WASHER 90201-16M00 REC90201-16M00

Function and technical context

The 90201-16M00 washer is a critical fastening component in Yamaha and Mercury marine engine fastening and sealing systems. This piece works together with bolts and nuts to distribute the tightening load evenly, preventing pressure from concentrating in specific areas of the base metal. Its correct installation is essential to maintain the structural integrity of joints subjected to continuous vibrations, temperature changes and mechanical stresses inherent to the operation of nautical thrusters. A failure in this washer can lead to loosening of critical joints, water entering crankcases or lubrication systems, and progressive loss of tightness in sensitive areas of the engine.

When to replace this part?

Washers deteriorate due to plastic deformation after multiple tightening-loosening cycles, corrosion due to exposure to salt water, and loss of sealing capacity. During each maintenance intervention that involves the disassembly of engine components (gasket changes, cooling cleaning, replacement of fixing nuts), it is advisable to check the condition of the washers and replace them if they show deformations, active rust or visible wear. Preventive replacement of washers in larger clearances avoids future watertight problems and reduces the risk of costly repairs in adverse navigation conditions.

Equivalent manufacturer part numbers