Mercury – Quicksilver Water Pump Repair Kit | Cooling System Component | 4–4.5HP 2-Stroke Outboards | 70941A3

Overview

A strong water pump keeps your outboard running cool and dependable. The Mercury Marine 70941A3 Quicksilver Water Pump Repair Kit is built for Mercury and Mariner 4–4.5HP single-cylinder 2-stroke outboards, giving you everything you need to restore proper cooling flow. This all-in-one kit includes the impeller, upper and lower housings, gaskets, seals, water tube, drive key, and face plate — making it one of the most complete OEM kits available for older outboards. It’s a simple way to bring your vintage motor back to reliable, factory-level cooling performance.

Key Features

• Purpose: Rebuilds the entire water pump assembly to restore full cooling flow.
• Contents: Includes impeller, housings, drive key, gaskets, seals, water tube, and face plate.
• Material: Built from marine-grade rubber and corrosion-resistant components for long life.
• Performance: Ensures steady water pressure and consistent engine temperature.
• Durability: Handles vibration, heat, and water exposure season after season.
• Ease of Use: Designed for a direct OEM fit — installs easily with standard tools.

Engine & Boat Compatibility

• Mercury 4HP single-cylinder 2-stroke outboards
• Mercury 4.5HP single-cylinder 2-stroke outboards
• Mariner 4HP single-cylinder 2-stroke outboards
• Mariner 4.5HP single-cylinder 2-stroke outboards

Performance & Real-World Benefits

The 70941A3 water pump kit is designed to bring older Mercury and Mariner outboards back to life. With every part you need included, it replaces worn or corroded components that can restrict water flow and cause overheating. The flexible impeller keeps cooling water circulating evenly, while new seals and housings prevent leaks and restore proper pressure.

Once installed, you’ll notice more consistent cooling, smoother operation, and better engine protection — especially during long idle runs or warm summer days.

Why Choose Mercury OEM

The Quicksilver 70941A3 is a genuine Mercury Marine kit, made to fit and perform exactly like the original factory parts. Aftermarket kits may not include all the pieces or use materials that degrade faster in saltwater or high heat.

Mercury’s OEM kits are tested for accuracy, durability, and flow efficiency under real marine conditions. With Mercury parts, you can count on your cooling system to perform properly and keep your engine protected trip after trip.

FAQ

Q1: What engines does this repair kit fit?
It fits Mercury and Mariner 4–4.5HP single-cylinder 2-stroke outboards.

Q2: What’s included in the kit?
Everything you need: impeller, upper and lower housings, drive key, face plate, gaskets, seals, and water tube.

Q3: How often should I rebuild the water pump?
Inspect annually and replace every 2 seasons or 200 hours, or sooner if cooling flow decreases.

Q4: What’s the impeller made from?
A marine-grade rubber compound that stays flexible in hot or cold water.

Q5: Why choose OEM?
Mercury OEM kits provide perfect fit, long-term reliability, and complete parts coverage — something aftermarket kits rarely match.