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Sierra 18-2740 Cylinder Block Gasket for Mercury Marine Outboard Engines

Manufacturer

Sierra

<h3>Sierra Marine: Over 58 Years of Aftermarket Excellence</h3><p><strong>Sierra</strong> has built a reputation as one of the most trusted names on the water, bringing more than five decades of engineering expertise to the marine aftermarket. <a href="/7570-sierra">Sierra</a> is a globally recognized manufacturer with a rich 58-year history developing aftermarket engine and drive parts primarily for the marine industry — covering everything from inboard sterndrive applications to outboard engines across a huge range of makes and models.</p><p>In 2022, the Sierra brand underwent a significant expansion, broadening its portfolio to serve both the boating sector and select land-based applications. Today, Sierra encompasses its full core product lineup alongside well-established marine brands like Shields and Moeller, giving boaters a single trusted source for a comprehensive range of parts and supplies.</p><h3>Instrumentation Built for the Helm</h3><p>Sierra is perhaps best known for its industry-leading marine instrumentation. The brand offers one of the widest selections of <a href="/7570-sierra-gauges-200483">marine gauges</a> available in the aftermarket, spanning both analog and digital formats. Whether you need a replacement fuel level indicator, oil pressure gauge, water temperature monitor, or voltmeter, Sierra engineers these instruments to deliver accurate, reliable readings in demanding on-water conditions. All gauges are built to be water-resistant, UV-protected, and corrosion-resistant — critical traits in a saltwater or freshwater marine environment.</p><p>For boaters who want a coordinated helm setup, Sierra's <a href="/7570-sierra-gauge-set-1480">gauge sets</a> make it easy to monitor all key performance metrics in a cohesive, matched style. Available in a variety of series — from the classic Lido and Amega styles to more modern configurations — these multi-function sets cover everything from RPM and speed to fuel level and trim angle in a single package.</p><p>One of the most critical instruments on any vessel, the <a href="/7570-sierra-tachometer-gauge-1488">tachometer gauge</a> tells the operator exactly how hard the engine is working. Sierra's tachometer lineup spans a wide RPM range and is designed to interface with outboard, inboard, and sterndrive gas engines. With features like scratch-resistant lenses, perimeter lighting for night visibility, and compatibility with NMEA 2000 systems on select models, Sierra tachometers are a go-to upgrade or OEM replacement for serious boaters.</p><h3>Marine Engine Oils Formulated for the Water</h3><p>Beyond instrumentation, Sierra produces a full line of <a href="/7570-sierra-engine-oil-12138">marine engine oils</a> developed specifically for the rigors of boat engine operation. From 4-stroke FC-W certified oils to full synthetic and semi-synthetic blends in a range of viscosities, Sierra's lubricants are formulated to meet or exceed the requirements of leading marine engine manufacturers. Their engine oils are engineered to reduce friction and sludge buildup, provide maximum corrosion protection, and keep engines running cleanly — whether you're navigating coastal waters or freshwater lakes.</p><h3>Why Boaters Trust Sierra</h3><ul style="list-style:disc"><li>Over 58 years of marine aftermarket manufacturing experience</li><li>Products meet or exceed OEM standards across inboard, outboard, and sterndrive applications</li><li>Industry-leading warranty on instrumentation and parts</li><li>Comprehensive catalog spanning instrumentation, engine parts, fuel systems, and electrical supplies</li><li>Expanded brand portfolio including legacy names Shields and Moeller</li></ul>

Part Number

18-2740
09/13/2036 9:50 AM
Sale Price

$18.47

In Stock (5)

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Product Details

The Sierra 18-2740 Cylinder Block Gasket is a precision-fit replacement marine gasket designed for Mercury 3-cylinder outboard engines, including the 65 Jet, 75 HP, and 90 HP configurations. This cylinder block gasket provides a reliable, leak-free seal and is engineered to meet or exceed the specifications of the original equipment part it replaces.

Key Features:

  • Direct OEM replacement for Mercury Marine 3-cylinder outboard applications
  • Meets or exceeds original equipment manufacturer (OEM) specifications
  • Manufactured to withstand the demanding conditions of the marine environment
  • Sold as one cylinder block gasket per package
  • Interchangeable with GLM part number 37660

OEM Cross-Reference Part Numbers:

  • Mercury Marine: 27-430051, 27-430052, 27-430053, 27-430055, 27-430056, 27-430057
  • GLM: 37660

Sierra International is a trusted supplier to OEM engine manufacturers and boat builders, delivering high-quality marine engine components that hold up in harsh on-water conditions. The 18-2740 is also a component found in Sierra's 18-4336 Powerhead Gasket Set for Mercury 70–90 HP 3-cylinder outboards.

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