How to Install a Washdown on a Boat
- 1). Research the correct deck washdown pump for your application. Manufacturers offer systems for different voltages and different water flow measured in gallons per minute, or GPM. Some pumps are designed to be installed in areas exposed to weather or damp locations.
- 2). Locate the manufacturer-recommended installation site. The manufacturer will have a maximum recommended distance from the thru-hull listed in the pump's installation guide.
- 3). Mount the pump using the recommended type and size screws. Many pumps are mounted with screws through rubber bushings mounted on the pump's frame. Do not mount the pump directly to the boat's hull. Mount a deck washdown pump either vertically or horizontally.
- 4). Plumb the pump to the thru-hull using the recommended size and type hose. Add an inline strainer if the thru-hull does not have a strainer. Use two hose clamps on each hose barb, and seal the threaded pipe connections using Teflon tape.
- 5). Wire the pump by connecting the pump's black wire to the boat's ground bus bar. If you use a switch to control the pump, connect the pump's positive lead to one side of the switch. Connect the other side of the switch to a circuit breaker with an amperage value recommended by the manufacturer.
- 6). Connect the water hose and nozzle to the washdown pump's output by screwing the garden hose-type fitting onto the pump.
- 7). Hold the spray nozzle open. Turn the pump on by turning the circuit breaker and switch to the "ON" position. Continue to hold the nozzle open until the pump primes and water flows through the nozzle. Close the nozzle to shut the pump off.
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