# Wiring bilge pump.



## eightwt (May 11, 2017)

Am wiring up bilge pump. Its a 500 gph and has three wires, red, brown, and black. They show the red and brown going to the switch and the black as ground. I always thought black was hot, but in any case where should I ground it to? Thanks for any help.


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## Guest (Aug 20, 2018)

Ground will go to battery - terminal. I am guessing you’ve got an automatic pump that kicks on every so often on a internal timer. One wire will go to fused battery positive “probably red wire” other will go to switched power for manual over ride of auto feature. If you fish spooky fish, I’d reccomend a standard 2 wire pump and float switch install over the auto unit if that is indeed what you have! Those auto pumps are annoying at best!


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## topnative2 (Feb 22, 2009)

eightwt said:


> Am wiring up bilge pump. Its a 500 gph and has three wires, red, brown, and black. They show the red and brown going to the switch and the black as ground. I always thought black was hot, but in any case where should I ground it to? Thanks for any help.


black is hot for 120 household

red is hot for 12v


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## eightwt (May 11, 2017)

Yep its an automatic. Thanks for the reply's. Never messed with 12 volt, now makes sense.


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## Guest (Aug 20, 2018)

It’s gonna come on at exactly the point when a big fish turns towards your fly, when it does... big fish is gonna turn the other way! If the auto function isn’t a neccesity for you you can just tie that wire up and not use it. Or better yet, wire it to a double throw toggle switch and turn to auto when needed for over night docking ect...


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## Pudldux (Mar 3, 2016)

Not positive about the exact wire color,but you can just hook up two and the auto is the third wire just leave it capped. Then your only control is from the switch.


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## eightwt (May 11, 2017)

Thanks for suggestions. The toggle switch I have has 3 prongs. Says mom-off-mom on package. Is this a double throw? The boat is just a simple Whaler 13 that is covered when parked. Don't think automatic is absolutely necessary all the time.


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## eightwt (May 11, 2017)

Actually says (on)-off-(on) on the switch itself.


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## Guest (Aug 20, 2018)

Momentary would be spring loaded to center, in other words when you push up ir down the switch returns to off position. This won’t work for the auto function and you’ll have to hold the switch on when you need the pump on. Yes it is a double throw switch though.


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## FlyBy (Jul 12, 2013)

I like the Rule 27S that checks for water every three minutes, have them in both my boats. They will pump water at a lower level than one with a float switch. I do turn it off in the skiff when I'm poling.


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## eightwt (May 11, 2017)

It is momentary switch and the pump has a float switch.


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## Guest (Aug 20, 2018)

Swap the momentary for a standard on-off. Wire float switch to fused battery positive.


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## Vertigo (Jun 3, 2012)

Here's a good diagram for wiring a bilge pump...diagram stolen from an old Mako manual. The switch shown is built in to the OP's pump. The float switch can be wired as shown, or (as suggested) unused or wired into a 3-way switch. If your boat is kept in the water, wire as shown. If dry stored, block off the float switch or go with the 3-way.


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## eightwt (May 11, 2017)

Will do. Got to thinking about future navigational lights so will probably mount in a second switch, ideally that would hang under the wooden seat at the helm.


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