The description of the problem is unfortunately not clear enough to understand.
In many boat designs where the gearbox
is some distance from the propeller
; You will find a pipe which has a larger diameter than the propeller shaft. This pipe is called a log (they used to be made of wood). The pipe may be loose or fixed. The aft end of the pipe, at the point where it exits the hull will contain a cutlass bearing
(about 3 inches long, but it's internal diameter is only a few thousands of an inch bigger than the diameter of the prp shaft) which allows the prop shaft to spin in it and at the same time it allows water to travel the full length of this pipe - right up to the stuffing box which prevent the water traveling any further.
In most modern boats, the shaft log is not really a "log", but a metal casting or machined part that fits over the propeller shaft hole on the inside of the boat. The stuffing box, which is similar to a water pump packing gland
, fits around the shaft and clamps to the shaft log.
So, EXACTLY where are you finding water leaking from??
of Cutlass bearing below :-