chris wrote:
Changed my impeller today, and when removing the lower unit, I noticed
that I had a slight oil leak from the upper shift shaft that was running
down the shift shaft to where the lower and upper shift shafts come
together. And then unceremonially dripping to the floor.

Can someone tell me if there is supposed to be oil anywhere near the
upper shift shaft? I know it shouldn't be leaking but I'm concerned that
it points to a bigger problem like oil in the exhaust bellow? I'm having
a hard time visualizing where outdrive oil bathes the upper shift shaft
to allow for this type of leak. Anyone with insight of the oil cavities
inside of a mercruiser pre-alpha drive?

I can't visualize it either.
There are two seals on the vertical drive shaft in the upper unit that
could be leaking. There is a shift shaft seal in the lower unit. There
are 2 seals in the water pump base. If the bellows leak oil you have 2
problems. The bellows itself and the yoke seal.