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Quicksilver 668631 Marine Engine Mounting Screw 3/8"-16 x 2.5"

Manufacturer

Quicksilver

<h3>Quicksilver: The Marine Enthusiast&apos;s Trusted OEM Brand</h3><p>For boaters who refuse to compromise on quality, <strong>Quicksilver</strong> has been the benchmark for marine parts, accessories, and engine care products since 1950. Based in Fond du Lac, Wisconsin, Quicksilver operates as the parts and accessories brand of Mercury Marine — and that heritage is central to everything it makes. As the only marine aftermarket brand manufactured and recommended by an original-equipment manufacturer, Quicksilver brings factory-level engineering directly to boat owners, professional technicians, and weekend warriors alike.</p><p>What sets Quicksilver apart from generic aftermarket suppliers is its direct lineage to the engineers who designed the engines in the first place. Every component is engineered, tested, and manufactured with the same exacting standards as the original equipment it replaces. The result is a product line that fits right the first time and delivers the reliability boaters depend on — whether they&apos;re navigating calm inland lakes or pushing through demanding saltwater conditions.</p><p>Quicksilver&apos;s catalog spans more than 40,000 parts across 12 product lines, covering outboard and sterndrive engines from Mercury, Mariner, Yamaha, Honda, Evinrude, Johnson, Suzuki, and more. Among the most critical components in that lineup are Quicksilver Fuel Pumps, which are built to deliver factory fit and consistent fuel delivery across a wide range of outboard applications. Reliable fuel delivery is the foundation of engine performance, and Quicksilver&apos;s fuel system components are engineered to handle the demanding conditions of marine use — including compatibility with current fuel formulations.</p><p>Beyond fuel systems, Quicksilver is a go-to source for Propeller Parts &amp; Accessories that help boaters maintain and optimize their propulsion systems. From hub kits that protect both prop and gearcase to installation hardware and prop tools, these components are designed to the same tolerances as the drives they support. Proper propeller maintenance is one of the most impactful things a boat owner can do for performance, efficiency, and engine longevity — and Quicksilver makes that job straightforward.</p><p>The brand&apos;s commitment extends across lubricants, impellers, thermostats, anodes, fuel filters, oil filters, maintenance kits, and complete service packages — all engineered for the marine environment and tested to meet or exceed the standards of major engine manufacturers. Whether you&apos;re performing routine seasonal maintenance or tackling a more involved repair, Quicksilver provides the parts that restore your engine to peak operating condition.</p><ul style="list-style:disc"><li>OEM-backed engineering from Mercury Marine</li><li>Compatible with Mercury, Yamaha, Honda, Evinrude, Johnson, Suzuki, and Mariner engines</li><li>Over 40,000 parts spanning 12 product lines</li><li>Formulated and tested for freshwater and saltwater environments</li><li>Trusted by DIY boaters and professional marine technicians since 1950</li></ul><p>When reliability on the water is non-negotiable, Quicksilver delivers the peace of mind that only a true OEM-backed brand can provide.</p>

Part Number

668631
09/11/2036 5:14 PM
Sale Price

$3.12

In Stock (10+)

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Usually delivered within 2 days

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Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Quicksilver 668631 is a genuine OEM marine-grade screw designed for Mercury Marine and MerCruiser engine applications. This precision-engineered fastener features 3/8"-16 threading and measures 2.5 inches in length, providing secure mounting for various engine components and assemblies.

Key Features:

  • Genuine Mercury Marine/Quicksilver OEM part, not aftermarket
  • Specifications: .375-16 thread x 2.500 inch length (3/8"-16 x 2.5")
  • Marine-grade construction for corrosion resistance in saltwater and freshwater environments
  • Precision-manufactured to factory specifications for proper fit and function
  • Direct replacement part for Mercury and MerCruiser outboard and sterndrive engines

Quicksilver fasteners are built to the same exacting standards as original equipment, ensuring reliable performance and durability in demanding marine conditions. When servicing or repairing your Mercury Marine engine, using genuine Quicksilver parts maintains the integrity and performance of your investment.

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