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Sierra 18-2917-9 Marine Thermostat Housing Gasket 2-Pack

Manufacturer

Sierra

<h3>Sierra: Six Decades of Marine Aftermarket Excellence</h3><p><strong>Sierra</strong> has spent nearly 60 years earning its reputation as one of the most trusted names in the marine aftermarket industry. Originally focused on engine and drive components for boats, the brand has grown into a comprehensive source for nearly everything a boater needs to keep their vessel running at its best — from precision instrumentation to complete engine rebuild hardware.</p><p>Now operating as a brand of Dometic, Sierra manages global aftermarket distribution from a 300,000 sq. ft. facility in Litchfield, Illinois. The Sierra brand today encompasses not only its flagship marine parts line but also well-established marine names like Shields and Moeller, offering boaters a broader catalog than ever before. Whether you own an outboard, inboard, or sterndrive, Sierra's engineering team designs products to meet or exceed OEM specifications.</p><h3>Precision Instrumentation You Can Trust on the Water</h3><p>One of Sierra's most recognized product areas is its marine instrumentation lineup. The brand's <a href="/7570-sierra-gauge-set-1480">gauge sets</a> cover everything from classic analog instrument clusters to advanced digital multi-function displays. Sierra offers packages suited to outboards, sterndrives, and gasoline-powered inboards, with options ranging from coordinated analog kits in styles like Arctic, Eclipse, and Amega to modern touchscreen solutions like the R3 multi-function gauge. Features such as scratch-resistant domed glass lenses, silicone-dampened pointers, and perimeter backlighting make these instruments highly readable in all conditions.</p><p>Behind every accurate gauge reading is a properly calibrated sending circuit. Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> are a critical part of that chain, ensuring the signals from sensors and sending units are correctly interpreted by your instruments. These components are built to marine-grade standards to resist moisture, vibration, and corrosion — the realities of life on the water.</p><h3>Engine Internals Built to OEM Standards</h3><p>Sierra's history in marine power is perhaps best demonstrated by its deep catalog of engine components. The brand's <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> cover a wide range of outboard and inboard applications and are engineered to deliver reliable seals in the demanding thermal and chemical environment of a marine engine. For boaters performing seasonal overhauls, top-end rebuilds, or full engine restorations, Sierra gasket kits are a go-to resource trusted by professional marine technicians and DIY boaters alike.</p><h3>A Complete Marine Parts Partner</h3><p>Beyond instrumentation and engine internals, Sierra's catalog spans fuel systems, electrical supplies, steering components, shore power, and more — all covered by what the brand calls an industry-leading warranty. Sierra also maintains a comprehensive parts-finder tool that enables cross-referencing with OEM part numbers from major manufacturers including Mercury, Yamaha, Suzuki, Volvo Penta, and others, making it straightforward to find the right replacement part for virtually any application.</p>

Part Number

118-2917-9
09/12/2036 11:47 AM
Sale Price

$6.94

In Stock (5)

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Usually delivered within 2 days

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Fitment guaranteed

Product Details

The Sierra 18-2917-9 marine thermostat housing gasket is a high-quality replacement gasket designed specifically for MerCruiser and OMC marine engines. This gasket pack includes two paper gaskets that create a reliable seal between the thermostat housing and the engine block, preventing coolant leaks and maintaining proper engine temperature.

Key Features:

  • Constructed from premium paper gasket material for durability and heat resistance
  • Designed to meet or exceed OEM specifications for precise fitment
  • Fits MCM/MIE GM V-6 and V-8 engines including 305 and 350 cubic inch displacement models
  • Compatible with OMC and Cobra stern drives
  • Package includes 2 gaskets for convenience

OEM Cross-References: Replaces MerCruiser 27-53045, 27-530451, 27-53045B1; OMC 3701777, 312797; GM 3701777; Mallory 9-60007, 9-60007-10; GLM 31560. Sierra Marine products are manufactured to meet or exceed original equipment requirements, ensuring reliable performance and long service life for your marine engine.

Got what I ordered proptly

Fast shipping

Took a little bit to get shipped but other than that good experience.

quick and easy great price

Nice n easy

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