90402-ZV5-821 Seal Washer - Overview. The 90402-ZV5-821 Seal Washer is a crucial component within Honda marine engine systems. It serves the purpose of sealing specific joints or parts to prevent fluid leaks and contamination, ensuring the smooth and reliable operation of the marine engine. This seal washer is specially engineered to fit precisely into Honda marine engine assemblies, providing optimal sealing performance and durability.. Key Features. Genuine OEM Honda Seal Washer designed for m