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Sierra 18-3805 Cylinder Head Gasket for Yamaha Outboard Engines

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

118-3805
09/11/2036 7:16 AM
Sale Price

$34.80

2 left at this price

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Usually delivered within 2 days

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Product Details

The Sierra 18-3805 is a high-quality aftermarket cylinder head gasket designed specifically for Yamaha outboard motors. This precision-engineered gasket provides a reliable seal between the cylinder head and engine block, ensuring optimal compression and preventing coolant and oil leaks.

Key Features:

  • Premium aftermarket replacement for Yamaha marine outboard engines
  • Designed for 3-cylinder Yamaha 75, 80, 85, and 90 HP outboards (1984-2009)
  • Manufactured to OEM specifications for reliable fit and performance
  • Durable construction withstands high temperatures and pressures
  • Backed by Sierra's comprehensive warranty covering parts and labor

Replaces OEM Part Numbers: Yamaha 688-11181-02-00, 688-11181-A0-00, 688-11181-A1-00

Sierra Marine is a trusted market leader in aftermarket marine engine parts, offering products that cover every major engine brand with exceptional quality and customer satisfaction.

great prices easy to navigate site, free shipping, and had the part that I needed,

perfect

So Far, So Good

Fast and easy

Online experience was excellent. Site was easy to navigate. Shipping was easy to track. Delivery was on top. Quality of product was above what was expected. What else could you ask for in an online experience? Definitely will use boatplicity again. Boatplicity = Simplicity. Bottom line.

Great service, only hiccup was I paid for 2 day shipping $9.99 Item took 5 days. I was credited the $9.99 No big deal, will order from boatplicity.com again!

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So far so good ,order made

Great experience. Easy, quick, great price

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