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Sierra 18-3648 Marine Thermostat Kit 160° for Mercruiser

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

18-3648
06/01/2036 2:33 AM
Sale Price

$24.60

In Stock (6)

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Usually delivered within 2 days

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No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3648 Marine Thermostat Kit is a complete 160-degree thermostat replacement kit designed for Mercruiser stern drive engines. Proper thermostat operation is essential for maintaining optimal engine temperature, ensuring peak performance and maximum fuel efficiency in marine environments.

Kit Includes:

  • Sierra 18-3649 Thermostat (160°F)
  • Sierra 18-2553 Thermostat Cover Gasket
  • Sierra 18-2917 Thermostat Gasket

Key Features:

  • 160-degree Fahrenheit temperature rating for precise engine temperature control
  • Marine-grade construction withstands harsh saltwater and brackish water conditions
  • Complete kit with all necessary gaskets for proper installation
  • Replaces OEM Mallory 9-43100
  • Meets or exceeds original equipment specifications

This thermostat kit is compatible with a wide range of Mercruiser engines including GM V-6 and V-8 configurations, 3.0L, 4.3L, 5.0L, 5.7L, and 350 Mag engines from various model years. Sierra marine parts are engineered to deliver reliable performance and long service life in demanding marine applications.

best price on line !!!!<br>fast shipping, highly recommended !!!!!

Fast and easy!

Had instock, good price

I was able to find the headers I was looking for at a good price and free shipping is a big plus as well.

shopping was awesome and easy , items showed in stk, but delivery was over 9 days

prices are good. After I paid it took them 5 days to ship the order. Communication is not very good with autoplicity.

Good price

Great easy

Best parts at the best price, will continue to order from Autoplicity. Shipping is also very fast.

Cheapest I found. Fast shipping time too. Haven't got to try out my products yet but I would/will refer this website to others

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