dripless seal

It’s about keeping you underway rather than underwater. If you’ve got an inboard motor (or two) keeping tabs on your stuffing box is critical. Every season we’ll grab a few new lines, a couple of new fenders, maybe a life jacket and a crab pot. Heck, it might be the year you haul out for new bottom paint and zincs.  Might be a good idea to look at your stuffing box.

Why is this important to know? Well, a stuffing box is what prevents your boat from flooding and eventually sinking.  There are primarily three variations of the stuffing box; rigid, flexible stuffing box, and flexible (dripless) seal.

Traditional stuffing boxes have a tube slightly larger than your prop shaft. It also includes a “gland nut” or packing that is threaded on the previously mentioned tubing. Because these parts rotate frequently during use, traditional stuffing boxes a few times per minute while in use and should be adjusted or at the very least, inspected on completion of your trip. If your stuffing box is producing a steady drip even at dockside, it’s a good time to get it serviced.

Dripless seals are face seals with flexible bellows attached to your stuffing box collar. In turn, this presses the flange, (often made of carbon or graphite) against rotating stainless rotors, which spins with your prop shaft. Finally, this establishes the seal between your rotor and flange.

While your stuffing box may serve you many years without incident, a stuffing box failure, along with an inadequate or inoperable bilge pump can produce the optimal conditions that could quickly sink your boat.

One way of providing an increased life for your stuffing box is to inspect it at regular intervals. While the repair and maintenance might seem straightforward, each boat’s individual access to shafts and seals ultimately determines the degree of frustration (or satisfaction) of the repair experience. If you’ve owned a boat for more than fifteen minutes, you are probably well-aware of that fact.   If you have any trouble or elect to not do the work yourself, check out Semiahmoo Marina’s Business Directory under Marine Services. I’m sure one of these fine craftsmen will be able to bring your dripping shafts back to dripless in short order. Stay safe!



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Your boat’s stuffing box: What you don’t know could sink you — No Comments

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