Bilge Pump Polarity?


Regular Contributor
Just replaced the bilge pump in my 1995 Ski Sanger Tournament Tow Boat. As far as I know, it's a simple 12v negative ground electrical system. The pump was operational last season, but didn't run when I turned it on yesterday. Ordered the parts and Amazon delivered them today. I replaced to old pump with an identical model, a Sea Sense 800 GPH Fully Automatic BP. The old pump had frozen and was inoperable. I also replaced the 5A pushbutton circuit breaker and the ON/OFF SPST switch. The old one fell to pieces when I removed it from the instrument panel. No signs of any burning in the switch. The breaker tested bad for continuity. Hooked everything up and flooded the bilge while to boat was on the hoist. The pump turned on, but nothing came out the pump port on the starboard bow. By then, the sun was going down, so I quit for the day. Tmrw, I'll disconnect the hose and see if it's blocked. Is there any way I could have re-attached the wiring to the breaker and the switch so the pump runs backward? Many thanks for your help, PW
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I don't think you can have a polarity reversal with the wiring at the switch or the breaker...

I'd pull the hose at the pump and then retry the switch...most all pumps expel enough product that its easy to tell if the pump is functional...if that's good, then its time to check the hose/thru hull...
Try to test the bilge pump and switch in a plastic kitchen basin first. You need spare battery. The real reason for this is it allows my body to get into a bilge pump replacement position only once.
The outlet hose was blocked. Not really sure how that could happen. Ran a 3/8" x 20' hand-crank plumbing snake thru it and problem solved. Thanks for the tips! PW