90506-ZY3-000 Washer - Overview. The 90506-ZY3-000 Washer is a genuine Honda marine engine component designed to function as a propeller thrust washer within Honda marine engine systems. This washer plays a critical role in the assembly of marine lower units, particularly in propeller shaft assemblies, where it facilitates smooth and reliable operation by properly positioning and securing the propeller and related components. By maintaining correct alignment and providing adequate thrust distrib