Easy deal if it is a standard gear model ( non SOS )
1, drain rear/hyd oil
2, put pto selectro into gear
3, remove 4 bolts holding pto bearing carrier in
4, slide it out. if it is hard to pull.. put a drift or screwdriver thru the hole in the shaft to yank on.. can also take a hammer and hit the flange to spin it int he housing so it will break the rust and gasket bond. DO have a new gasket and pto seal on hand. you MAY need a new wear ring or bearing. but those usually last longer than the seals... and the new seal is a different size thant he old one by some small dimension.. so the lip generally rides in a slightly different location anyway.. ps.. lip / open side toward the oil.. the old seal will likely be a closed back seal too.
5, use a small screwdriver or a pair of trivers to pop the split ring edge out of the groove, and then walk it around and out of the groove using 2 screwdrivers. this is the ring in back of the bearing inner section of the pto shaft. the ring is a bit of a booger with tapered ends.. but once you get an end up and pressed over you walk it out like beading or debeading a tire with 2 irons.
6, lay a piece of wood on the floor, grasp pto shaft by the long inner end and tap the short outter stub end down onto the wood.. the bearing carrier and seal assy should drop off, leaving the pto shaft and wear ring and bearing assy in your hand.
7, inspect the bearing for play and the wear ring. sometimes the wear ring slips and allows bearing walking. there are retainer rings ont he shaft holding the back of the bearing... make sure they are in place. occasionally you find rings leaving wear marks floating out on the shaft. if the shaft and bearing and wear sleeve are goot, set it aside, and look at the pto seal and bearing carrier.
8, using a seal driver or large socket, drive the old seal out the back, and clean up the housing and seat the new seal in to the front split ring. grease the lip, now set the bearing carrier and new seal on top of the shaft and bearing assy, line it up by hand, grease the wear sleeve and bearing, now tap the long end of the pto shaft down on the wood, and the bearing carrier and seal will seat onto the wear sleeve and bearing... hold it together, carry it to your vice, open jaws and lower external stub end in till it is fully seated into vice and bearing carrier can't go anywhere, tighten jaws on stub end.. now slip that split ring over the top of th shaft end and walk it into the groove behind the bearing.
9, clean her up to remove debris, clean gasket surface on flange and housing with razor to remove all old gasket, etc, solvent.. etc. install new gasket dry, or with a smear of permatex if you feelt he need, slip back in spinning it by hand if it needs help to line up. line up gasket. install 4 bolts.
10, refill with oil..
done.
