17621-ZV0-020 Fuel Cap Body - Overview. The 17621-ZV0-020 Fuel Cap Body is an essential component within Honda marine engine systems. As part of the fuel tank sealing assembly, it plays a critical role in securing the fuel reservoir, preventing fuel leaks, and maintaining system reliability under marine conditions. Designed specifically for Honda engines, it ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. This part functions as the