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Quicksilver 863457A2 MerCruiser Thermostat Housing Assembly

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

863457A 2
09/12/2036 10:32 AM
Sale Price

$395.47

In Stock (9)

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Usually delivered within 2 days

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Product Details

The Quicksilver 863457A 2 is a genuine OEM thermostat housing assembly designed for MerCruiser MPI sterndrive engines. As a factory-original Quicksilver part, it ensures a precise fit and reliable performance, meeting the same standards as the components installed at the factory.

This thermostat housing plays a critical role in the engine cooling system, sealing and directing coolant flow through the thermostat to maintain proper operating temperature. Replacing a cracked, corroded, or leaking housing with a genuine OEM unit helps prevent overheating and protects the engine from costly damage.

What's Included:

  • Thermostat Housing Assembly
  • Thermostat Gasket (27-8M0204687) — Qty: 1
  • Thermostat Housing Gasket (27-530451) — Qty: 1
  • Plug (22-8M0180565) — Qty: 3

Compatible Engine Applications:

  • MCM/MIE 4.3L MPI
  • MCM/MIE 5.0L MPI
  • MCM/MIE 350 Mag MPI
  • MCM/MIE MX 6.2L MPI
  • Compatible with both 1-point and 3-point drain systems

Part Numbers & Cross-References:

  • Mercury/Quicksilver OEM: 863457A 2 / 863457A2
  • Recmar Marine equivalent: RM863457A2, MAR457A2

Backed by Mercury Marine's standard factory warranty against defects in materials and workmanship, this genuine Quicksilver replacement part is the correct choice for a professional-quality repair on your MerCruiser sterndrive.

Good

Good

Cheaper than going through alta

Easy to find product and to check out.

Made an order and 2 days later got an email saying it was canceled. Picked up the phone and it was resolved quickly. Product is now in the mail. Prices are great.

Prompt shipping, good prices. Will buy from again

A+++++

quick and easy

Quick and easy

very E-Z to navigate this site.

It was quick and easy to purchase and very easy to find the item I was looking for

Item arrived in good condition and in a timely manner.

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