Mercury – Prop Nut, Rear | V12 Contra-Rotating Prop System | Brass | 8M0176915

Overview

When you run a boat powered by a Mercury V12, you get used to a certain feeling — a steady, confident push that never seems to hesitate, even when the water turns sloppy or the load gets heavy. That confidence doesn’t come from the engine alone. It comes from every component working together, right down to the hardware holding your props in place. The Mercury 8M0176915 Rear Prop Nut is one of those pieces you rarely think about until you need it, but it’s the reason the whole drive system feels tight, smooth, and ready for whatever the day brings. Offshore, inlets, long runs to the reef — it’s one of those parts that simply does its job so you can focus on the water ahead.

Key Features

• Secures the rear propeller in a Mercury V12 contra-rotating prop system
• Built from hardened, marine-grade brass for long-term strength and corrosion resistance
• Precision-machined to handle extreme torque and load
• Engineered to exceed Mercury Marine’s factory performance and durability requirements
• Mercury Marine part number 8M0176915

Engine & Boat Compatibility

This genuine Mercury Marine part is designed for:

• Mercury 7.6L V12 600hp Verado outboards
• Mercury 7.6L V12 500hp SeaPro outboards
• Ideal for large center consoles, offshore fishing boats, heavy commercial vessels, sport cruisers, and high-end multi-engine setups

Performance & Practical Benefits

In a contra-rotating setup, the rear prop takes a tremendous share of thrust and load. That means the nut holding it in place needs to be absolutely trustworthy. With the 8M0176915 installed, the rear prop sits firm and true, eliminating wobble, maintaining perfect alignment, and delivering the tight, immediate bite the V12 system is known for.

You’ll feel it most when you push the throttles forward — that clean, steady acceleration with no vibration or lag. When you settle into a long cruise, the ride stays smooth because everything behind the transom is locked down exactly as it should be. And when you’re working in rough conditions or running a heavy hull, this brass nut keeps the prop secure without loosening or deforming under stress. It’s a small part, but on a V12, it carries a big responsibility.

Installation is straightforward and familiar for anyone used to working with Mercury hardware. Threads engage evenly, torque holds cleanly, and you can feel the quality as you tighten it into place.

Why Buy OEM

A V12 drive system isn’t a place to take shortcuts. Mercury Marine parts are engineered specifically for these engines, with metallurgy, machining tolerances, and load ratings designed around their unique torque curves. Aftermarket hardware might fit, but it won’t match the precision or the long-term reliability of a genuine Mercury Marine part.

OEM means proper fitment, predictable performance, and components that play well with the rest of your prop system. It’s the smart, practical choice for anyone who wants their engine to last — and anyone who would rather spend their weekend boating instead of troubleshooting.

FAQ

Q1: Which engines does this part fit?

It fits Mercury 7.6L V12 500hp SeaPro and 600hp Verado outboards.

Q2: Why choose this over aftermarket options?

Because Mercury OEM parts match factory torque loads, precision machining, and long-term durability standards.

Q3: How can I confirm this is the right nut for my prop setup?

Match the part number and verify compatibility using your engine’s owner’s manual or existing hardware.

Q4: Can it be used in both saltwater and freshwater?

Absolutely — marine-grade brass offers strong corrosion resistance in any environment.

Q5: Is installation straightforward?

Yes. With proper torque specs and standard tools, most boat owners can replace it easily.