Originally Posted by Nicholson58
Many bilge pump makers say no to check valves. The consideration is that they can become blocked. I have only ever found them to simply fail to fully close.
All discharges should go to high points and over a loop with a vacuum (anti-siphon) breaker. The vents are high and as near to centerline as can be reasonably done. This is to locate the siphon breaker so that is always above the waterline. On our boat
various discharge flows are then ducted to cockpit
drains or deck
scuppers. The drain after the high loop and vent is gravity down a large pipe. In this design, a check valve is not needed to keep miscellanies water from the bilge and the bilge line is alone...
Thanks for this, Nich. I had 4 really slow (pocketa-pocketa) heavy Jabsco
bilge pumps, & replaced them with Rule
Centrifugals, but those don't have valves, & the outlet is not very high above the waterline & it's shared by the manual bilge pump. So I put in check-valves, but I've had several problems with them, including them not closing properly.
A loop may well solve my problems, but while centrifugal pumps can pump a LOT of water quickly, they don't like much head
. I think max head
on my Rule
1300s is about 3'/1m. Do you have a solution here? TIA