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Sierra 18-3653 Marine Thermostat Kit for OMC Sterndrive

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

118-3653
06/01/2036 1:34 AM
Sale Price

$24.33

4 left at this price

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Usually delivered within 2 days

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No Hassle Returns

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Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3653 is a complete marine thermostat kit designed for OMC sterndrive applications. This comprehensive kit maintains optimal engine operating temperature at 160°F (71°C), making it ideal for OMC Cobra V6 and V8 engines ranging from 3.8L to 7.5L displacement.

Complete Kit Includes:

  • 18-3554 Thermostat (160°F rating, 1.5-inch diameter)
  • 18-2858 Thermostat Housing Gasket
  • 18-2947 Thermostat Gasket
  • 18-0929 Thermostat Gasket
  • 18-0398 Thermostat Gasket
  • 18-7170 O-Ring

This kit provides all necessary gaskets and seals for various housing configurations, ensuring a proper installation without additional parts purchases. The 160°F thermostat is specifically calibrated for raw-water and fresh-water cooled marine engines, helping prevent overheating while ensuring the engine reaches proper operating temperature for efficient performance and reduced engine wear.

Application: Designed for OMC sterndrive models from 1992 and earlier, excluding 2.5L and 3.0L engines from 1980 and later. Compatible with a wide range of OMC Cobra engines from 90 to 454 horsepower, covering models from the late 1960s through the early 1990s.

OEM Cross-Reference: Replaces OMC 383307, 379754, 3852216; GLM 13430; and Mallory 9-43156. Sierra marine parts are engineered to meet or exceed original equipment specifications for reliable performance in harsh marine environments.

These were long enough, unlike the first ones I ordered. Six foot doesn't do the job for even the smallest boats.

Product was easy to find and what I wanted. The whole process was seamless. I love the free shipping but also the option to pay a little and get it out faster which this time I needed.

Good roce fast shipping no problems! Best kind of transaction.

SUPER EASY &amp;amp; great price assuming tires arrive on time as advertised

Very quick checkout

It was quick and easy

Thank you, perfect

Only issue I had was on the credit card statement, was confusing to have an order from Autoplicity.

Prices are competitive and I know being a repeat customer I am going to get a quality product that has not been misrepresented. It's a pleasure doing business with a reputable company.

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