YAMAHA WASHER 90201-23M01 REC90201-23M01

Function and technical context

This washer is part of the fixing and sealing systems in Yamaha engines, fulfilling a critical function in retaining components subjected to constant vibrations and intense thermal cycles. Its mission is to evenly distribute the tightening load in the joint areas, preventing specific stresses from damaging aluminum or steel surfaces. In the context of marine propulsion, any play or detachment in these joints can cause leaks of tightness, water entry into crankcases or cooling systems, and accelerated wear in bearings and seals. The correct installation and condition of this part is essential to maintain the structural integrity of the engine block under the demanding operating conditions in salt and fresh water.

When to replace this part?

Washers require replacement when they present permanent deformations, advanced corrosion, cracks or when weakening in the tightness of the associated bolts is detected during maintenance checks. Although they do not have a specific hourly interval like impellers or filters, it is advisable to inspect their condition with each disassembly of critical components (cylinder head, crankcase, water pumps) and replace them preventively if they show signs of rust or fatigue. Replacing these worn parts preventively avoids costly emergency repairs, especially in deep-sea navigation where a leak can compromise the viability of the voyage.

Equivalent manufacturer part numbers