On a 41P the input shaft bearing are sealed, so for the water to get into the flywheel area, you most likely have had a bellows leak for a while.
If you have run on the starter gear, you have a leak. The starter can easily be fixed by disassembling and greasing.......I would also remove the bellows and inspect.
You might also need bearings and seals for the shaft and a u-joint....I needed a housing also......