Mercury MerCruiser / Quicksilver Water Pump Repair Kit – 42089A5

Restore proper cooling performance with the genuine Mercury Marine / Quicksilver 42089A5 Water Pump Repair Kit. This OEM service kit includes the essential components required to rebuild the lower-unit water pump, ensuring reliable raw-water flow through the engine’s cooling system to prevent overheating and maintain optimal engine performance.

Manufactured to Mercury Marine’s original equipment specifications, this kit provides a direct replacement solution for worn water pump components in compatible Mercury and Mariner outboard engines.

Key Features

• Genuine Mercury / Quicksilver OEM water pump repair kit

• Restores cooling water circulation through the outboard engine

• Helps prevent engine overheating and cooling system failure

• Includes critical pump service components for a complete repair

• Designed for reliable performance in harsh marine environments

Kit Includes

Typical kit components include:

• Water pump impeller

• Pump housing

• Wear plate

• Gaskets and O-rings

• Key and installation hardware

(Exact contents may vary slightly depending on production revision.)

Replaces / Cross Reference

• Mercury 46-42089A5

• Sierra 18-3320 aftermarket equivalent

Compatible Mercury / Mariner Engines

Commonly used on Mercury and Mariner outboard engines, including:

• 75 HP outboards

• 80 HP outboards

• 90 HP outboards

• 100 HP outboards

• 115 HP outboards

• 125 HP outboards

Typically used on inline 4-cylinder 2-stroke Mercury / Mariner outboards, depending on serial number range.

Service Recommendation

Water pump components are wear items and should typically be inspected annually and serviced every 100 hours or once per season to maintain reliable engine cooling.

Important Compatibility Note

Water pump kits may vary by engine model, gearcase type, and serial number range. Always verify compatibility using the engine serial number before ordering to ensure the correct repair kit.