Most modern yachts have electric bilge pumps. Whilst they are a great convenience they do have limitations.
They are usually fairly low volume and most are not able to remove enough water fast enough to keep a holed vessel afloat.
They can burn out easily if left running when there is no water to pump.
But the main limitation of them is that, on boats where they have been fitted they become the only means that is ever used to remove water form the bilge.
As a result there is no certainty that the manual pumps will work when required.
If you have several pumps on board, it is good practice to use all of them regularly and to rotate the pump that is used to remove any excess bilge water.
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