93 300 Bayou

I have been working on my 93 300 bayou, first the nut that holds the disc on came loose and when I took it apart and found it, rethreaded the shaft, put all back together and started it up , I can see it move just a little when put in gear but will not move forward or reverse! Where do I start and what adjustments are needed??? I am referring/shaft to the nut that holds disks to atv.( 92015


NUT,16MM


92015-1465) in parts diagram