The PO changed from the original stuffing box to a PSS seal on Cat’s Paw sometime between 1980 (when my father sold the boat to him) and 2004 (when I bought her back). That PSS did not have the vent tube option. There was some wear on the carbon(?) face (that seals to the SS part) although no drips I could tell, but I decided to replace the PSS with a new one in 2009. The new one has the vent tube. I routed the tube out into the left cockpit locker (always running upwards) and ran it up to just under the seat, so well above the waterline - have never used a bottle to collect overflow; if it occurs, it would just flow down into the bilge. The directions suggested sliding the SS part forward along the prop shaft to avoid continually compressing the rubber part of the seal, so I have done that each winter. Test it each spring (in the water) running at full speed to check for leaks and occasionally during the sailing season. Never saw any. Engine use is not heavy - probably 100-200 hours per season, so perhaps that helps explain why no leaks. But it certainly has worked well on Cat’s Paw.
Eric Frank Cat’s Paw, CC35 MkII, built in 1974 Mattapoisett, MA
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