I read an advertorial on BoatUS.com on pump capacity and because Google is smart it serves my an article on a sailing crew fighting to keep up with the incoming amount of water after a collision with a whale or container or refrigerator. Which made me added 2 essential parts on my safety list on preparing our Seawind 1260 for an circumnavigation.
Bilge pump real capacity
Interesting article with one picture saying it all. In a normal situation you will lose ~50-70% of the advertised capacity of a bilge pump. 70% of 2.000 litre per hour ( ~510 gph) is a 10 ltr bucket per minute. Alternatives are water intake of your engine, 70-100 litres per minute and the manual bilge pump at a max of 50 litres per minute.
It will handle a leak on your water system, rain, sea or bow water in heavy conditions. But it is a false feeling of safety to think it will keep you afloat.
Industrial Sewage Pump
Part of the problem is the use of 12 volt DC. You need a lot of ampere to obtain a higher wattage. So switching to 230 volt AC is a first step. Second step is you need a more industrial design to pump a higher volume. So after looking around I opted for a sewage pump of Vevor, heavy duty, big hose etc. You need electricity, at least one engine running and your converter higher up, not in the engine room.
Everybody odd to have conic wooden plugs for an broken valve or hull transit. But for a real crash or a rip that is useless. A lot of stories and experiments on other solutions. Remarkable good is stuffing a pillow into the crash hole securing it with wooden beams etc. In a closed bow compartment stuffing in fenders, classic cork life jackets etc to suppress the water and obtain bouncy, also works. For larger cracks a sail outside the hull, but it is difficult to deploy and to keep it in the right place. And of course there is fiberglass and epoxy.
A Spanish company, aplTec, took that idea to the next level and developed a product called Composite Patch, a easy to deploy fiberglass sticker to repair survives, even underwater. It´s around now for a decade and seems to work quit well. The shelf life is 18 months.