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Sierra 18-6241 Magnesium Trim Tab Anode for Mercury MerCruiser & Honda Outboards

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

18-6241
09/12/2036 6:27 AM
Sale Price

$20.63

In Stock (10+)

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Usually delivered within 2 days

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No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-6241 is a high-quality magnesium trim tab anode designed specifically for fresh water applications. This aftermarket replacement anode is manufactured to meet or exceed OEM specifications, providing reliable corrosion protection for your outboard or sterndrive lower unit.

Key Features:

  • Constructed of premium magnesium for superior performance in fresh water environments
  • Direct replacement for multiple OEM part numbers including Mercury 31640, 31640A1, 31640Q4, 31640T6, and Honda 41107-ZW1-003ZA
  • Compatible with Mercury/MerCruiser R/MR/Alpha One sterndrive and transom assemblies (1983-1990 and prior), Alpha One Gen II (1991 and up), and Honda BF75-BF90 outboards (1997-98)
  • Fits Mercury 3, 4, and 6 cylinder, V6 engines
  • Designed for use with aluminum propellers in fresh water only
  • Weight: 1.21 lbs

Important: Magnesium anodes are for fresh water use only. Always verify propeller clearance after installation. For saltwater applications, use zinc anodes; for brackish water, use aluminum anodes.

Products specifications

Description

Magnesium

Fits with

Mercruiser - 31640, 31640A1, 31640 T6, 31640Q 4, Honda - 41107-ZW1-0032A

Awesome place to buy goods. I wasn't able to find the item I bought cheaper anywhere else. I will definitely buy from autoplicity again.

quick and easy

Buying was fine. Let's wait to see about fulfilling, shipping, and quality of order.

good service

Great website, easy to navigate.

good conditon! next time hopefully sooner

very easy to look up ,find item I was looking for !just wish I could of used my paypal account ,maybe next time !!! also according to information this part is supposed to fit !! Thanks

Easy to use

Quick and very easy!!!!!!!

it better fit

Ordering was easy web site easy to use

Same shipping price for larger volume is great. Thank you. www.snpspeed.com

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