Prop shaft - stuffing seal?

[Plum76]

Hello, new owner here. Quick question the the outermost stuffing box seal, the last one before the bilge. Mine has popped out, likely due to too much grease I’m assuming. Can I just press it back in if it’s not damaged, or do I need to source a replacement?

If I do need to replace, do I need to address all the packing in the rest of the assembly as well, or is it a might-as-well situation? It wasn’t leaking excessively before, and it just came out on the way to the trailer for winterizing..

Thanks.

Jason

[dkirsop]

From your description it sounds like you have an A25 with the original shaft seal. Yes, you can just push the seal back in if you are careful and avoid damaging the lip. I keep a piece of 3/4" plywood with a slot cut into it that slips over my shaft for this purpose. The seal will press out if too much grease is put in or it over heats. Just a small dab of grease on your finger is about all that is needed for a season of use. Note there are two seals present on this fitting - one fore and one aft. When correctly fitted to the shaft log there should be about a 3mm gap between the end of the shaft log and the rear seal. The shaft log acts as a retainer to stop the rear seal from popping out.

When re-launching your boat you should loosen the rear hose clamps on the seal and flex the hose until water begins to drip freely. Then re-tighten the clamps. This removes air from the shaft log and prevents over-heating of the seal from shaft friction.

[Plum76]

Thank you, that’s what I needed to know. Correct on boat ID, 1970 (or 71 per title) A25 deluxe, running the original AD21 (rebuilt).

Thanks much.

Jason

[DesertAlbin736]

I have the same vintage 1971 A25, except re-powered with a Yanmar, with what probably is the original conventional stuffing box, which I assume yours is too. In fact, re-packing the stuffing box is on this year's PM list. I use this stuff from Defender (available elsewhere too I'm sure)

flaxpack.jpg

https://www.defender.com/product.jsp?pa ... &id=995213

Whichever type of packing material you use, here's a good primer on the "science" of traditional stuffing box packing. Thanks for posting your question, I just learned some new things here.

https://marinehowto.com/re-packing-a-tr ... ffing-box/

[Plum76]

Great reference there. I’ll probably pull my box apart, not knowing the history of how long it’s been in service and what condition it is. Good to check before I try to put too many hours into it.

Jason