Second Bilge Pump

I will be keeping my war wagon on a floating dock most of this year. I am going to install a second bilge pump with a float just in case.

The q I have is: Can I just “T” the outlet into my current bilge bump? Or can water back flow through the other bilge pump? and I need to add a second water exit hole in my hull? I just have a cheepy new bilge pump from cabelas in there now.

I would run separate discharges. In the event of an epic failure, you don’t want to chance the possibility of a backflow

Evan Pheneger wrote:

The q I have is: Can I just “T” the outlet into my current bilge bump? Or can water back flow through the other bilge pump?

I’ve never tried it, but I would say it’s not a great idea. Bilge #2 will force water back down the discharge and into Bilge #1. I’m not sure if this would cause any major issue if just Bilge #1 was operated, but …

The other problem comes if you wanted to run both Bilge Pumps together. Discharge hoses are almost never sized big enough for even 1 pump, let alone 2. So you would be severely limiting the pumping capacity of both pumps by tying them together into one outlet at best. At worst, the more powerful pump would back feed into the lesser of the 2 and make that pump totally ineffective.

I think I’d want a seacock on either bilge to prevent backflow OR even better IMO would be twin discharges.

Also, there are a couple of other fatal flaws with most bilge installations:

1. That corregated dischareg hose robs pump efficeincey. It’s crap.

2. Undersized wire is often used, which chokes the pump. Wire must be sized for the full amperage draw of the pump, plus 20%, AND including calculating to compensate for the length of the run. I shake my head every time I see a new walleye boat with a bilge pump that has 16 gauge wire and is 15+ feet of wire run from the power source. That pump is probably operating at 25% of rated capacity or less.

Grouse

Randy Wieland wrote:

I would run separate discharges. In the event of an epic failure, you don’t want to chance the possibility of a backflow

Agree. No one plans for it but when you have a lot of water to get out of your boat you will be running both pumps. The extra discharge will be very welcome if you ever find yourself in that situation.

Good notes guys. I think I will add another exhaust. If I am ever in an emergency situation taking on water I don’t want a failure.

Evan Pheneger wrote:

Can I just “T” the outlet into my current bilge bump? Or can water back flow through the oth

I think you would create a Venturi which would ventilate the outgoing flow of water and greatly reduce your pumps gph.

Me personally. Always have a primary bilge pump with an automatic float.

Also. Water will flow back through your pump. When your pump stops running, the hose drains through your bilge pump.

There was a time I ran a auto/manual. Only reason for that was a quick check with the manual switch and I could confirm an operational pump.

I would think you could use the one discharge IF you install a check valve on the other line to prevent the back pumping. If you really want to be fancy a solenoid valve on the manual line would only open when that pump is on.

Always a decision when drilling more holes in a boat.

Good luck. Let us know how it turns out.