Not a novice job for beginners basically every thing that is attached to the drum has to come off, drum comes out then you split inner from outer, knock out the old bearing with a hammer and drift (lots of sweating at this stage)You
will need to assess if you need a new spider assembly, (if shaft has worn)you don't put new bearing on a worn shaft lastly if the bearing is seized in or the outer race is left inside the drum a new drum will be needed.weigh this up against the age of machine
repair will no longer be viable counting labour
wirecutterman, September 2008