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Sierra 18-21753 OMC Engine Coupler

Manufacturer

Sierra

<h3>Sierra: Six Decades of Marine Aftermarket Excellence</h3><p><strong>Sierra</strong> has spent nearly 60 years earning its reputation as one of the most trusted names in the marine aftermarket industry. Originally focused on engine and drive components for boats, the brand has grown into a comprehensive source for nearly everything a boater needs to keep their vessel running at its best — from precision instrumentation to complete engine rebuild hardware.</p><p>Now operating as a brand of Dometic, Sierra manages global aftermarket distribution from a 300,000 sq. ft. facility in Litchfield, Illinois. The Sierra brand today encompasses not only its flagship marine parts line but also well-established marine names like Shields and Moeller, offering boaters a broader catalog than ever before. Whether you own an outboard, inboard, or sterndrive, Sierra's engineering team designs products to meet or exceed OEM specifications.</p><h3>Precision Instrumentation You Can Trust on the Water</h3><p>One of Sierra's most recognized product areas is its marine instrumentation lineup. The brand's <a href="/7570-sierra-gauge-set-1480">gauge sets</a> cover everything from classic analog instrument clusters to advanced digital multi-function displays. Sierra offers packages suited to outboards, sterndrives, and gasoline-powered inboards, with options ranging from coordinated analog kits in styles like Arctic, Eclipse, and Amega to modern touchscreen solutions like the R3 multi-function gauge. Features such as scratch-resistant domed glass lenses, silicone-dampened pointers, and perimeter backlighting make these instruments highly readable in all conditions.</p><p>Behind every accurate gauge reading is a properly calibrated sending circuit. Sierra's <a href="/7570-sierra-gauge-resistor-47908">gauge resistors</a> are a critical part of that chain, ensuring the signals from sensors and sending units are correctly interpreted by your instruments. These components are built to marine-grade standards to resist moisture, vibration, and corrosion — the realities of life on the water.</p><h3>Engine Internals Built to OEM Standards</h3><p>Sierra's history in marine power is perhaps best demonstrated by its deep catalog of engine components. The brand's <a href="/7570-sierra-engine-gasket-set-5404">engine gasket sets</a> cover a wide range of outboard and inboard applications and are engineered to deliver reliable seals in the demanding thermal and chemical environment of a marine engine. For boaters performing seasonal overhauls, top-end rebuilds, or full engine restorations, Sierra gasket kits are a go-to resource trusted by professional marine technicians and DIY boaters alike.</p><h3>A Complete Marine Parts Partner</h3><p>Beyond instrumentation and engine internals, Sierra's catalog spans fuel systems, electrical supplies, steering components, shore power, and more — all covered by what the brand calls an industry-leading warranty. Sierra also maintains a comprehensive parts-finder tool that enables cross-referencing with OEM part numbers from major manufacturers including Mercury, Yamaha, Suzuki, Volvo Penta, and others, making it straightforward to find the right replacement part for virtually any application.</p>

Part Number

18-21753
09/11/2036 10:55 AM
Sale Price

$429.86

4 left at this price

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Usually delivered within 2 days

free shipping

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 18-21753 is a replacement engine coupler designed for OMC (Outboard Marine Corporation) sterndrive and inboard applications. This critical drivetrain component connects the engine flywheel to the drive unit, transmitting power while allowing for slight misalignment between the engine and drive.

Key Features:

  • Direct replacement for OMC engine coupler applications
  • Engineered to OEM specifications for proper fit and function
  • Durable construction designed to withstand marine environments
  • Essential component for maintaining proper power transfer from engine to drive

Regular inspection and replacement of the engine coupler is important for preventing drivetrain damage and ensuring smooth operation. This Sierra replacement part provides reliable performance for OMC marine engine systems.

totally satisfied!!!

Shazaaam!

very prompt in shipping my order.

Price was good, order was delivered quickly, quality of product was good. Very satisfied.

Am satisfied

Overall experience was ok. Got my items at a very great price. Cheapest I found online BUT the shipping was a slight nightmare. Had to call multiple times and items finally got to me but other than I am pleased. I ordered a few days before black Friday/cyber Monday deals so that could've been the problem too. In the end I got what I wanted at the best price!

excellent web site very easy to use and fast delivery

Good

Went smoothly

No problem

gREAT SERVICE GREAT PRICE

Great prices, fast shipping. Great order status updates.

Great so far.

found what I wanted , right price . ran it through Amazon Lifes good

They are excellent. They were able to send out my item as early as the next day. I am anticipating my product by early next week. Great!

good so far. just placed order

Simple and easy to order

Easy and cheap.

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