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Sierra 18-55505 Outboard Starter for Mercury 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

18-55505
05/31/2036 6:41 PM
Sale Price

$210.78

1 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 18-55505 is a high-performance permanent magnet gear reduction starter designed specifically for Mercury Marine outboard engines. This reliable replacement starter features advanced permanent magnet technology that delivers consistent starting power while reducing weight compared to traditional field coil starters.

Key Features:

  • Permanent magnet gear reduction design for reliable performance
  • 6:1 gear reduction ratio provides optimal cranking torque
  • Engineered specifically for Mercury Marine outboard applications
  • Lightweight construction reduces overall engine weight
  • Direct replacement for OEM Mercury starter

Sierra Marine parts are manufactured to meet or exceed OEM specifications, ensuring dependable performance and long service life. This starter is designed for easy installation and provides the cranking power needed for reliable engine starts in all conditions.

Products specifications

Application

50-8M0142679, 50-8M0061073, 50-8M0096343, 50-8M0137789

Was a perfect fit. I was surprised how hard it was to find the part but autoplicity had it.

quick and easy to order

Quick and easy. Only issue is that the shipping fee is outrageous, but might not be their fault.

First time shopper

So far so good

So far my shopping experience is excellent, I actually google searched the item I wanted to buy and browsed a few google pages before coming across this website. Once I was on thmotorsports however it was easy to navigate and select the vehicle I needed the parts for. Only wish the picture showed the parts for my selected vehicle for comparison purposes and too see exactly what would be in the kit that is specific to my vehicle, however, very satisfied so far

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