Re: 1981 omc stringer 800 tilt clutch
In addition to what full stringer said, I would also go so far as to remove the tilt shaft(#46) and all associated components and inspect them. Follow the exploded diagram to make sure everything is accounted for and not chewed up from wear. Also, make sure you have a new nylon washer(#43) as this is a common water intrusion point when old washers are used. Also, make sure you use two gaskets(#66) instead of one so that when you seal the assembly back up you dont inadvertently crank down on the mounting bolts(#38) and bind the clutch pack so that the whole assembly cant rotate.
Get yourself the Seloc manual, at the least, or preferably the OEM manual so that you know exactly how to take everything apart. It is very simple to do with basic tools but the manual will keep the order of assembly/disassembly for you.