How to Wire a Bilge Pump

Step-by-Step Guide

1. 1

   Step 1: Mount the bilge pump securely in the bilge.

   Unrestrained bilge pumps can fall over, intake air and become damaged.
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   Step 2: Fasten the bilge pump with brackets or use epoxy to attach bolts to the bilge bottom

   ,, Hoses sold with a corrugated interior can reduce water output by as much as 30 percent. , Bends and additional hosing also contribute to reduced bilge output, so when you wire a bilge pump, the hose should be both short and straight. , A submerged discharge will siphon from the surrounding water into the bilge only to have the bilge pump eject it again.
   
   This cycle continues until the battery is exhausted. ,,, Always check the literature which came with your pump for suggested wire size and allowable distance.
   
   You may also attempt to contact the manufacturer for a suggested wire size should you be unable to determine the wire size on your own.
   
   It is recommended by the ABYC that the voltage drop be less than 3% for this wire run so the use of a voltage drop calculator and ABYC Wire Size Table can help ensure your wire is appropriate to the specifications of your pump and boat.
   
   Voltage Drop Calculator and ABYC Wire Size Table , Waterproof these connections using heat shrink tubing. , Be certain the bilge does not contain any flammable fumes before administering the heat. , When wiring a bilge pump, do not go through the distribution panel.
   
   Even when the boat power is off, the bilge pump should still be able to receive power. ,,, Do not strip the wires first. ,, This allows you the freedom to select off, on or automatic.
3. 3

   Step 3: which then serve as mounting studs.

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   Step 4: Mount the float switch.

5. 5

   Step 5: Connect the pump to the discharge using a hose with a smooth interior.

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   Step 6: Use as little a hose as possible to make the hose line from the discharge to the pump as straight as possible.

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   Step 7: Place or mount the discharge well above the water line.

8. 8

   Step 8: Lead bilge pump wiring up and out of the bilge in a timely manner.

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   Step 9: Secure wiring so it does not sag or come in contact with the bilge water.

10. 10

    Step 10: Use adequately sized wiring for the bilge pump.

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    Step 11: Use crimp-on butt connectors between the pump leads and supply wires.

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    Step 12: Center the tubing over the butt connectors and apply adequate heat to shrink the tubing.

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    Step 13: Connect the bilge pump directly to the battery.

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    Step 14: Install a fuse in the positive wire very close to the battery.

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    Step 15: If your 3-way switch panel does not come with a fuse

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    Step 16: this must be attached using another crimp-on butt connector.

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    Step 17: Loop supply wires under the battery's terminal wing nuts.

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    Step 18: Install crimp-on ring terminals followed by a copper washer between the ring terminal and the wing nut.

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    Step 19: Wire your float switch to your 3-way switch.

Detailed Guide

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