Everything orderly devolves into chaos. That’s the principle of entropy. Mountains tumble, ravines fill up, walls collapse. And a sailor’s feet will eventually get wet. The hull, deck, and coachhouse of your boat—although conceived intelligently, built thoughtfully, and maintained lovingly—will admit water at some time, be it a drip directly over your bunk or a torrent into the bilge. Boaters accept this predestination and prepare cleverly for it: The prudent mariner is ready at any time to pump ship.
Since the Pharaohs floated upon the Nile and before, sailors have spoken this truism in many languages: “The best bilge pump is a scared man and a bucket.” A stout bucket, worked desperately, can shift a mighty amount of water.
Our best advice features no high technology: seize a large-volume container and pitch water out—through a hatch, into a self-draining cockpit, or over the side. Know where that bucket is and how you plan to use it. It’s the cheapest and most efficient water expeller you can have, and you can use it to wash dishes and decks, too. Two buckets and two crew members, sufficiently motivated by water coming, say, through a collision rift in the hull, are even better.
An oak or cedar bucket with a rope bail is a traditional tool aboard wooden boats, and much-praised by L. Francis Herreshoff. It floats, it works, it’s handsome. The palm-and-needle stitched canvas bucket, with or without a wooden base, is even more traditional, a part of Hervey Garrett Smith’s marlinespike craft. Boaters may not be familiar with the black rubber horse-stall bucket but can appreciate its easy price and its refusal to scratch woodwork.
The bailers shown here are traditional for small boats and modest sailing craft. The exotic example from the South Pacific is an illustration of art transforming a working essential to a beautiful object, perhaps to soften a disagreeable chore. The leather-and-wood bailer, and its even simpler carved brother, were familiar tools in the ships VASA and MARY ROSE five hundred years ago. Any of the three examples would be welcome in bailing an open boat today.
Some leaks are catastrophic, some are nuisances. Getting started in boats most often involves small, open daysailers where only a few gallons of water will wet your bottom. Simple mechanical pumps, probably like those used by the Pharaoh’s bargemaster, are appropriate and even satisfying: Sending rot-inducing rainwater overboard with a hand pump feels like progress. WoodenBoat has detailed a few basic wooden pumps you might make in your shop (WB Nos. 178 and 243). They utilize leather one-way flap valves at the bottom, and push-rod “lifters.” Water is lifted up through an opening flap-valve, then out the spout on the up-stroke, but the flexing downstroke against the one-way flap doesn’t affect the column of water. That’s all there is to it, and the same principle applies to the familiar water pump in young America’s kitchens, and to the galvanized steel and the brass lift pumps used in boats throughout the past century. The logistics of a small flume carrying the lifted bilgewater from the lift pump to the gunwales is plain: pick up water from the deepest boat recesses and carry it overboard.
Even without a mechanical pump you can bail your boat. What’s wanted is a flexible lip that will conform to the curves of your boat and a capacious gatherer of water. Plenty of commercial bailers are sold, like the ones on the left, but many boaters prefer to fall back on recycling detergent, milk, or bleach bottles. True, we may refer to fiberglass boats as “Clorox bottles,” but we respect the watertight integrity of a Clorox bottle.
All “craft” bailers are works in progress. You’re not spending money or much time on them, so you’re at leisure to experiment. Mark a likely scoop contour that will leave good bilgewater volume in the bailer, and cut away with a utility knife with a new blade. Friction-tape the top closed. Does it work perfectly? If not, then try another.
Permanently Installed Pump Types
Getting started in boats may involve a small cruising vessel sleeping on a mooring, vulnerable to leaks. Such a boat might need to be pumped out each time you arrive aboard, and a hand-stroked diaphragm pump might be the tool of choice for this. Pumps of this type are rugged and move a lot of water, and they are also standard equipment in bluewater boats: Keeping up with a leak at sea may well depend upon such a permanently installed diaphragm pump with a handle convenient to the helm. This pump is not much more involved than the lift-pumps. It consists of two one-way valves and a rubber diaphragm that expands and compresses to squeeze a volume of water through the pump.
