Hi Salty, Sorry I had to move your post, but the previous post to yours is still an on-going repair and it affects the archival value of Jeremy's thread.
Now to your prob; Grumpy is quite correct, someone has had a prob with the captive cotter in the inner clutch half and removed it....and then in error, drilled the hole right through and thought this will fix the prob. Unfortunately, it will not.
That inner clutch half has now run its race and kissed its chips; it needs to be replaced with a new one which will have the grub screws placed (one over the engine PTO key) and one 90 degrees opposed to it. Don't forget also that the cutter clutch should be in balance; otherwise vibration will cause further damage.
This is a better fixing method than the captive cotter....and will allow you to adjust the cutter clutch perfectly.
If you agree, I will step you through the procedure to remove the engine, separate the clutch halves and repair it.
