Mercury – Water Pump Assembly | Alpha Sterndrive Cooling System | OEM Composite & Metal | 8M0113733

Overview

There’s a certain comfort that comes from knowing your engine’s cooling system is doing its job. When you ease the throttle forward and feel the boat lift, that quiet confidence is built on the small parts you rarely see — like the water pump keeping everything cool and steady beneath the deck. The Mercury 8M0113733 Water Pump Assembly delivers that kind of trust. It’s the part that lets you enjoy the ride instead of worrying about engine temperature or unexpected shutdowns, no matter how long the day on the water runs.

Key Features

• Complete water pump assembly designed for dependable cooling performance
• Fits MerCruiser 3.0L TKS Alpha Plus engines (Serial No. 1G700000–1G799999)
• Includes all necessary components for a clean, proper replacement
• Built from OEM-approved metals and composite materials for long-term reliability
• Engineered to meet Mercury Marine’s original equipment specifications

Engine & Boat Compatibility

• Compatible with MerCruiser 3.0L TKS Alpha sterndrive engines
• Also suitable for select MerCruiser 3.0L MPI EC Alpha configurations
• Common on runabouts, bowriders, small cruisers, deck boats, and entry-level sport boats
• Ideal for engines that run in warm climates, carry heavy loads, or spend long days at low speeds where cooling matters most

Performance & Practical Benefits

A healthy water pump affects everything about the way an engine performs. With a new Mercury 8M0113733 assembly installed, cooling flow becomes smooth and consistent, allowing your engine to settle into a stable idle and maintain safe temperatures under load. The difference shows up in the way the engine reacts — quicker to respond, less prone to heat fade, and steady even when pushing through choppy water or towing.

Because this is a full assembly, all components fit together cleanly and securely. The pump housing aligns without fuss, the impeller seats properly, and the gaskets create a tight, trustworthy seal. On the water, that translates into a cooling system that feels “locked in” — tight, quiet, and reliable. The materials stand up well to corrosion, heat cycles, and long-term exposure, giving boat owners more seasons before the next replacement. It’s a simple upgrade that keeps you on the water longer and protects your engine from costly overheating damage.

Why Buy OEM

With cooling components, precision matters. Aftermarket assemblies may look similar, but even small variations in housing shape or impeller quality can create performance issues. Mercury Marine part number 8M0113733 is engineered specifically for the 3.0L TKS and MPI EC Alpha engines, delivering proper flow rates, correct tolerances, and proven durability.

Choosing OEM ensures you get a part that fits right the first time, installs cleanly, and performs exactly as your engine was designed to run. It’s a practical, cost-effective decision that protects both your powerplant and your time on the water.

FAQ

Q1: Which engines does the Mercury 8M0113733 Water Pump Assembly fit?

It fits MerCruiser 3.0L TKS Alpha engines with serial numbers between 1G700000 and 1G799999.

Q2: What makes this assembly better than aftermarket alternatives?

OEM engineering ensures correct tolerances, proper cooling flow, and long-term reliability in marine environments.

Q3: How can I confirm this is the correct part?

Match your serial number range or check your owner’s or service manual for Mercury Marine part number 8M0113733.

Q4: Is it suitable for both freshwater and saltwater use?

Yes — the materials are designed for durability in all marine conditions.

Q5: Is installation straightforward?

Most boat owners with basic mechanical experience can install it using common shop tools.