WATER PUMP BODY 663-44311-00 REC663-44311-02

Function and technical context

The water pump body forms the central structural component of the cooling system in Yamaha outboard engines. This piece houses the impeller and channels the flow of seawater through the cooling circuit, allowing continuous dissipation of the heat generated during combustion. Its structural integrity is essential to maintain the circulation of refrigerant under pressure and avoid leaks that compromise the thermal efficiency of the system. A deteriorated, cracked or advanced corroded body causes a loss of pressure in the cooling line, which leads to progressive overheating of the engine and, in critical cases, permanent damage to the cylinders and internal components.

When to replace this part?

Replacement of the pump body is required when water leaks are detected around the union with the impeller, severe corrosion on the surface or visible cracks in the housing. Although there is no predefined fixed maintenance interval, it is advisable to inspect this part during the annual seasonal inspection, especially on boats that operate in salt water or in conditions of high use and thermal demand. Preventatively replacing the body when replacing the impeller ensures optimal sealing and avoids costly boating repairs.

Compatible Yamaha engines

Equivalent manufacturer part numbers