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Sierra 118-99397 CDM Trigger for Mercury Outboard Engines

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

118-99397
09/11/2036 1:26 AM
Sale Price

$183.24

1 left at this price

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Usually delivered within 2 days

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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 118-99397 is a replacement CDM (Capacitor Discharge Module) Trigger designed for Mercury outboard engines. Also known by the cross-reference number 18-99397, this ignition trigger precisely signals the CDM module to fire the spark plug at the correct moment in the engine's firing cycle, ensuring reliable ignition timing and optimal engine performance.

Sierra is a trusted name in marine aftermarket parts, manufacturing ignition components built to meet or exceed OEM specifications. This CDM trigger is engineered for a direct-fit replacement, making installation straightforward and dependable for marine technicians and boaters alike.

Key Features:

  • Direct replacement CDM trigger for Mercury outboard engines
  • Meets or exceeds OEM specifications for fit, form, and function
  • Critical ignition system component for proper spark timing
  • Cross-references Sierra part number 18-99397
  • Manufactured by Sierra, a leading marine aftermarket parts supplier

Restoring proper ignition function is essential to engine reliability on the water. The Sierra 118-99397 CDM trigger delivers the quality and precision needed to keep your Mercury outboard running at its best.

wonderful product

Easy peasy - Found what I wanted with free shipping.

Fast and great customer service

just placed the order, ask me later

This item will be very helpful.

Had what I needed in stock and shipped it out quickly. Would have been nice to have the option to ship on my account and get it sooner. Overall good experience and I will come back if I need similar items.

I placed my order and it was received in two days. The price was best I found on internet. Shipping was priced fairly.

Was grate, the only a prefer no charge for the delivery on regular shipment

Awesome experience, next level customer support.

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