90509-ZY9-000 Washer (13mm) - Overview. The 90509-ZY9-000 Washer (13mm) is a vital hardware component designed to support Honda marine engine systems. This flat washer plays a crucial role in distributing load evenly during fastening, preventing damage to parts, and contributing to the overall reliability and durability of your marine equipment. Engineered to meet exact OEM specifications, this washer ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. Genuine Honda OEM part designed specifically for marine engine applications.. Flat, plain metric washer measuring 13mm in diameter.. Helps distribute load and prevent damage to fasteners and mating surfaces.. Manufactured to meet exact factory specifications and tolerances.. Ensures precise fit and compatibility with Honda marine hardware.. Designed for longevity and performance in harsh marine environments.. Why Choose Genuine OEM. Using original Honda parts like the 90509-ZY9