91318-V15-003 O-Ring - Overview. The 91318-V15-003 O-Ring is a vital sealing component used in Honda marine engine systems. This high-quality O-Ring ensures a watertight or airtight seal at critical connection points within the fuel or water systems, preventing leaks and maintaining optimal engine performance. Designed specifically for Honda, it ensures seamless integration with existing parts, maintaining optimal performance and durability.. Key Features. The 91318-V15-003 is a genuine OEM Hond