17620-ZZ5-003 Fuel Filler Cap - Overview. The 17620-ZZ5-003 Fuel Filler Cap is a vital component in Honda marine engine systems. Its primary function is to securely seal the fuel tank, preventing fuel spills and contamination while maintaining optimal engine performance. Designed for Honda marine engines, this cap ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. Genuine OEM Honda Fuel Filler Cap designed to meet factory specificatio