Its hard to seal that gearcase. Pull the 3 screws on the cover plate. That exposes the other 7/16ths nut to remove the gearcase. Note round nut notched is the shift shaft actuator, note position on shaft & remove. Don’t lose. Now the lower will come off. REmove the driveshaft, gears, shaft & impeller. Heat the aluminum around the waterpump housing as it is glued into its home. No prying, something will break. Once the housing is off, you expose the driveshaft seal. The number of the seal is SKF 4912. Now the shift shaft seal is under the aluminum guide pipe. Be careful & wiggle the pipe loose from the housing. There you will find an O-ring . It’s 1:01 am now but I do have the prop shaft seal number somewhere in the shop. After getting all that done take a straight edge against the three threaded holes & check to see if the threads have been pulled out, Major place to leak because it causes a gap. Next get some blood pressure cuff hose & once the lower is ready slide it down over the shift shaft & on the top of the gearcase. Let it extend past the small round opening of the top. When you tighten the cover on it will compress on the opening & make a “home made” extra shift shaft seal.
Any questions ? jeff.50@cox.net. Not as hard to do as thought.
Edit: I made my own gearcase gasket using the housing & a copy machine. Just fit the inside & when installed use a razor knife to cut the outside after it’s on. Don’t use your scanner, it changes the dimensions.
