Ships, Boats, Yachts etc?

Question

Why do boats have a hole to the side that emits water when the engines are on?

Answer 1

It the cooling water for the engines. Instead of a radiator they just pump water from the ocean/lake through the engine and back out the side.

Also some bilge pumps may pump water fairly regular as the stuffing box can leak water to cool the propeller shafts.

Answer 2

here are a number of things that can pump water out the side of a boat. Very seldom due the motors pump water out the side of the boat in a stream they either pump the water out the outdrive or through the exhaust. Two other things can pump a continuous stream and that is the bilge pump which should stop, if it does not the boat has a continuous leak. Another thing is air conditioning. The compressor unit in a boat is cooled by sucking water from the outside and pumping water through the a/c unit. As long as the a/c unit is on it will have water pumped through the unit and out the side of the boat.