Normal Water discharge is thru midsection, out gratings above and behind prop, so driveshaft will normally be wet.
Of course, driveshaft will likely be wet if waterpump is throwing water around midsection, versus pumping it properly into waterpipe.
Waterpump must be snugged down, where base is tight to gearcase casting, and gaskets above and below wearplate seal. If waterpump nuts are overtightened, the pump cover will crack. You did install heavy rubber slinger on top of waterpump cover, on driveshaft?
There is a small possibility that the gratings in the gearcase that allow water into pump are clogged. You might check them.
Of course, driveshaft will likely be wet if waterpump is throwing water around midsection, versus pumping it properly into waterpipe.
Waterpump must be snugged down, where base is tight to gearcase casting, and gaskets above and below wearplate seal. If waterpump nuts are overtightened, the pump cover will crack. You did install heavy rubber slinger on top of waterpump cover, on driveshaft?
There is a small possibility that the gratings in the gearcase that allow water into pump are clogged. You might check them.