UANOFCN Outboard Water Pump Impeller Kit Model: 6H3-W0078-A0, 50-70 HP complete rebuild kit with housing and seals

The UANOFCN 6H3-W0078 Outboard Water Pump Impeller Kit is a complete replacement assembly designed to restore cooling performance on Yamaha 50–70 HP outboards by replacing the impeller, housing, seals, and related hardware.

When a marine engine’s cooling system begins to fail, replacing the water pump impeller and associated components is a priority to prevent overheating and maintain reliable operation. This kit is tailored to fit many Yamaha 50–70 horsepower outboard models and contains the parts needed for a thorough pump rebuild, saving you time hunting down individual pieces.

Which Yamaha engines and part numbers does this kit fit?

This kit covers a wide range of Yamaha 50HP, 60HP, and 70HP outboard models including T50, FT50 series, T60, FT60 series, 60F, P60, E60, C60, and 70B/C70 variations. It is offered as a direct replacement for OEM part numbers and common aftermarket cross-references.

• Compatible Yamaha models: T50, FT50B/C/G/J, T60, FT60B/D/G, 60F, P60, E60, C60, 70B, C70
• OEM equivalents: 6H3-W0078-00-00, 6H3-W0078-A0-00, 6H3-W0078-02-00
• Additional cross-references: 6H3-44311-00-00, Sierra 18-3461, 18-3466

What parts are included and why they matter?

The kit contains the impeller and its mating components so you can rebuild the pump assembly without needing extra parts. Including both gaskets and the housing means you replace wear-prone items that commonly fail together, improving long-term reliability.

• Impeller and impeller key — restores water flow and timing
• Wear plate, outer plate gasket, and o-ring — ensure proper sealing and surface contact
• Water pump housing plus insert cup — replaces corroded or damaged housing elements
• Bolts and water pump gasket — hardware to secure and seal the assembly

How does installing this kit affect engine maintenance and performance?

Replacing the impeller kit prevents cavitation and poor coolant circulation that can lead to overheating and reduced engine lifespan. A full rebuild with matching seals and housing returns the pump to near-original condition and reduces the chance of repeat service shortly after repair.

• Restores reliable cooling capacity for consistent RPM under load
• Eliminates leaks and improves seal integrity with included gaskets and o-rings
• Reduces service frequency since worn housing elements are also replaced

What should you consider before buying and during installation?

Confirm model year and part numbers on your engine to ensure compatibility, and inspect the driveshaft and impeller cavity for damage before installation. Follow the engine manufacturer’s torque and assembly guidelines; use marine-safe lubricants on rubber parts during fitment to avoid damage.

• Verify engine model and OEM part numbers match kit cross-references
• Inspect pump cavity, shaft, and cooling passages for corrosion or debris
• Use recommended torque specs and marine-grade grease during assembly

Who is this for: Boaters, marine technicians, and do-it-yourselfers who own Yamaha 50–70 HP outboards and need a comprehensive water pump rebuild kit. It’s especially useful for those restoring older engines, performing preventive maintenance before a boating season, or replacing a failed impeller and worn housing in one service session.