Mercury – Anode | Corrosion Protection | Aluminum | 8M0137344

Overview

Every boater knows the quiet comfort that comes from heading out with a motor you trust—one that starts clean, runs steady, and keeps you moving without hesitation. A small but essential part of that reliability is knowing your engine is protected from corrosion, especially if you spend time in water that’s less than gentle on aluminum components. The Mercury 8M0137344 Anode is one of those behind-the-scenes parts that gives you that peace of mind. It works silently, day after day, letting you focus on the breeze, the cast, or the long ride back to the dock instead of what’s happening under the surface.

Key Features

• Protects key engine components from galvanic corrosion
• Marine-grade aluminum formulation for long-lasting performance
• Designed to match Mercury specifications for durability and fit
• Ideal for Mercury EFI outboards in the 9.9–20 horsepower range
• Simple replacement with common hand tools
• Built to maintain structural integrity in both fresh and saltwater

Engine & Boat Compatibility

• Fits Mercury 9.9 horsepower EFI FourStroke outboards (2017 and newer)
• Fits Mercury 20 horsepower EFI FourStroke outboards (2017 and newer)
• Works with engines carrying serial number 0R833820 and above
• Common on tenders, jon boats, aluminum fishing boats, small pontoons, and runabouts
• Effective for boats frequently running in brackish, salt, or highly mineral-rich freshwater

Performance & Practical Benefits

There’s nothing glamorous about an anode, but its job is one of the most important on your motor. Once installed, the Mercury 8M0137344 acts as the sacrificial component—the first line of defense when corrosion tries to take hold. That means the parts that truly matter, like your gearcase and mounting hardware, stay protected.

In real-world use, you’ll notice the difference not because the anode calls attention to itself, but because your engine keeps looking and performing like it should. No unexpected pitting. No early wear. Just steady protection that feels as solid at the beginning of the season as it does at the end. Replacement is quick and clean, and the fitment is tight and secure thanks to Mercury’s factory-matched design. When you pair that with the durability of aluminum in mixed-water environments, you end up with a component that’s dependable in every sense of the word.

Why Buy OEM

When it comes to corrosion protection, “close enough” really isn’t. Genuine Mercury anodes are engineered with exact materials and weight so they erode at the right rate—fast enough to protect your engine, slow enough to stay effective. Aftermarket versions don’t always match that balance. Choosing OEM means fewer surprises during mid-season inspections, longer component life, and fewer repairs eating into your boating time. It’s the kind of choice seasoned boaters make without thinking twice.

FAQ

Q1: Which engines does the 8M0137344 Anode fit?

It fits Mercury EFI 9.9–20 horsepower FourStroke engines from 2017 and newer (serial number 0R833820 and above).

Q2: What makes this anode better than aftermarket options?

It’s made with the exact aluminum composition and dimensions Mercury specifies, ensuring proper erosion and full corrosion protection.

Q3: How can I confirm it’s the correct replacement?

Match your serial number and model, or check your owner’s manual for exact anode placement.

Q4: Can it be used in saltwater and freshwater?

Yes—the aluminum formulation performs well in both environments, including brackish water.

Q5: Is installation straightforward for most boat owners?

Very. Most people can replace it using basic hand tools during routine maintenance.