Bilge pump discharge location

[Plumper II]

The bilge pump has an integral one way valve to prevent back filling.

You have a greater level of faith than I do.

 

[jepomer]

The idea should work for 99% of the time.

BUT, the problem is the remaining 1%. Shortcuts and/or apparent simplistic solutions often fall into this remaining percentage. It doesn't matter if it is a boat or something else.

 

[jimford2158]

My boat has a manual pump mounted in the floor of the cockpit walk-thru and I have run 1.5 inch hose with a checkvalve low in the bilge to prevent drainback. The outlet is just below the gunwhale and is dedicated to the pump system. I have also tested it by dumping water into the bilge and operating it and it pumped out very quickly. I also have 2 electric pumps and the batteries are mounted 2 and 3 feet above the sole, bank 1 and bank 2, to prevent shorting any sooner than they have to.