Prop shaft/ rear seal leak

[Pleal]

I recently bought a 1984 Hunter 31 with a Yanmar 2GM engine (not sure of the drive model). I got a great deal on the boat, because it is in "less than perfect" condition. I recently had a very dirty bottom cleaned, and afterwards, it developed a leak under the aft end of the prop seal. I also have a small leak from the stuffing box, which I'm less concerned about (I can fix that). The previous owner obviously had issues with this area before, because it appears they used close to a full tube of caulk all around this area. I cut some of the caulk away from the hull bottom and cleaned, scuffed up & applied some pool 2-part underwater epoxy to try to stop or slow the water flow. I did slow it some, but it is still leaking. I also replaced the hose clamps that weren't encased in caulk. I know I will have to haul her out soon, and will inspect and repair everything below the waterline, but I'm looking for some more ideas prior to the time I can get into a yard.

[Bill O]

Having a difficult time picturing exactly what you mean when you say you have "a leak under the aft end of the prop seal".
Is it the hose coming off the thru hull going to the stuffing box that is leaking? (If not, could you show us a pic of the leak). If it is the rubber hose, would take it apart during a haul out and inspect the thru hull and hose. This hose is typically a small section of exhaust hose and would replace it. It is more of a pita to do this and why the PO probably put a tube of caulk on it instead of doing it correctly.
In general, you will need to uncouple the shaft from the motor, remove the coupler, then push the shaft back enough to slide the stuffing box and hose off the forward end of the shaft. Measure the thru hull carefully to purchase the correct size rubber exhaust hose. Can change the stuffing box packing and replace the hose clamps w/good quality SS clamps at this time also.

While you are at it, you may as well change the cutlass bearing and then you are done for a while.

[Orion Jim]

https://marinehowto.com/re-packing-a...-stuffing-box/
This link is a valuable resource. Please do not use exhaust hose as stuffing box hose is readily available and is the correct component for this application as it is much more robust, as noted in the link above.

[Bill O]

Yes, should have mentioned the type of heavy duty exhaust hose we have on our Lasdrop (dripless) shaft seal.
https://tridentmarine.com/product/tr...-water-202v-2/

[SailingHarmonie]

It is hard to be sure based on your description, but it sounds like you may have a cracked stern tube (the piece of the hull the packing gland is clamped to. Alternatively, the rubber hose that connects the packing gland to the stern tube may have failed.

In either of those cases the diagnosis is: Your boat is sinking.

Granted it is sinking very slowly at the moment, but that could change at any time. If it was my boat it would be in the nearest travel-lift TODAY. Not tomorrow, not next week, not when convenient.