpg
4) Next is broken disc compared to new thicker disc ($31)
Discs.jpg
5) Then re tapped holes 1/4" 20 to clean threads.
Tap clutch.jpg
6) Cleaned and repacked the rider bearing with Lucas HD green grease.
7) Reassembly with new set screws (permatexed) and place back in basket.
Basket.jpg
8) Per manual adjusted PTO lever gap to distance of matchbook cover.
When I hooked up the mower and ran her she worked flawless. I had totally service the 48" deck beforehand and this was probably the first light of day this baby had seen in over 20 years. No thrown belts...just a smooth cut and working clutch.