Manual Bilge Pump Switch Not Working When Auto Float Wire Connected

[kibbs]

Replaced a bad Bilge pump that had an integrated float with a new one. It has 3 wires; brown, black and red. The old owner of tbe boat did not have the power for the auto float (red) connected at all. Just the black and brown wires. The switch in our boat at the helm is only off or manual. The manual position activates the pump fine now....IF I don't have the red wire (fused) connected to the battery. If I connect the red wire to the battery then the helm swith light come on when I flick it to manual, but the pump will not start. I have confirmed that the pump works in Auto mode when connected direct to the battery by turning the unit upside down to power up. So I'm confused as to why the helm switch can't run the pump unless I disconnect the red wire from the battery that powers the auto float.

I have spent hours looking for an answer to this scenario so any help is appreciated.

 

[nola mike]

I think you need a 3 way switch. Either circuit can be closed, but not both. Any idea what pump you have?

 

[kibbs]

I've read alot about NOT using a 3way because its so easy to leave it in the off position. Seems the largest consensus I can find says the 2 way (manual/auto) switch with a direct wire of the red wire to the starter battery is pretty fool proof. Even my boat mechanic wires them that way. Now if the boat was bigger and had the 3way already then yes thats when its wired to a switch...but I think my way is very common...unless I completely missed the mark.

Its a shoreline pump.

 

[nola mike]

I can't find a shoreline with integrated float switch (although just saw that you purchased it, so should come with instructions and wiring diagram, no?)

Give a link to the wiring diagram or directions. Does your helm switch just have the pump wire on one side and 12v on the other? Switched or no?

 

[dingbat]