When your boat is alone for many days, or when a seaway promotes “working” of the hull and admits a bit more water, accumulation in the bilge can be addressed by an electric bilge pump. This is well-established technology. The typical arrangement consists of a plastic-bodied pump with a hard-plastic impeller in its base, an electric switch, and a discharge hose leading to a through-hull fitting. The electric switch is activated when it floats in rising bilgewater to beyond the horizontal position. There are many contemporary variations on the basic, time-honored unit shown here. Some of them have switches built right into the pumps. Others dispense with the float switch altogether, and instead “sample” the situation at specified intervals; if water resistance is felt, then the pump will keep on running. The most recent variation on the switch-and-pump theme includes a low-profile pump body and foot (the portion that picks up water) that can be configured for a variety of tight situations.
A multipurpose “impeller” pump can also be used as a bilge pump. The advantage of this type of setup is that the pump itself can be mounted anywhere, thus keeping the electric motor out of the harsh bilgewater. The pump body may be mounted on a convenient bulkhead, with a pickup hose equipped with a foot valve extending from it into the depths of the bilge. A separate discharge hose leads from the pump to a through-hull fitting. This style of pump has a many-armed rubber impeller set into a housing slightly smaller than its unconfined diameter. Its spin-axis is offset from the housing’s center. Each time the impeller revolves, the inter-arm spaces on one side are being reduced, and the spaces opposite are expanding. Water is drawn into the pump by the expanding spaces, then pushed out by the compressed spaces. There are alternative geometries for impellers, but they all depend upon the longevity of the impeller, flexing many times per second.
The prudent mariner replaces his impeller each season, and always keeps a spare one aboard, along with the tools to replace it.
Bilge Pump Installation
The “plumbing” of pumps is straightforward, but be wary of fluid dynamics. An improperly plumbed pump can actually siphon water back into the boat, potentially sinking it.
Pumps are connected to smooth hoses sized to fit the output and corresponding through-hull fitting. Corrugated hoses, though sometimes used, create a friction that reduces the efficiency of your pumps. The connections are force-fit and then secured by stainless-steel hose clamps—two of them for each connection. All this good advice means little if you don’t get into the bilge and inspect those hoses and their clamps several times a season.
We’re showing a dual-pump configuration. The American Boat and Yacht Council (ABYC; www.abycinc.org) recommends that the discharge in a powerboat be above the waterline when the boat is heeled 7 degrees. In a sailboat, the ABYC recommends that the discharge be located at or above the maximum heeled waterline—unless there’s a seacock installed on the discharge through-hull fitting, and there’s a vented riser loop, as shown here, extending well above the waterline as a guard against the aforementioned back-siphoning. The seacock-and-vented loop option is best.
For aesthetic reasons, many people locate their discharge at or near the waterline—with corresponding riser loops to prevent siphoning. Plumbing configurations will vary from boat to boat, due to the constraints of shape, layout, and structure. The ABYC has a thick book of carefully considered standards for all manner of boat systems. If you are altering or installing a bilge pump, we highly recommend a review of these standards before designing your system; there’s more to it than we can detail in this short article. Do not neglect to attach a conical wooden emergency plug to the through-hull fitting; it might save the boat in the event of a hose failure.
Electricity at sea is always suspect. The bilge environment is not ideal for electronic integrity. Do what you can to forestall failure by using good tinned-copper marine wire, and marine-grade electrical connectors coated with heat-shrinkable plastic. Run the wire out of likely
bilgewater or splash. Use a non-conducting clamp to secure every wire at intervals of, at most, 18″. Connections should be robust, positive, and water-resistant. (Again: consult the ABYC standards before getting too deep into your design.)
Dual Bilge Pumps
It’s difficult to judge the scale of a leak immediately. A small bilge pump, set to work by a float switch, will deal with nuisance water. But if the water level in your cruising boat rises above this maintenance pump, you may be in trouble. Many cruisers address this eventuality with a larger, higher-volume pump and a second float switch, and some install both a warning light and a very loud alarm to alert the whole harbor if the boat begins taking water seriously.
Because every pump should be inspected several times per season, a two-pump array with its two-stage float switches can be mounted on a single marine plywood plate that slips into guides on the boat’s structure—say, a floor timber. The plate, pumps, and switches are “plumbed in” and electrically connected with enough slack to pull and inspect or repair the entire system as a unit. The board, when in use, must be securely fixed in place, and this can be done in a variety of ways: turn-buttons, screws, bolts, or even Velcro. The solutions will vary from boat to boat.