Keep Your Bilge Dry with a Garboard Drain Plug

The owner of this boat has gone one better and installed a length of threaded pipe with an elbow on the end into his garboard drain to keep dripping water from eroding his bottom paint

Every once in a while you hear about a boat stored ashore that leaked enough rainwater to fill the bilge and flood the cabin. What a mess! And even a little water in the bilge, if it freezes, can cause damage. Boats that are frequently stored on the hard can benefit by having a drain hole at the bilge’s low point. This is called a garboard drain, a carryover from the days of wood boats when the garboard strake or plank marked the turn of the hull where it met the keel.

Various companies make garboard drain plugs, basically threaded bronze fittings that securely plug a drain hole when the boat is afloat and can be opened when it’s on the hard to let out rainwater. It’s better to go for one where both the flange fitting and the plug are bronze. Some are a mix of brass and bronze. To install the fitting, simply drill a pilot hole, angled slightly downward, through the hull’s side at the lowest point in the bilge. After that, use a hole saw the same diameter as the stem on your garboard drain—depending on the maker, this will be up to 1 1/8in—to cut the hole proper. Be sure to seal the edges of the hole with epoxy resin. There are various ways of installing the drain plug, depending on the type. I used epoxy resin on mine.

You can place a small screen over the open hole to prevent pests frvom entering and colonizing your bilge while you’re away. A stainless steel household kitchen sink drain screen, sold in hardware stores, is perfect for this.

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