I actually figure that the stripped piston is a result of the last tooth (the metal one at the head end of the piston) failed. It looks in tact in the pic i posted and it actually is but it is broken off of the rack and if you put pressure on it it will lay out almost flat and press into the piston allowing the piston to slip forward befor the sector is finished its cycle so the last tooth of the sector would drag along the piston a bit stripping those gears.
Aoe was good piston, not so much lol
Edit if you look closely at the front of the metal tooth you can see the crack and if you wher to push on the metal tooth it wobbles and will lay out flat if pushed towards the other teeth
