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Sierra 18-3535 Marine Thermostat 130°F for Mercury Outboard Engines

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

118-3535
06/02/2036 5:06 PM
Sale Price

$87.46

3 left at this price

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Usually delivered within 2 days

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Product Details

The Sierra 18-3535 is a premium marine engine thermostat designed specifically for Mercury outboard applications. This replacement thermostat features a 130°F (54°C) opening temperature rating and is constructed from durable plastic and steel materials engineered to withstand the harsh marine environment.

Key Features:

  • 130°F (54°C) temperature rating for optimal engine cooling performance
  • Plastic and steel construction for corrosion resistance and durability
  • Exact OEM replacement designed to meet or exceed original equipment specifications
  • Standard-flow design for proper coolant circulation
  • Manufactured by Sierra, a trusted supplier with over 35 years in the marine parts industry

OEM Cross-Reference:

  • Mercury Marine 885599003
  • Mercury Marine 885599004
  • Mercury Marine 8855991
  • Mercury Marine 8M0057307

This thermostat is compatible with Mercury 200, 225, and 250 HP EFI and DFI outboard engines. Sierra products are engineered to match rigorous quality standards and provide reliable performance at a competitive price point. Each Sierra product is crafted from premium materials and designed to meet the demands of today's high-horsepower marine engines.

Very quick service - great products!! Highly recommend!

All worked out great. Fast delivery and great price.

Quality parts at a reasonable price Bang !

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