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A valve in the hull of a boat or ship that may be opened to let in or discharge water, as in filling or emptying a ballast tank.


(Nautical Terms) nautical a valve in the hull of a vessel below the water line for admitting sea water or for pumping out bilge water



a valve in the hull of a ship for admitting seawater into some internal chamber, as for ballast.
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Open and remove seacock assemblies for Coast Guard inspection, clean same and reinstall as required.
Billy O'Connor of the Hook Sub-Aqua Club said there was a possibility that the boat's seacock - a water valve - may have malfunctioned and failed to discharge the water it was taking in to cool the engine.
A small leak might short out the high water alarm, so you only discover that the bilge pump is blocked when your feet get wet; or you find a split hose and then you find out that the seacock connected to it is seized open?
Dealing with a leaking seacock, inoperative pump or no power to a main distribution panel, once you've left the safety of the harbor, can be far beyond an inconvenience.
Having two pumps already plumbed, so that if one fails, you can flip a seacock and switch to another one.
A through-hull, seacock and strainer are needed for the seawater supply and an above-waterline through-hull needed for the seawater discharge.
Standard features include twin 28-gallon livewells under the aft casting deck along with a 12-gallon crustacean well forward (all are blue gel-coated with LED lighting), ten gunnel mounted rod holders (two of which are Mate Series Cup/Rod holders), twin removable 72-quart performance coolers, all forged stainless steel through-hull fittings with Marelon seacocks (composite/non-corrosive), 6-inch jack plate; custom powder-coated leaning post with backrest, rigging tray, four rod holders, SS cup holders and tackle storage; Wet Sounds audio, 12-inch multi-function electronics, custom upholstery with contoured seating and cushions with coaming bolsters (cockpit and bow), two forward tackle storage centers and more.
Each crew member should know the locations of seacocks, fire extinguishers, the emergency tiller, the medical kit, and how to operate the jury-rigged rudder (legendary for not working, so practise steering with the sails, the only proven reliable method).
All his ships hoisted the German flag, the seacocks, portholes, watertight doors, hatches and torpedo tubes were opened and the crews now totalling fewer than 2,000 men took to their lifeboats as the ships began to sink with tremendous hissings of steam, spouts of water and huge sucking and gurgling sounds.
I have been around so many people, from so many places, standing in bars over the long hours that are the open seacocks that scuttle many lives, hearing so many tales and recounted conversations.
We had some hilarious moments, but eventually we learned to just scuttle the ships by making holes above the waterline, then knocking the seacocks off in the bilge.