Mercury – Composite Carburetor Float | Fuel System | Marine Composite | 8673

Overview

If you have ever dealt with a carbureted outboard that refuses to idle right or keeps flooding when you least expect it, you know how something as small as a float can change your whole day on the water. The Quicksilver 8673 Composite Float brings back that easy, predictable performance that older Mercury two-strokes are known for. There’s something reassuring about installing a part that feels purpose-built — lightweight, precise, and engineered for the rough rhythm of real boating. When your engine settles into a smooth idle after the repair, it’s one of those small victories that reminds you why OEM parts matter.

Key Features

• Replacement composite float for select Mercury 3.9–150hp 2-stroke outboards
• Lightweight composite construction resists swelling and fuel absorption
• Stable buoyancy ensures proper fuel metering
• Designed to fit seamlessly with OEM carburetor components
• Meets Mercury Marine part number 8673 specifications

Engine & Boat Compatibility

• Fits a wide range of Mercury 3.9hp, 4hp, 6hp, 9.9hp, 15hp, 25hp, 40hp, 50hp, 75hp, 90hp, and 150hp 2-stroke models
• Ideal for small inflatables, jon boats, tiller setups, center consoles, aluminum fishing rigs, and classic two-stroke runabouts
• Works with single and multi-carb configurations
• Compatible with both freshwater and saltwater applications

Performance & Practical Benefits

Carburetor floats live a hard life. They sit in fuel constantly, endure vibration, and must react smoothly to changing engine demands. When they swell, leak, or absorb fuel, the engine stumbles, loads up, or simply refuses to stay running. This Mercury Marine part restores that tight, predictable carb control you remember — clean idle, sharp throttle response, and consistent fuel delivery.

You’ll feel the improvement the first time you fire up the motor after installation. Instead of bogging or chugging, the engine settles into a steady rhythm. When you crack the throttle to get the boat on plane, it responds without hesitation. And because the float is made from high-quality composite instead of older cork-style materials, it stays stable over time. There’s no sudden failure halfway through the season and no gradual performance loss as the float absorbs fuel.

This part also installs cleanly. It doesn’t bind, stick, or require modification. The hinge, pin, and needle seat align exactly as they should, which makes servicing the carburetor feel less like a gamble and more like routine maintenance.

Why Buy OEM

Floats are one of those parts where measurements matter — even a fraction of a millimeter can change how the carburetor meters fuel. Aftermarket versions often miss those tolerances, leading to a mix that’s too rich, too lean, or unpredictable. With an OEM Mercury Marine part, you get factory-level accuracy and materials that resist fuel breakdown far better than cheaper substitutes. If you want your two-stroke to start consistently and run clean, OEM is the right call.

FAQ

Q1: Which engines does this float fit?

It fits select Mercury 3.9–150hp two-stroke outboards.

Q2: What makes this different from aftermarket floats?

Better buoyancy stability, tighter tolerances, and fuel-resistant composite materials.

Q3: How do I confirm it fits my carburetor?

Check your engine’s parts diagram or match your model/serial number to Mercury part 8673.

Q4: Can it be used in saltwater?

Yes — the composite material won’t corrode and is unaffected by marine conditions.

Q5: Is installation straightforward?

Yes, especially if you’re comfortable opening and cleaning a carburetor. Basic tools are all that’s required.