Mercury – Quicksilver Replacement Water Pump Kit | 9-Piece Cooling System Service Set | 803750A03

Overview

Keep your outboard running cool and dependable with the Mercury Marine 803750A03 Quicksilver Replacement Water Pump Kit. This 9-piece OEM-quality kit provides all the components you need to restore proper cooling flow, including the water pump housing, impeller, plate, and water guide tube. Designed for 2005 and newer Mercury and Mariner 8–9.9HP 4-Stroke outboards, it ensures your engine’s cooling system performs like new, preventing overheating and maintaining peak efficiency throughout the boating season.

Key Features

• Purpose: Rebuilds your outboard’s water pump to restore full cooling performance.
• Complete Kit: Includes housing, impeller, plate, gaskets, and water guide tube for a full-service repair.
• Performance: Delivers consistent water flow for optimal engine temperature control.
• Durability: Features flexible impeller elastomers that handle wide temperature swings.
• Ease of Use: All-in-one OEM kit designed for direct fit and easy installation with standard tools.

Engine & Boat Compatibility

• Mercury and Mariner 8HP and 9.9HP 4-Stroke outboards
• Model year 2005 and newer

Performance & Real-World Benefits

The 803750A03 water pump kit keeps your cooling system at peak efficiency by replacing every critical part in one go. Old or damaged components can reduce water flow and cause overheating, which can lead to expensive repairs. This kit restores full circulation, ensuring your engine runs cool and reliable no matter how hard you push it.

The impeller’s advanced elastomer material offers better flexibility and longevity, maintaining high performance through a range of temperatures. With everything you need in one box, it’s the simplest and most complete way to protect your outboard.

Why Choose Mercury OEM

The Quicksilver 803750A03 is a genuine Mercury Marine part, designed and tested to meet the same standards as the components originally installed in your engine. Aftermarket kits may not fit perfectly or could use lower-quality materials that fail under marine conditions.

Mercury’s OEM design guarantees precise tolerances, high-quality rubber, and corrosion-resistant hardware — delivering the durability and reliability that boaters trust.

FAQ

Q1: What engines is this kit designed for?
It fits Mercury and Mariner 8–9.9HP 4-Stroke outboards from 2005 and newer.

Q2: What’s included in the kit?
A 9-piece set featuring the water pump housing, impeller, plate, gaskets, and water guide tube.

Q3: Why should I replace the entire kit?
Replacing all components ensures consistent water flow and protects against leaks or impeller failure.

Q4: How long does it last?
Mercury recommends inspecting or replacing your pump annually or every 100 hours, depending on use.

Q5: Why OEM instead of aftermarket?
OEM parts guarantee accurate fitment, high-quality materials, and proven performance for lasting reliability.