My Account
Shopping Cart

Sierra 118-5743-1 Mercury Mariner Outboard Voltage Regulator

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

118-5743-1
06/01/2036 12:41 AM
Sale Price

$149.00

2 left at this price

delivery box

Usually delivered within 2 days

free shipping

FREE SHIPPING

Authorize Seller Badge
No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-5743-1 Voltage Regulator is a premium aftermarket replacement designed for Mercury and Mariner outboard motors equipped with 16-amp or 40-amp charging systems. Engineered to meet or exceed original equipment specifications, this regulator is a reliable, direct-fit solution for maintaining proper electrical output and protecting your onboard electronics.

Key Features:

  • Compatible with Mercury and Mariner outboard engines with 16-amp or 40-amp charging systems
  • Fits model years 1992 to present
  • Meets or exceeds OEM performance standards
  • Built to withstand the harsh marine environment
  • Note: Black wire connects to engine ground

Replaces These OEM & Aftermarket Part Numbers:

  • Mercury/Mariner: 815279-3, 815279-5, 815279T, 830179T, 8301792, 854515, 854515T1, 856748, 883072T, 8M0084173
  • CDI: 194-5279
  • Mallory: 9-17101

Sierra is a leading supplier of aftermarket marine engine and drive parts, trusted by OEM engine manufacturers and boat builders alike. The Sierra 18-5743-1 voltage regulator delivers the consistent charging performance your Mercury or Mariner outboard demands.

Quick easy checkout

Incredibly easy to find the part and price is great.

Great Transaction!!! Thanks

Easily found what I was looking for.

Easy ordering...clear reading website

easy site to navigate

Needed a diesel fuel cap. Ordered it on a Saturday and received it the following Monday.

Share icon
Return Policy
Returns are easy at Boatplicity

Not happy with a purchase? No problem. We've made returning items as easy as possible. And most purchases can be returned for free for 30 days. Learn more about our Returns Policy