YAMAHA 90209-24M03 LOCKING WASHER REC90209-24M03

Function and technical context

This sealing washer is part of the sealing system of the Yamaha engine, acting as a sealing element at critical points where components subjected to pressure and movement come together. Its mission is to guarantee the tightness of the joints, preventing leaks of salt water, coolant or oil into areas of the engine that should not be reached by these fluids. The correct operation of this washer is essential to maintain the internal structural integrity of the propeller, since any leak compromises the lubrication, cooling and useful life of adjacent components.

When to replace this part?

Lock washers degrade due to continuous thermal cycling, marine corrosion and progressive crushing after multiple tightening and loosening. Symptoms of deterioration include dripping around the sealing area, moisture in adjacent cavities, or gradual loss of cooling system pressure. It is recommended to check the condition of these washers during each seasonal maintenance, especially in engines with more than 300-400 hours of operation, and replace them preventively during disassembly of critical components. Changing this part proactively prevents unexpected breakdowns while sailing and prolongs the overall reliability of the engine.

Equivalent manufacturer part numbers