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Sierra 118-21752-1 Marine Engine Coupler for OMC Cobra & Volvo Penta

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

118-21752-1
06/02/2036 3:09 AM
Sale Price

$238.18

3 left at this price

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Usually delivered within 2 days

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FREE SHIPPING

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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 118-21752-1 is a premium aftermarket marine engine coupler designed to connect GM V6 and V8 engines to OMC Cobra and Volvo Penta SX stern drives. This critical drivetrain component features a 17-spline design and is engineered for one-piece rear main seal engines with a 3-inch crankshaft bolt pattern circle.

Key Features:

  • Direct replacement for OMC part numbers 3858437, 984290, 986120, and 3853917
  • Compatible with Volvo Penta part numbers 3853917 and 3858437
  • Engineered to meet or exceed OEM specifications
  • 17-spline design for positive engagement
  • Manufactured from quality materials for harsh marine environments

Engine Compatibility:

  • 4.3L engines (1986-1998)
  • 5.0L engines (1986-1988, 1998)
  • 5.7L engines (1986-1992, 1994, 1996-1998)

Sierra Marine is a trusted leader in aftermarket marine engine parts, delivering quality components backed by comprehensive customer satisfaction warranties. This engine coupler is essential for transferring power from your engine to the stern drive unit.

Very easy traction. Will be ordering again.

Very good service

Thanks

Fast

It was what it should be Thank You Art

As described and rapid delivery.

quick and easy great price

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

Wow, the price was unbeatable and the delivery was quick. The props came in perfect condition, couldn't be happier.

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