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Bilge wiring


New boat to me....2015 model.   

I think there are 2 bilge pumps.   one midship and one aft.    The switch at the dash does nothing, meaning nothin comes on when it is on.    but I do know the midship pump is working as I saw it pump water out.
I took the aft pump out to diagnose and direct connected it to the battery.   the pump came on and appeared to be working properly.   The float switch does not work. 
fuse appears fine it did not pop out.

I searched for another fuse but cannot find any other fuse for the aft bilge
So Im confused....   

If the pump works, why doesn't it come on when I manually hit the switch on the panel?   could the float switch be the culprit?   I'm not sure why the float switch would not be allowing the manual switch at the helm to not work, but I'm out of ideas.   Unless I have a bad helm switch?    


  • cjjjdeck
    cjjjdeck Member, Moderator Posts: 1,872 ✭✭✭✭
    You are correct, you have 2 bilge pumps on your model.  Here's the setup for your boat:

    Power for bilge pumps come directly off the battery and use a brown wire.  This circuit is protected by an inline fuse or circuit breaker located near the battery connection (usually 5 amp rating).  I am not sure if both pumps run off of the same wire or if there are separate wiring for each pump.  You will easily be able to tell when you look at the battery connections.  I do know that the mid-ship bilge pump is wired to only operate with it's float switch, not with the helm mounted switch (so no manual operation).  Only the aft bilge pump works off of the helm switch.  The bilge pump circuit is protected in two places for the aft pump, the inline fuse/breaker and the helm mounted circuit breaker switch, and the inline fuse/breaker for the mid-ship pump.

    Below are some graphics you may find helpful, a picture of what the pump/float switch probably looks like and a simple wiring diagram of the bilge pump circuit:

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