WATER PUMP BASE 46-8M0077147

Function and technical context

The water pump base is the structural assembly that houses the impeller and internal components of the cooling system of Mercury marine engines. This piece acts as the central body of the fresh and salt water circulation circuit, guaranteeing the constant flow of coolant towards the engine galleries and heat exchangers. A failure or deterioration in this base compromises the tightness of the system, causing cooling water leaks, overheating of the engine block and, in extreme cases, entry of seawater into protected areas of the engine, which generates internal corrosion and catastrophic failure.

When to replace this part?

Signs of degradation in the pump base include visible limescale deposits, cracks in the housing, water leaks in the joint area and progressive loss of efficiency in engine cooling indicated by abnormal temperature rise. It is recommended to check this part at each seasonal maintenance service, especially after sailing in waters with high saline or sediment content. Preventative replacement of the base when any signs of corrosion or wear are detected avoids costly emergency repairs and ensures the reliability of the cooling system in high-altitude navigation.

Compatible Mercury Mariner Engines

Equivalent manufacturer part numbers