Nothing to it man. Take your prop off and set it aside.
You see the circle of bolts holding the center in the housing? Take ALL of those bolts out. The whole center pully, spingle, and bearing will come out as one piece.
From there you can see how it all goes together. We used to heat the bearing housing with a rose-bud torch beofre we pulled the bearling. Use an arbor press and press in a new bearing and seal or if its just the outside seal, you can just clean up the unit, get rid of the excess grease everywhere and tap in a new grease seal. I bet someone here will remember which way the shaft comes out even. Whether you really have to take it out to replace the seal or if the prop flange comes off and the new seal will simply slip in over the shaft. Havent looked at one since 96.
In general its just a big Tinker-Toy Not much hidden ya cant figure a way to get to.
Inspect the belt and if its not looking frayed or cracked just slap it back together.
Changing the belt is way harder than changing the bearing seal.
I think they have a diagram on their web site even, maybe hmmmm.
Check them at:
http://www.airboatdriveunits.com/ch2.htm
If not they got some pretty good pictures anyway.
Regardless once the top chunk is out you can see how it is assembeled and take it apart and reassemble from there.
If your not comfortable digging into it, then by all means send it to them and let them do it for ya.
Its a fine drive unit when used as dsigned.
Scotty
