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Sierra 18-3839 Head Gasket for Johnson Evinrude Outboard Engines OMC 333670

Manufacturer

Sierra

<p>For nearly six decades, Sierra has established itself as one of the marine industry's most trusted names in aftermarket engine and drive parts. Founded as a specialized marine parts manufacturer, Sierra has grown into a comprehensive supplier of replacement components, instrumentation, and accessories for both recreational and commercial boating applications. Operating from their 300,000-square-foot distribution center in Litchfield, Illinois, Sierra serves boat owners and marine technicians worldwide with an extensive catalog of parts engineered specifically for the harsh saltwater environment.</p><h3>Marine Engine Excellence</h3><p>Sierra's reputation was built on delivering precision-engineered internal engine components and drive system parts that meet or exceed OEM specifications. Their <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> provide critical sealing solutions for inboard and outboard motors, while their <a href="/7570-sierra-engine-complete-assembly-15341">engine complete assemblies</a> offer comprehensive replacement options for major overhauls. Each component undergoes rigorous testing to ensure reliability in demanding marine conditions, from corrosion resistance to temperature cycling performance.</p><h3>Instrumentation and Monitoring Systems</h3><p>Accurate instrumentation is essential for boat operators to monitor engine health and prevent costly breakdowns on the water. Sierra's comprehensive line of <a href="/7570-sierra-gauges-200483">gauges</a> includes everything from fuel pressure and temperature indicators to voltmeters and trim gauges, all designed with marine-grade materials that withstand vibration, moisture, and UV exposure. Their <a href="/7570-sierra-tachometer-gauge-1488">tachometer gauges</a> deliver precise RPM readings critical for optimizing engine performance and fuel efficiency. Supporting these instruments, Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> ensure proper signal conditioning and accurate readings across various sensor types and engine configurations.</p><h3>Expanded Product Portfolio</h3><p>In 2022, Sierra significantly broadened its scope beyond traditional marine engine parts to encompass a wider range of boating accessories and even outdoor power equipment components. This strategic expansion brought established marine brands like Shields and Moeller under the Sierra umbrella, creating a one-stop resource for marine maintenance and replacement parts. The company now offers fuel systems, electrical components, battery charging solutions, and NMEA electronics alongside their traditional engine parts lineup.</p><h3>Quality Backed by Industry-Leading Warranties</h3><p>What sets Sierra apart in the crowded aftermarket marine parts market is their commitment to standing behind every component they manufacture. Their warranty coverage extends beyond simple part replacement—it includes shop labor, haul-out fees, towing charges, and related incidental costs should a warrantied part fail. This comprehensive protection reflects the company's confidence in their manufacturing processes and quality control standards. For boat owners facing repairs far from shore or mechanics working on customer vessels, this peace of mind is invaluable. Whether you're maintaining an outboard motor, rebuilding an inboard engine, or upgrading your boat's instrumentation, Sierra's decades of marine industry experience and commitment to quality make them a reliable choice for keeping your vessel running at peak performance.</p>

Part Number

18-3839
08/23/2036 12:35 AM
Sale Price

$41.73

In Stock (6)

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Usually delivered within 2 days

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3839 is a premium aftermarket head gasket engineered as a direct replacement for Johnson and Evinrude outboard engines. Designed to seal the cylinder head to the engine block, this gasket delivers a reliable, leak-free fit in demanding marine environments.

Sierra International is a market leader in aftermarket marine engine parts, and every Sierra gasket is manufactured to meet or exceed the original equipment specifications it replaces — ensuring long-lasting performance on the water.

Key Features:

  • Direct OEM replacement head gasket for Johnson/Evinrude outboard engines
  • Meets or exceeds original equipment manufacturer (OEM) standards
  • Constructed with marine-grade materials for durability in harsh conditions
  • Sold individually (1 gasket per package)
  • UPC: 30999316905

OEM Cross-Reference Numbers:

  • OMC: 333670, 334726
  • Also replaces: 473839, GLM34590, AP2199, 963825

Easy.

Smooth &amp; easy transaction!

very good

Easy!

Great price. I will leave more feedback after it arrives and is installed.

Good

Good

Ordered a Simpson helmet on Monday afternoon, received tracking on Monday evening and will have the product on Wednesday! Quick service! Also would like to mention that the price was the lowest of anywhere I looked up.

Y'all is Awesome!

This was my first purchase from Autoplicity, and it was an excellent experience. They had the Motive brake bleeder adapter I needed at the best price I could find on the web. Shipping was prompt and the transaction was super smooth. Thanks!

Easy to order with the Amazon connectivity

Fast and easy had what I needed. Also could not find what I was looking for any where but here. Thanks

They had two items that I wanted in stock with the lowest price I've seen online anywhere, and had super affordable shipping options.

Vehicle Specific part look up was a bit off on the bilstein products. Hard to find the rears required for my truck.

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