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Sierra 18-3217 Water Pump Impeller Kit for MerCruiser Alpha One

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

118-3217
09/12/2036 8:28 AM
Sale Price

$23.16

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 18-3217 Water Pump Impeller Kit is a comprehensive repair solution designed for MerCruiser #1, R, MR, and Alpha One stern drives through serial number D494568, as well as Mercury/Mariner 65 HP (4-cylinder) through V-6 outboards with short vane impellers. This complete kit contains all the essential components needed to properly service your marine engine's cooling system.

Complete Kit Includes:

  • Water pump impeller made from neoprene rubber compound for flexibility and durability
  • Water tube guide
  • Impeller wear plate
  • Seven (7) gaskets including water pump gaskets, base gasket, and drain screw gaskets
  • Six (6) O-rings in various sizes
  • Seal ring and grommet
  • Water pump housing bushing

This impeller kit is engineered to meet or exceed OEM specifications and is manufactured to high quality standards with proper bonding and performance testing. The neoprene impeller material provides added flexibility for long-lasting performance in harsh marine environments. Note that the pump housing is not included with this kit; if a housing is needed, order Sierra 18-3316.

OEM Cross-References: Replaces Mercury/MerCruiser 46-96148A8, 46-96148A5 (without base or housing), 46-32437A1, 46-32437A3, 46-37433A1, 46-42579A4, 46-44292A4, 46-44579A4; GLM 12290; Mallory 9-48304, 9-48310.

Great service, paid extra for quick delivery. It came the next day! WOW! Thanks!

Great parts fast shipping .

Fast

Great Deal!

easy

Best price online for quality name brand performance parts. Order processing and shipping is phenomenal! Even ordering late Friday over a weekend, they processed the order that day, it was shipped and in my hands by Tuesday morning without paying any form of expidited service.

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