Honda Water Pump Impeller - 19210-ZW9-A32. Restore strong, consistent cooling water flow with the genuine Honda water pump impeller, part number 19210-ZW9-A32. The impeller is a key wear item inside the water pump, responsible for moving cooling water through the engine. Replacing it on schedule helps maintain proper operating temperature and reduces overheating risk in both saltwater and freshwater use.. Key Features. Genuine Honda water pump impeller for cooling system service. Helps maintain proper cooling water flow and stable operating temperatures. Ideal for preventative maintenance and seasonal service intervals. Supports long-term reliability in harsh marine environments. OEM fit and function for compatible Honda outboards. Fitment. Honda BFP8. Honda BFP9.9. Honda BFP15. Honda BF15. Honda BFP20. Honda BF20. Why It Matters. Impellers wear over time from heat, sand, silt, and normal use. A worn impeller can reduce water flow, leading to weak telltale output and overheating risk.