Mercury – Black Max 3-Blade Aluminum Propeller | 12.75" Diameter x 21" Pitch | Right-Hand Rotation | 3-Blade | Aluminum | Phantom Black Finish | 77348A45

Overview

Every boater knows that feeling when everything clicks—when the engine hums, the throttle responds, and the boat lifts effortlessly onto plane. That’s the kind of connection you get with the Mercury Black Max 3-Blade Aluminum Propeller (Part Number 77348A45). It’s built for balance, for responsiveness, and for that quiet confidence you feel when your boat moves precisely the way you expect it to. Whether you’re cruising open water or threading through narrow channels, this prop delivers performance that feels natural and refined.

Key Features

• Diameter & Pitch: 12.75" diameter x 21" pitch
• Rotation: Right-Hand
• Blade Count: 3-Blade design for smooth lift and steady thrust
• Material: Patented Mercalloy aluminum alloy for strength with built-in flexibility
• Finish: Mercury Phantom Black glossy enamel for superior corrosion resistance
• Hub System: Includes Flo-Torq II Hub Kit 835257K1 to protect your drivetrain from impact damage
• Design Details: Precision-engineered for quick acceleration, consistent grip, and vibration-free cruising

Engine & Boat Compatibility

• Designed for Mercury and Mariner 40–60 HP BigFoot/Command Thrust (all years)
• Fits Mercury and Mariner 75–125 HP (1978 and newer) outboards
• Excellent fit for runabouts, pontoons, fishing boats, and light cruisers
• Perfect for boaters who want smooth cruising with solid top-end performance and fuel efficiency

Performance Benefits

The Black Max 77348A45 offers that seamless blend of power and finesse that makes boating such a pleasure. Throttle up, and you’ll feel how smoothly it grabs the water, giving you quick acceleration and efficient lift onto the plane. Once you’re up to speed, the prop stays locked in with a clean, stable feel, no slipping, no chatter, just smooth, steady thrust. The 21-pitch setup gives you great top-end speed without sacrificing midrange response, making it ideal for those who like to stretch their boat’s legs across open water.

Mercury’s Mercalloy aluminum alloy provides the perfect balance between strength and flexibility. It’s tough enough to stand up to years of use, yet forgiving enough to absorb minor impacts that would ruin a stiffer prop. The Phantom Black enamel finish resists corrosion, keeping it sharp whether you’re running freshwater lakes or salty coastal bays. With low maintenance and high reliability, it’s the kind of prop you install once and enjoy season after season.

Why is this prop a strong choice vs. alternatives?

• Mercury OEM quality: Designed and built by Mercury’s own engineers, ensuring perfect pitch, balance, and compatibility with your engine.

• Reliable and easy to maintain: Crafted for real-world boating, durable, low-maintenance, and ready for season after season of dependable performance.

• Cost-effective vs. stainless: Delivers smooth, confident handling and acceleration at a fraction of the cost of a stainless-steel propeller.

• Versatile fit across multiple setups: Ideal for a wide range of boats and outboards, offering consistent performance whether you’re cruising, fishing, or towing.

FAQ Section

Q1: Which Mercury engines does the Black Max 77348A45 fit?

It’s made for Mercury and Mariner 40–60 HP BigFoot/Command Thrust (all years) and 75–125 HP (1978 and newer) outboards.

Q2: What makes this propeller different from other Mercury options?

The Black Max stands out for its Mercalloy aluminum construction, combining durability with slight flex to handle minor impacts. Its Flo-Torq II Hub System reduces vibration and protects your drivetrain.

Q3: How do I know if this pitch or size is right for my boat?

A 21-pitch prop is excellent if you’re looking for more top-end speed and efficient cruising. Check your current prop markings or owner’s manual to confirm compatibility.

Q4: Can this prop be used in both saltwater and freshwater?

Yes. The Phantom Black enamel finish is corrosion-resistant, maintaining performance and appearance in all water conditions.

Q5: What hub system does it use?

It includes the Flo-Torq II Hub Kit 835257K1, designed to absorb shock, reduce vibration, and safeguard your prop shaft from impact damage.