How to Wire a Three-Way Bilge Pump
- 1). Connect the bilge pump's black wire to the negative battery terminal. If necessary, extend the wire using a butt connector and length of wire. Strip back the ends of both wires using a wire stripper. Crimp the butt connector with a wire crimping tool. Slide a piece of heat shrink over the butt connector, and apply a heat gun. Remove the wing nut off the battery's negative cable. Crimp a ring connector to the end of the wire. Install the wire onto the negative battery terminal. Reinstall and tighten the wing nut on the terminal.
- 2). Connect the bilge pump's brown wire to the three-way switch terminal labeled "pump." Extend the wire with a butt connector and length of wire. Apply heat shrink over the butt connector.
- 3). Wire the float switch to the three-way switch. Extend both float switch wires. Connect one wire to the terminal marked "auto." Connect the other wire to the terminal marked "pump."
- 4). Connect a wire from the three-way switch's "battery" terminal to a fuse holder. Connect the fuse holder to the positive battery terminal. Insert a properly rated fuse per the pump instructions' guidelines.
- 5). Test the bilge pump. Briefly set the three-way switch to the "On" position. The bilge pump should now be running. Set the switch to the "auto" position. Lift the float switch. The bilge pump should turn on when the float switch is lifted and shut off when the float is lowered.
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