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Sierra 18-99391 Timer Base for Johnson/Evinrude V6 Loop Charged Outboards

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

118-99391
06/04/2036 5:32 PM
Sale Price

$388.92

In Stock (5)

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Product Details

The Sierra 18-99391 Timer Base is a precision ignition component designed for Johnson and Evinrude V6 loop charged outboard engines. This critical engine management part controls ignition timing by working in conjunction with the power pack to deliver spark to the cylinders at the precise moment needed for optimal engine performance.

Application:

  • 1988-2001 Johnson/Evinrude 185, 200, 225, and 250 HP models
  • V6 loop charged engines with Quick Start and S.L.O.W. (Speed Limiting On Water) systems
  • 3.0L V6 Sea Drive models from 1988-1990

Key Features:

  • Premium quality construction for extended service life
  • Meets or exceeds OEM manufacturer specifications
  • Includes white glide ring and mounting hardware
  • 4-pin Amphenol connector for power pack connection
  • Professional-grade replacement for worn or faulty timer bases

OEM Replacement Numbers: Replaces Johnson/Evinrude part numbers 583533, 584586, 763775, and 778353. Also interchanges with CDI Electronics 133-3533.

This timer base is backed by Sierra's limited lifetime warranty and is engineered to restore reliable ignition performance on compatible Johnson and Evinrude outboard motors. Professional installation by a qualified marine technician is recommended for proper timing and optimal engine operation.

Item arrived faster than previously anticipated as it was on back order. Very happy

Thank you

Enjoying the product but the dividers in the box were difficult to put in, and didn't fit well.

Easy to order, great price and fast shipping. Great first buying experience.

Nice and ez

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