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Quicksilver 648771 Poppet Valve Diaphragm for Mercury & Mariner Outboards and MerCruiser Engines

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

64877 1
09/12/2036 11:16 AM
Sale Price

$8.61

In Stock (7)

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Fitment guaranteed

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Product Details

The Quicksilver 648771 Poppet Valve Diaphragm is a genuine OEM replacement part designed to keep your engine's cooling system operating correctly. The poppet valve diaphragm regulates cooling water flow and pressure through the engine — a critical function for preventing overheating and maintaining long-term engine health. When this diaphragm wears out or cracks, symptoms can include fluctuating water pressure or an engine that runs hotter than normal.

Manufactured to Mercury Marine's original equipment specifications, this Quicksilver part ensures a precise fit and reliable performance. It is constructed from flexible, marine-grade rubber engineered to withstand heat, saltwater exposure, and continuous pressure cycling.

Key Features:

  • Genuine Quicksilver OEM replacement poppet valve diaphragm
  • Compatible with select 75–250hp Mercury and Mariner 2-stroke and 4-stroke outboards
  • Fits L6 Verado outboards and various MerCruiser sterndrive and inboard engines
  • Molded to factory specifications for proper sealing and water flow
  • Serviceable with common shop tools
  • Poppet valve diaphragm only — additional parts required for full service are sold separately

Quicksilver parts are produced to match Mercury Marine's stringent OEM performance standards, ensuring the same dependable cooling and protection your engine had from the factory. Consult your owner's manual or service manual for specific application information and installation instructions.

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good price easy to find part. will see if quality is good when parts arrive.

SO FAR SO GOOD

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GLAD YOU HAVE IT IN STOCK

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live inventory is great... if it's true

Very easy using website

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