When I grease the shaft the grease comes right out of the bearing at the bottom, I don't think this is normal and I need to find a new bearing for it. Its a 31hp beavertail, 2006 I believe. Also, how do you replace them?

sounds like your seals are shot call BT and get seals and bearings replacement is remove prop and jam nut ,loosen set , remove bearing and seal case, nock out seals replace as removed same with bearings and reassemble in reverse order as you took it apart and then and grease but pump grease to the point of preasure on grease gun you dont want the grease to push out of the seals causes the seals to fail quicker