My Account
Shopping Cart

Sierra 18-99423 Timer Base for Johnson Evinrude V6 Outboard Engines

Manufacturer

Sierra

<h3>Sierra Marine: Over 58 Years of Aftermarket Excellence</h3><p><strong>Sierra</strong> has built a reputation as one of the most trusted names on the water, bringing more than five decades of engineering expertise to the marine aftermarket. <a href="/7570-sierra">Sierra</a> is a globally recognized manufacturer with a rich 58-year history developing aftermarket engine and drive parts primarily for the marine industry — covering everything from inboard sterndrive applications to outboard engines across a huge range of makes and models.</p><p>In 2022, the Sierra brand underwent a significant expansion, broadening its portfolio to serve both the boating sector and select land-based applications. Today, Sierra encompasses its full core product lineup alongside well-established marine brands like Shields and Moeller, giving boaters a single trusted source for a comprehensive range of parts and supplies.</p><h3>Instrumentation Built for the Helm</h3><p>Sierra is perhaps best known for its industry-leading marine instrumentation. The brand offers one of the widest selections of <a href="/7570-sierra-gauges-200483">marine gauges</a> available in the aftermarket, spanning both analog and digital formats. Whether you need a replacement fuel level indicator, oil pressure gauge, water temperature monitor, or voltmeter, Sierra engineers these instruments to deliver accurate, reliable readings in demanding on-water conditions. All gauges are built to be water-resistant, UV-protected, and corrosion-resistant — critical traits in a saltwater or freshwater marine environment.</p><p>For boaters who want a coordinated helm setup, Sierra's <a href="/7570-sierra-gauge-set-1480">gauge sets</a> make it easy to monitor all key performance metrics in a cohesive, matched style. Available in a variety of series — from the classic Lido and Amega styles to more modern configurations — these multi-function sets cover everything from RPM and speed to fuel level and trim angle in a single package.</p><p>One of the most critical instruments on any vessel, the <a href="/7570-sierra-tachometer-gauge-1488">tachometer gauge</a> tells the operator exactly how hard the engine is working. Sierra's tachometer lineup spans a wide RPM range and is designed to interface with outboard, inboard, and sterndrive gas engines. With features like scratch-resistant lenses, perimeter lighting for night visibility, and compatibility with NMEA 2000 systems on select models, Sierra tachometers are a go-to upgrade or OEM replacement for serious boaters.</p><h3>Marine Engine Oils Formulated for the Water</h3><p>Beyond instrumentation, Sierra produces a full line of <a href="/7570-sierra-engine-oil-12138">marine engine oils</a> developed specifically for the rigors of boat engine operation. From 4-stroke FC-W certified oils to full synthetic and semi-synthetic blends in a range of viscosities, Sierra's lubricants are formulated to meet or exceed the requirements of leading marine engine manufacturers. Their engine oils are engineered to reduce friction and sludge buildup, provide maximum corrosion protection, and keep engines running cleanly — whether you're navigating coastal waters or freshwater lakes.</p><h3>Why Boaters Trust Sierra</h3><ul style="list-style:disc"><li>Over 58 years of marine aftermarket manufacturing experience</li><li>Products meet or exceed OEM standards across inboard, outboard, and sterndrive applications</li><li>Industry-leading warranty on instrumentation and parts</li><li>Comprehensive catalog spanning instrumentation, engine parts, fuel systems, and electrical supplies</li><li>Expanded brand portfolio including legacy names Shields and Moeller</li></ul>

Part Number

18-99423
09/17/2036 1:13 AM
Sale Price

$345.62

In Stock (10+)

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 18-99423 Timer Base is a premium quality ignition component designed for Johnson and Evinrude 6-cylinder outboard engines. This timer base is a critical part of the electronic ignition system, working in conjunction with the power pack to control ignition timing and ensure proper engine performance.

Key Features:

  • Designed for 1979-1988 Johnson/Evinrude 150, 155, 175, 185, 200, and 235 HP V6 engines
  • Fits cross-flow engines equipped with twin power packs
  • Premium quality construction for extended service life
  • Meets or exceeds OEM manufacturer specifications
  • Includes white glide ring and necessary installation hardware
  • Features 4-pin Amphenol connector for power pack connection

OEM Replacement: This Sierra timer base directly replaces BRP part number 583377 (also 778472) and CDI part number 133-3377. It also supersedes OEM numbers 581985, 582122, 582356, 582357, 582371, 582394, 583129, and 584558.

Sierra marine ignition components are manufactured to rigorous quality standards and are backed by Sierra's limited lifetime warranty. Professional installation by a qualified marine technician is recommended for proper timing and system integration.

No omment

It was exactly what we wanted. Excellent product.

It was what I needed, and worked perfectly, great price

Excellent quick delivery

Simple and seamless process. Great experience.

you have to give the runner 90 feet

It was easy.

None

very good / pleasant experience overall - happily surprised by the fast delivery

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