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Sierra 18-3611 Johnson/Evinrude Outboard Thermostat Kit

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

18-3611
08/05/2036 12:13 AM
Sale Price

$35.59

In Stock (9)

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Usually delivered within 2 days

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Fitment guaranteed

Product Details

The Sierra 18-3611 is a replacement thermostat kit designed for Johnson and Evinrude (J/E) outboard engines. This kit provides a reliable, OEM-quality solution for restoring proper engine temperature regulation, helping prevent overheating and ensuring optimal engine performance on the water.

Sierra is a trusted name in marine engine parts, and this thermostat kit is manufactured to meet or exceed original equipment specifications. Proper thermostat function is critical to outboard engine longevity — a faulty thermostat can cause the engine to run too hot or too cold, leading to accelerated wear and reduced efficiency.

Key Features:

  • Direct replacement for Johnson and Evinrude outboard engines
  • Meets or exceeds OEM specifications for fit, form, and function
  • Helps regulate engine operating temperature for optimal performance
  • Complete kit includes thermostat and necessary gasket/sealing components
  • Manufactured by Sierra, a leading supplier of marine engine parts
  • Corrosion-resistant materials suited for freshwater and saltwater use

Sierra Part Number: 18-3611. This kit is a cost-effective maintenance solution for keeping your Johnson or Evinrude outboard running at the correct operating temperature.

User friendly site and fantastic prices!!!

Good deals

fast

Good parts, good prices

Entered promo code wt10 for 10% off and free shipping and it didn't process when I checked out

So far the transaction was smooth. Look forward to receiving my order.

I found what I needed at a good price and checkout was easy.

great product shipping Took longer than I would have wanted but overall I guess I want in a hurry for the part

Very quick service and prompt shipping.

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