Answer
Apr 18, 2023 - 05:19 PM
This answer is primarily centered around the block used by Mercruiser Volvo Crusader and some others.
There are two water pumps on a marine system.
One pump circulates the glycol or antifreeze or fresh water through the engine block’s water jacket and possibly the manifolds depending on what closed cooling system is being used.
The other water pump is for moving the seawater through the raw water circuits in either the heat exchanger and exhaust above the manifold. Or, it’s the pump for circulating raw water throughout the engine jacket and exhaust. Again it depends on the closed cooling system type you’re using.
Please see definitions for raw water and fresh water in relation to a marine cooling system.
In a marine cooling system, the circulating pump (what we call a water pump on a car) is responsible for circulating the coolant (fresh water or antifreeze) through the engine to absorb heat, and then through a heat exchanger where it is cooled by seawater before returning to the engine.
The water pump is typically driven by a belt connected to the engine's crankshaft, and its impeller is housed in a housing known as a "pump body." As the impeller rotates, it creates suction that draws coolant into the pump body through an inlet port. The impeller blades then force the coolant through the pump body and out through a discharge port, where it is directed into the engine's cooling passages.
One important consideration in marine cooling system design is the need to prevent seawater from entering the engine itself. This is typically accomplished through the use of a heat exchanger, which separates the engine's coolant from the seawater used to cool it. In a typical heat exchanger design, seawater is pumped through a separate set of tubes or passages that run parallel to the engine's cooling passages, allowing heat to transfer from the engine coolant to the seawater without the two fluids mixing.
©2023 Mr. Cool Marine LLC
There are two water pumps on a marine system.
One pump circulates the glycol or antifreeze or fresh water through the engine block’s water jacket and possibly the manifolds depending on what closed cooling system is being used.
The other water pump is for moving the seawater through the raw water circuits in either the heat exchanger and exhaust above the manifold. Or, it’s the pump for circulating raw water throughout the engine jacket and exhaust. Again it depends on the closed cooling system type you’re using.
Please see definitions for raw water and fresh water in relation to a marine cooling system.
In a marine cooling system, the circulating pump (what we call a water pump on a car) is responsible for circulating the coolant (fresh water or antifreeze) through the engine to absorb heat, and then through a heat exchanger where it is cooled by seawater before returning to the engine.
The water pump is typically driven by a belt connected to the engine's crankshaft, and its impeller is housed in a housing known as a "pump body." As the impeller rotates, it creates suction that draws coolant into the pump body through an inlet port. The impeller blades then force the coolant through the pump body and out through a discharge port, where it is directed into the engine's cooling passages.
One important consideration in marine cooling system design is the need to prevent seawater from entering the engine itself. This is typically accomplished through the use of a heat exchanger, which separates the engine's coolant from the seawater used to cool it. In a typical heat exchanger design, seawater is pumped through a separate set of tubes or passages that run parallel to the engine's cooling passages, allowing heat to transfer from the engine coolant to the seawater without the two fluids mixing.
©2023 Mr. Cool Marine LLC
