Forward Bilge pump float question

J

JohnL

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I have a 1990 24 Offshore, and my forward bilge pump works when I use the manual switch. However, when I lift the float switch, I hear it click but the pump doesn’t turn on.

My question is whether the float switch is wired in parallel with the manual switch. If so, I should be able to cut the two wires going to the float switch and touch them together on the switch side to see if the pump runs. If it does, that would indicate the float switch is the problem. If it doesn’t, then there may be a break somewhere in the wiring.
 
If the pump runs using the manual bilge pump switch all your wiring is good. The float switch is in parallel and all the wiring is right there at the pump. It is common for the wires to the pump to go bad over the years from sitting in bilge water. Test switch in installed orientation just in case it is old mercury type. I would just buy a new one, install it and properly crimp wires.
 
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The pumps two modes of operation are individually fed. The manual mode gets power from the accessory bus which is live when the battery switch is on.
The auto float mode on the other hand gets its power directly off of the battery, a separate wire to the battery with an inline fuse. This wiring is to insure that even with the battery switch off, the pump will still work if the float is activated.

Since your pump works in manual mode, it's ground is good as is its power source. The failure points are the float switch and wiring or the direct battery connection with inline fuse.. Float switches do fail but connection issues are more likely.
 
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seasick said:
The pumps two modes of operation are individually fed. The manual mode gets power from the accessory bus which is live when the battery switch is on.
The auto float mode on the other hand gets its power directly off of the battery, a separate wire to the battery with an inline fuse. This wiring is to insure that even with the battery switch off, the pump will still work if the float is activated.

Since your pump works in manual mode, it's ground is good as is its power source. The failure points are the float switch and wiring or the direct battery connection with inline fuse.. Float switches do fail but connection issues are more likely.
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Do you know where the float switch hooks up? It doesn't go into the pump.

John
 
"It clicks"... What clicks? Motor or float switch?

Yes, you can short the float switch wires together to test wiring.

Where does the switch hook up? Dude, it's over 3-1/2 decades old with who-knows-how-many-owners - there's no way we can tell you anything better that you can see for yourself.

But, what does your dash switch(s) look like? Is there an "Auto" position? That would be the power to the switch. Which, in my opinion, was always a stupid design... "Auto" shoudl work, well, automatically - one shouldn't have to select a switch position in order for "auto" to work. You can re-wire it.

These old boats are pretty simple and easy to work on.
 
Do a search for "ABYC wiring diagram for bilge pump" and wire as indicated. That way you eliminate all the previous jug-headed work.
 
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