Yamaha - Outer Plate Cartridge Water Pump System 6E0-44323-00-00. Overview. When you're servicing a Yamaha water pump, the outer plate is one of those parts that can quietly affect how well everything works. It gives the impeller a proper surface to spin against, and once it gets worn or grooved, water flow starts to drop off. I've pulled pumps apart that looked fine until you saw the plate was chewed up from debris. Replacing it helps keep the cooling system running strong and consistent.. Key Features. Smooth Impeller Surface - Provides a clean contact area for proper impeller operation.. Wear-Resistant Construction - Built to handle friction, heat, and debris inside the pump housing.. Supports Cooling Efficiency - Helps maintain consistent water flow through the engine.. OEM Precision Fit - Matches original specifications for correct alignment and easy installation.. Engine & Boat Compatibility. Designed for Yamaha 2-stroke outboard engines using standard water pump assemblies. Comm