That thread that the nut screws onto has a cut along it`s length, as the nut tightens up, the threaded "collar" clamps down on the output shaft. By all means use a puller, I have used a piece of hard wood to tap the threaded collar and that usually separates the collar from the shaft - remember that the parts of the clutch are cast steel (machined down), so tread carfully.
NB the spring inside the SB33 clutch is longer than the SB45. The bearings on the roller, ect are the same as SB45`s bearings
(I purchase a kit of bearings for SB45 to rebuild my SB33. I like the SB33 because it is a part of the history of Scott Bonner and I enjoy restoring old machinery.
I have just purchased a Bon Mow 19 (cira 1950`s) as the next project.
