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Sierra 18-8925 Water Pump Impeller for Yamaha 300-350 HP Outboard

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

18-8925
09/12/2036 8:12 AM
Sale Price

$30.90

3 left at this price

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Usually delivered within 2 days

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Product Details

The Sierra 18-8925 is a high-quality replacement water pump impeller designed specifically for Yamaha 4-stroke V8 outboard motors. This critical cooling system component ensures proper water circulation through your engine, preventing overheating and maintaining optimal operating temperatures.

Key Features:

  • Precision-engineered for Yamaha 300 HP and 350 HP 4-stroke V8 outboard engines (5.3L displacement)
  • Direct replacement for Yamaha OEM part number 6AW-44352-00-00
  • 6-blade impeller design with 36.0mm (1.42 inch) height
  • 90.0mm (3.54 inch) overall diameter with 24.6mm (0.97 inch) shaft diameter
  • Included in water pump kit 18-3477 for complete pump rebuilds
  • Meets or exceeds OEM specifications for reliable performance

This impeller is compatible with Yamaha F300, LF300, F350, LF350, and FL350 models from 2006-2019, including all A, B, and C series variations. Regular impeller replacement is essential preventive maintenance to ensure your outboard's cooling system operates at peak efficiency. Sierra's marine-grade construction delivers durability in harsh saltwater and freshwater environments.

Products specifications

Replaces

6AW-44352-00-00

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I placed an order 12/5/11 and recieved my order before 10am the following day. Very fast, very easy to use and the best prices I've found on line.

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