PUMP KIT 65N-W0078-A1

Function and technical context

This pump kit constitutes an essential component of the cooling system in Yamaha outboard engines, responsible for the forced circulation of the coolant through the internal passages of the engine. The pump maintains a constant flow that dissipates the heat generated in combustion, preventing overheating of the cylinder liners and cooling galleries. Poor operation of this kit compromises the cooling capacity of the propellant, potentially causing irreversible damage to the cylinder head, gaskets and internal seals.

When to replace this part?

Common symptoms of cooling pump failure include an abnormal increase in engine temperature indicated on the control panel, loss of discharge water flow from the side of the casing, or abnormal noises coming from the impeller area. It is recommended to inspect the kit and its components every boating season or after 100-150 hours of operation, especially in waters with sediment or high salinity. Preventive replacement avoids critical situations of overheating during navigation that can leave the boat immobile in the water.

Equivalent manufacturer part numbers