Bilge pump dilemma in Cats?

[Wanderlust]

Originally Posted by monte

Lagoon fit non return valves, but in practice they still let the water flow back.

Yes the non return valves on mine are both a bit troublesome. One leaks and the other is stuck almost closed, thus making the bilge pump rather ineffective on that side. That will be one of the first tasks when I get back to the boat.

While I don't normally like non return valves, as these bilge pumps are only the small non critical ones I am OK to live with them .... when they work.

[ProjectManaia]

Thank you all for the many answers, I guess I have mine:
Limber holes for the forward part, leave the front hatch out (which is watertight sealed) install the float switch with the sucking end of the hose in the lowest part, attached to a diaphragm pump, pumping out (obvious) ideally with an alarm on it or a counter, another pump for the engine room compartment, which is watertight and seperate - same setup on the second hull..
Thanks again! Hope it all works out...

[monte]

Well the front sealed hatch could still benefit from a hose and valve to open or close, left open. It would drain any water ingress from leaks or small damage and can be closed if the damage is more than the bilge pump can handle.

[blubaju]

Wonder if most people writing here ever sailed a Catamaran, my recent Schionning design has no bilge at all, between floorbord and hull is bouancy and it is sealed, my last catamaran had a bilge, but in 12 years I have never seen a drop water there. Can anyone tell me why there should be any water in a modern design, engine with saildrive or dry seals? (had both, prefere dryseals)

Sure, accidents do happen, so the enginre compartments have automatic bilge pumps and there is one additional portable in each hull, hose and electric wire long enough to bring it to the compartment needed and drain out of the window, on their storage place they do work as an automatic bilge pump. Yes, doors are 15cm above floor and there is a REED-float-switch with an alarm in every compartment, NO connecting holes as generally there has no water to be there.

[tomfl]

Originally Posted by blubaju

Wonder if most people writing here ever sailed a Catamaran, my recent Schionning design has no bilge at all, between floorbord and hull is bouancy and it is sealed, my last catamaran had a bilge, but in 12 years I have never seen a drop water there. Can anyone tell me why there should be any water in a modern design, engine with saildrive or dry seals? (had both, prefere dryseals)

Sure, accidents do happen, so the enginre compartments have automatic bilge pumps and there is one additional portable in each hull, hose and electric wire long enough to bring it to the compartment needed and drain out of the window, on their storage place they do work as an automatic bilge pump. Yes, doors are 15cm above floor and there is a REED-float-switch with an alarm in every compartment, NO connecting holes as generally there has no water to be there.

I have two outboards in wells on my Seawind and while I have only owned it three years I have never seen a drop of water in my bilge. Do have electric and manual bilge pumps but wonder about how often I should test them to see if they work.