Adding a bilge pump

Posted by lance_ryley (lance_ryley@…>)

If it were me, I’d add a dedicated line for the bilge pump. I’d run
the line from the lowest part of the bilge to a vented loop located
near the hull, and I’d put the discharge above the waterline. On
Glory, it’s located on the starboard side in the forward head. On
Bright Star, the bilge pumps went through the transom. I think I
prefer the transom discharge because it’s not underwater on port
tack. However, in either case, a vented loop or at the very least a
check valve to ensure you don’t get water back into the boat when
(not if) the fitting is underwater.

The hole for the thru-hull should have the core reamed out (you can
use a bent nail on a drill) and then filled with epoxy to prevent any
core moisture, then bed the thru-hull fitting itself with 4200 or
5200.

For the pump itself, I prefer to use one that doesn’t have a built in
float switch, then adding a solid-state (no moving parts) switch. It
helps to use a bilge switch with a manual override, but otherwise,
wire a switch in parallel with the float so that you can override it
in an emergency. On Glory, I plan to add at least a light at the helm
to indicate when the pump is running, because the bilge is so far
below the cockpit that with the engine running I’d never know it. A
buzzer might be useful as well. For the hose, don’t use the ‘bilge
hose’ that’s sold at West - it’s very lightweight corrugated hose,
very flexible, but has a tendency to eventually crack longitudinally.
I’d go with a smooth-walled, noncollapsible type hose, preferably
without reinforcing wire in it, since this too will eventually fail.
Double-clamp at the thru-hull and at the pump for extra safety.

Hope this helps.

Lance
Glory