Mercury/Mariner 40–60 HP 4-Stroke Outboard Impeller

This impeller is specifically designed for Mercury/Mariner four-stroke outboards in the 40–60 HP range. These 3-cylinder engines – including the popular BigFoot (Command Thrust) models – rely on a robust impeller to pump cooling water through the motor. Our replacement impeller matches Mercury’s specifications (part #47-19453T) to ensure your outboard stays within safe temperature limits at idle and at full throttle.

Whether you’re trolling at low speeds or cruising at high RPM, this 6-blade impeller maintains steady water circulation to protect your engine from overheating. Its neoprene rubber vanes are durable yet flexible, creating a tight seal within the pump housing for efficient operation. This impeller is a must-have spare for owners of 40–60 HP Mercury 4-strokes, allowing quick maintenance and peace of mind on fishing trips and family outings.

• Engine Applications: Ideal for Mercury/Mariner 40, 50, 60 HP 4-stroke outboards (both carbureted and EFI versions, ~1998 onward). Includes compatibility with 50HP BigFoot and 60HP FormulaRace or Command Thrust variants that use the same pump.
• Boat Use: Perfect for small boats (4–5 m) such as aluminum fishing boats, inflatables/RIBs, and tenders powered by these engines. Maintains proper cooling during prolonged idling (trolling) as well as quick accelerations.
• Restore Performance: Replacing a worn impeller with this OEM-equivalent unit restores factory cooling performance, preventing overheating on hot days or when running the engine hard. A cool engine runs more efficiently and lasts longer.
• Installation: Designed for easy DIY installation with basic tools. The precise molding ensures it slides into the water pump housing correctly and forms a reliable seal, saving you time during impeller changes.
• Be Prepared: It’s wise to carry a spare impeller on board, especially for remote fishing spots or extended trips. If you notice a weak cooling stream (tell-tale), it’s time to replace the impeller to avoid engine damage.