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Quicksilver 18643A7 Triangular Flywheel Mount Engine Coupler Kit with Yoke for MerCruiser Alpha Stern Drives

Manufacturer

Quicksilver

<p>Since 1950, Quicksilver has been delivering premium marine parts, accessories, and lubricants that set the standard for quality and performance on the water. As the premier supplier of Mercury Marine original-equipment parts and accessories, Quicksilver occupies a unique position in the marine aftermarket industry—it's the only marine brand manufactured and recommended by an original-equipment manufacturer.</p> <h3>Engineering Excellence Backed by Mercury Marine</h3> <p>What sets Quicksilver apart from other aftermarket brands is its direct connection to Mercury Marine's engineering expertise. No aftermarket company comes close to Quicksilver's level of research and design, and literally millions of hours have been spent on fired-engine testing and analysis. This rigorous development process ensures that every component meets the exacting standards required for marine environments, where reliability isn't just a preference—it's essential.</p> <p>Quicksilver offers the widest range of premium replacement parts and lubricants for Mercury engines and drives in the marine industry, while their expertise makes Quicksilver aftermarket parts and lubricants outstanding choices to service most major marine engine brands. Whether you're maintaining a Mercury, Yamaha, Honda, or Suzuki outboard, Quicksilver provides OEM-quality solutions that fit and function like the original components.</p> <h3>Comprehensive Product Range for Every Marine Application</h3> <p>From critical propulsion components to routine maintenance items, Quicksilver covers the full spectrum of marine parts needs. Their <a href="/200836-quicksilver-propellers-quicksilver-7456">propeller selection</a> represents decades of hydrodynamic research, offering precision-engineered designs that maximize thrust, fuel efficiency, and handling across different hull configurations and engine combinations.</p> <p>For fuel system reliability, <a href="/200446-fuel-pumps-kitscarburetor-kits-quicksilver-7456">Quicksilver fuel pumps and carburetor kits</a> deliver consistent performance even in demanding marine conditions where ethanol-blended fuels and temperature extremes can compromise inferior components. The brand's <a href="/200835-quicksilver-manifoldsriserselbows-quicksilver-7456">exhaust manifolds, risers, and elbows</a> are engineered specifically to handle the corrosive marine environment, featuring materials and coatings that resist saltwater degradation.</p> <p>Cooling system maintenance becomes straightforward with <a href="/2208-engine-water-pump-quicksilver-7456">Quicksilver water pumps</a> and impeller kits designed for easy installation and reliable operation. Regular impeller replacement is one of the most critical preventive maintenance tasks for any marine engine, and Quicksilver kits include all necessary gaskets and components for professional-grade results.</p> <p>The brand's <a href="/200382-external-engine-parts-quicksilver-7456">external engine parts</a> portfolio ensures that boat owners and marine technicians can source everything from mounting hardware to trim system components with confidence in fit and durability.</p> <h3>Quality You Can Trust</h3> <p>Quicksilver has earned a loyal following by providing the highest quality products for more than 60 years, and consumers consider it one of the most trusted brands in the markets it serves. With over 40,000 parts across 12 product lines, Quicksilver products can be found throughout the world, supporting recreational boaters, commercial operators, and marine service professionals alike.</p> <p>This commitment to quality extends beyond parts to include specialized marine lubricants, fuel additives, and maintenance products formulated specifically for the unique demands of marine engines. When you choose Quicksilver, you're buying performance, protection, and peace of mind—qualities that matter when you're miles from shore or simply want to maximize your time on the water.</p>

Part Number

18643A 7
07/15/2036 5:38 AM
Sale Price

$515.73

In Stock (10+)

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Usually delivered within 2 days

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Product Details

The Quicksilver 18643A7 is a genuine OEM triangular-shaped, flywheel-mount engine coupler kit designed for select MerCruiser Alpha stern drive applications. This kit includes a yoke and is manufactured by Mercury Marine to meet original equipment specifications, ensuring a precise fit and reliable power transfer between the engine and stern drive.

The engine coupler is a critical drivetrain component that connects the engine flywheel to the stern drive input shaft. Replacing a worn or damaged coupler with a genuine OEM part helps maintain proper alignment, reduces vibration, and protects downstream drivetrain components.

Key Features:

  • Genuine OEM Quicksilver/Mercury Marine part — not aftermarket
  • Triangular flywheel-mount design with yoke included
  • Manufactured to Mercury Marine original equipment specifications
  • Direct replacement for MerCruiser Alpha stern drive applications
  • Supersedes earlier part number 18643A2

Specifications:

  • Part Number: 18643A7 (also listed as 18643A 7)
  • Mount Style: Triangular, flywheel mount
  • Includes: Coupler and yoke
  • Supersedes: 18643A2

Consult your MerCruiser service manual or parts manual to confirm the correct application before installation.

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