Sinking? Check Your Stuffing Box

It's normal for a traditional stuffing box to have a slight drip when properly maintained, but in this case for a 1978 Catalina 30, lack of maintenance led to a seal failure and rapid water intake.

Anatomy of a old-style dripping stuffing box: Starting at the prop and moving forward we see the principal components of a somewhat complex and mission critical system. The zinc annode. The cutless bearing at the through-hull, which keeps the prop staff centered, true and friction free. The shaft log, through which passes the prop shaft. A quadruple-clamped hose, first line of defense in keeping seawater out. The packing nut at the extreme inboard end of the drive train is the essence of the system. It's stuffed with felt packing material that expands when wet and blocks seawater from coming into the boat. It needs to drip, which tells you the felt packing is wet and therefore doing its job. Illustration by Bruce Bingham.

Sometimes as a sailor you are learning to run before you can walk or even crawl. If the auto bilge pump isn’t working, maybe it’s faulty wiring or is it clogged? The seawater pump slowly drips and that leads you down a road of a possible impeller repair. And sometimes as a sailor it takes almost sinking to learn one important message “Check your stuffing box!” Wait. Let me rephrase this “LEARN what and where your stuffing box is!”

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Kimberly Saylor
I am a recreational sailor of an old boat! I was introduced to sailing at a young age and now spend my time sailing on the Hudson River, N.Y. and taking care of our 1978 Catalina 30 “Rock Steady” which has been in my family since the mid 1990’s. I live in Northern New Jersey and when I am not working or spending time with my family, I am working on or thinking about boat projects and learning as I go.


  1. Well that sounds like a harrowing experience. Good old dad to the rescue. 🙂 We sail the same waters. Always comforting seeing many SeaTow and TowBoat US vessels in the area.

    It’s my understanding that with a dripless shaft seal, you don’t have a traditional stuffing box anymore. Seal and connections still need to be checked, but there’s no flax, or need to burp the seal for proper lubrication with a dripless. At least that’s what they told me, as I have a Tides Marine dripless that recently needed replacing.

  2. Thanks Brian for your comments! Nice to see you also sail the same waters too. I am also under the same impression with the dripless. I don’t think anything is truly maintenance free but just a different configuration that requires differing types of checks. So far ours has been okay, but then again you never know 😀. Sail on!