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Sierra 18-6436 Counter-Clockwise Rotation Starter Motor for Mercury/Mariner Outboard

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

18-6436
09/11/2036 9:19 AM
Sale Price

$231.44

1 left at this price

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Usually delivered within 2 days

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Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-6436 is a counter-clockwise (CCW) rotation starter motor engineered as a direct replacement for Mercury and Mariner 4-stroke outboard engines. Built to meet or exceed OEM performance standards, this PMDD-type starter delivers reliable cranking power in demanding marine environments.

Key Features:

  • Counter-clockwise (CCW) rotation — correct for Mercury/Mariner 4-stroke applications
  • 12-volt PMDD (Permanent Magnet Direct Drive) starter design
  • 9-tooth metric drive gear with 28.4mm (1.118 in) pinion OD
  • Epoxy powder-coated housing for maximum corrosion resistance in saltwater and freshwater environments
  • Meets SAE J1171 Marine Ignition Protection certification standards
  • 8mm unthreaded mounting ears for straightforward bolt-in installation
  • Engineered to meet or exceed original equipment manufacturer (OEM) specifications

OEM Cross-Reference / Replaces:

  • Mercury Marine: 50-859171T, 50-834749, 50-898265001
  • Arco Marine: 5362
  • Johnson Electric: 10153540, 6743240, SM67432
  • United Technologies: 6743240-M030SM, 6743240MO30SM

The Sierra 18-6436 is a dependable, corrosion-resistant replacement starter that installs directly in place of the original Mercury or Mariner unit, restoring reliable engine starting performance.

Products specifications

Compatibility

Fits 40HP Italy 4 Stroke 0G760300 & Up45HP Bodensee 0G760300 & Up50HP 4 Stroke 0G760300 & Up50HP Bigfoot 4 Stroke 0G760300 & Up. Replaces Mercury 50-859171T50-83474950-898265001.

Type

Starters

I expect everything to be ok. Hopefully, this will be a wonderful shopping experience.

Great

Quick and easy to use...Hopefully it's the right belt (Gates truflex #0210). Thanks!

good

Good

fast

Extremely easy and the best price by far.

Ordering went smooth!

Easy to use website. Could use more detail on items. I had to get fit requirement from maker.

extremely simple process

Best price that I could find. It was real easy to order. Placed order on wed received it on Friday, doesn't get much better than that. Product looks great! <br>3/16/2012<br>Ok, product was to big for my setup needed to exchange for smaller product. They are going to charge me a restocking fee of 15% Even when my product did not fall under their conditions. This is crap. False advertisement. I was ok with paying all the extra shipping fees which will be about the amount of the product when it was all said and done. So mad don't think I'm gonna mess with this company anymore. They don't practice what they preach. Beware :(<br>3/20/2012<br>OK, Update number 3.<br>Received E-mail today saying that Autoplicity would now Not Charge Me a 15% restocking fee and they were sorry for the inconvenience. Very Happy Now this is the way to do business. <br>Thanks Rob :)<br>3/21/2012

Sweetest price on this K&N Filter anywhere! Shipped within 24hrs too. I'm coming back to shop for my car next.

Easy so far first time buyer

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