19210-ZW1-303 Pump Impeller - Overview. The 19210-ZW1-303 Pump Impeller is a critical component of the Honda marine engine cooling system. It operates within the water pump to draw and circulate water, preventing the engine from overheating and ensuring consistent performance. Designed specifically for Honda outboard motors in the 75-90 HP range, it is essential for maintaining the longevity and reliability of your marine engine. Crafted to exact factory specifications, this impeller ensures sea