WATER PUMP BODY 46-42089A2

Function and technical context

The water pump body is the central component of the cooling system of small displacement Mercury engines. This piece houses the impeller and channels the flow of water from the inlet to the cooling chambers of the engine block, ensuring constant circulation that dissipates the heat generated during combustion. Its correct operation is critical to avoid overheating of the engine, which can cause irreversible damage to gaskets, cylinders and cylinder head. Wear or breakage of the body compromises the tightness of the circuit and can allow water to enter areas where it should not circulate, generating internal corrosion and loss of performance.

When to replace this part?

The pump body should be inspected regularly during seasonal maintenance, especially if the motor has been operated in turbid or silty water. Symptoms of failure include abnormal engine overheating, visible loss of coolant from the water circuit, irregular noises in the pump or visible cracks in the housing. It is recommended to check the condition of the body every 100-150 hours of operation and replace it preventively if signs of erosion, corrosion or deformation are detected. Early replacement prevents costly breakdowns and ensures that the cooling system remains effective throughout the boating season.

Mercury and MerCruiser Engine Compatibility

Compatible Mercury Mariner Engines

Equivalent manufacturer part numbers