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Sierra 18-3186 Impeller Wear Plate for Yamaha Outboard Water Pump

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

18-3186
09/11/2036 6:32 PM
Sale Price

$9.72

1 left at this price

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Usually delivered within 2 days

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Product Details

The Sierra 18-3186 is a replacement impeller wear plate designed for Yamaha outboard engine water pump systems. This hard-wearing plate sits beneath the impeller inside the water pump housing, providing a smooth, durable surface that protects the pump assembly and helps maintain consistent water flow for proper engine cooling.

Key Features:

  • Durable construction engineered to withstand continuous marine use
  • Non-corrosive finish resists the harsh saltwater and freshwater environments
  • Hard-wearing surface extends the service life of the impeller and pump assembly
  • Meets or exceeds OEM specifications for a direct, reliable fit
  • Sold as a single wear plate

OEM Interchange:

  • Yamaha Outboard: 63D-44323-00-00

The Sierra 18-3186 impeller plate is also included as a component in Sierra water pump repair kits such as the 18-3415. Sierra is a trusted aftermarket manufacturer with decades of experience producing marine engine and drive components that meet or exceed original equipment standards. Replace this wear plate during routine impeller service to ensure optimal water pump performance and prevent engine overheating.

Great transaction. Like the part that they let you know if it's in stock. I was surprised at the FAST shipping of my order. The web site suggested it would be delivered on Friday after a Friday order was placed. It actually was delivered on Wednesday, two days prior to the estimated delivery time. Very well pleases with this company and will do business with them again when the need arrives.

First time and liked it.

My experience has been a real pleasure.

Only place I was able to find this product

Thank you for creating a quick and easy website and solution to my problem with an affordable price

Love the prices will come back again

Good

Easy ordering. Lightning fast delivery!

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