check valve for bilge pump

[Pat]

New boat to me. Bilge pump cycles on and off constantly due to the fact that whatever water is in the hose flows back into the bilge after the pump shuts off. Has anyone installed a check valve to prevent this? What type? What size is the hose? I have seen some in West Marine but not sure which to buy. I assume I would try to install check valve as close to the bilge pump as possible in the bilge? Or should I place it douwn stream a bit out of the water? Thanks mates!

 

[Mick]

Check Valve in Bilge Pump

A check valve can create other problems in pumping out the bilge if placed in the wrong location. A proper automatic setup should not cycle with the normal level that is in the bilge. A check valve just ahead of the pump would keep the water out of the bilge, but the pump may have trouble forceing the valve open with the pressure of the water in the hose on the valve. I would look at the complete system from the pump to the exit to make sure it is workable for the pump being used.

 

[Jack2438]

Pat

If you search the archives you will find much more info on the subject. As Mick pointed out a check valve isn't a good idea because it can foul {plug up} and your pump will not discharge. I would check to see if the bilge discharge thru hull goes underwater while motoring, this could cause a siphon and would have the bilge pump running constantly. If this is the case you would want to install a anti-siphon loop vent. You can find them at West Marine or elsewhere. good luck, Jack

 

[jr mell]

my friend put a check valve in their C30

My friend put a back flow preventer on their bildge pump because when under power with people in the stern the bildge pump cycled on, shut off and didn't cycle on again. The discharge on the C30 was underwater at the time so it created a syphon and filled the entire cabin up with almost 2 feet of water before anyone noticed. I recommend it to anyone, and i put one in mine as well.