Combines knife drive problems

Some sort of hammering is causing this to happen, I suspect. The bearing behind this snap ring may require loctite to keep it from moving inside the wobble housing and putting pressure on the snap ring. Check over the cutterbar as well - must be in excellent working order to prevent hard driving. Double check all cutterbar,stabilizer and wobblebox mounts - any play here is unacceptable and may cause hammering. Are your parts assembled in the correct sequenceIJ Hope that this helps.

think i may have solved it shaft gets wear in it and lets bearing move about solution purchase new shaft from agco $1281aussie dollars none around 2nd hand installed new shaft and bearing loctited the bearing on showed shaft to a couple of machinsts and asked could they build up and machine 1 laughed uncontrollably

Yes, I could just imagine trying to jig that thing in a lathe to remachine it. Trouble is, they machined it somehow in the first place. I had to replace this shaft in a customers box this summer - same deal, but found second hand (Canada).