91254-ZW1-003 Water (Lower) Seal - Overview. The 91254-ZW1-003 Water (Lower) Seal is a crucial component of the Honda marine engine systems. It supports the lower unit system by preventing water from entering critical internal components, thereby maintaining the integrity of the engine's lubrication system and ensuring long-term reliability. Engineered to Honda's exact OEM specifications, this seal ensures seamless integration with existing parts, maintaining optimal performance and durability..