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Sierra 18-3621 Thermostat Kit for Volvo Penta 3.0L Marine 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

18-3621
06/01/2036 1:58 PM
Sale Price

$28.47

In Stock (10+)

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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 18-3621 Thermostat Kit is a premium replacement thermostat assembly designed for Volvo Penta 3.0L marine engines and OMC Cobra stern drives. This complete kit features a temperature rating of 160°F (71°C) for reliable engine temperature control and optimal cooling system performance.

Complete Kit Includes:

  • 18-3558 Thermostat (160°F rating)
  • 18-0164 Thermostat Housing Gasket
  • Mercruiser Stern Drive 25-805063 O-Ring

Key Features:

  • Meets or exceeds the original equipment part it replaces
  • Premium-quality construction for extended service life
  • Direct replacement for OEM parts 3853799, 982554, and 3852096
  • Precision-engineered to maintain proper operating temperature

This thermostat kit provides everything needed for a complete thermostat replacement on compatible Volvo Penta 3.0L GL, GLP, GLM, GSP, and GSM engines from 1996 to current models. Sierra marine parts are manufactured to strict quality standards to ensure reliable performance in demanding marine environments.

Products specifications

Description

160°

Quick and easy so far

great prices they have , shipping is fast ---only they don't provide tracking # .<br> hope ...with time they will get better with tracking #'s.

Can't wait to see how it fits. Thanks

Fast and Easy. kinda hoping the shipping will do the same even though im went cheap for choosing free ship

None

easy to find, reasonable price, holley 2 barrel carburetor

Thanks

Good so far, but all that I've done is place the order and pay for the equipment.

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Awesome selection, most reasonable prices around!!!

easy shopping - fast check out ==== THANK YOU

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