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Bilge pump wiring question

Old 09-22-2018, 07:23 AM
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Default Bilge pump wiring question

I am in the process of re wiring my batteries, and would like my bilge pump to have power when i leave the dock and turn my battery switch off. It is currently wired the way it was from the factory.

I am thinking about running a wire from the battery, up to the helm switch (on/auto/off). So i would disconnect the power being fed from the bus bar to the switch in the helm, and replace it with a wire run straight from the battery. I would put an inline fuse in the wire from the battery. Have to see how many amps the pump draws and fuse accordingly.

Does anyone see any problem with this?
Old 09-22-2018, 07:43 AM
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The correct way is a fused wire from the battery to the switch, than to the pump.
Old 09-22-2018, 08:06 AM
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I don't know what kind of boat you have but most boat are already wired that way from the factory.
Old 09-22-2018, 08:26 AM
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2010 Carolina skiff Sea chaser 2400 wa.

Right now it is wired just like all the other switches. It has the one hot wire jumping from switch to switch. But that hot runs from the hot bus bar, which would mean the bilge pump would turn off along with the rest of the house power when i flip the switch to off.

I purchased it used, and was surprised by this my self. Pretty easy fix.
Old 09-22-2018, 08:44 AM
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Why run the automatic through a switch? It’s just another point of failure. If you go through a switch mark it clearly. It’s hard to remember which way is auto and which way is manual.
Old 09-22-2018, 09:47 AM
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The dash switch might only be the manual switch. (Which won't work with switch off). Often the float is wired direct to battery. Turn the battery switch off and lift the float switch to test.
Old 09-22-2018, 01:47 PM
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Tried pulling the float up with the battery switch off... nothing. Wired it like explained above for now and its working with the battery switch off. Center on the switch is AUTO, up is ON, and down is OFF. I agree that it is one more thing to fail, or accidentally push the button in the wrong position before leaving.. but for now i am going to go with it. When i pull the boat next month I will work on it in my driveway.
Thanks for the help
Old 09-22-2018, 03:23 PM
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For a schematic diagram of bilge or sump pump wiring with a float switch and a manual switch, see

Classic Whaler: Boston Whaler: Reference: Bilge Pump
Old 09-22-2018, 06:09 PM
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U need to power the bilge switch with its own wire. U can run it from the hot side of the main on-off switch. Put a switch on that wire so you can turn off the power when on the trailer.

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