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Sierra 18-4546 Water Pump Insert Cup for Outboard Motors

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

18-4546
09/11/2036 7:18 PM
Sale Price

$10.08

1 left at this price

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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 18-4546 Insert Cup is a precision-engineered water pump replacement component designed for marine outboard engines. The insert cup forms the inner liner of the water pump housing, providing a sealed chamber that directs impeller rotation and maintains proper coolant flow through the engine's cooling system.

Key Features:

  • Engineered to meet or exceed original equipment manufacturer (OEM) specifications
  • Constructed from durable materials suited to withstand the demanding marine environment
  • Direct-fit replacement for a precise, leak-free installation
  • Part of Sierra's extensive line of marine water pump components
  • Backed by Sierra's limited lifetime warranty against defects in workmanship and materials

Sierra is a trusted supplier to OEM engine manufacturers and boat builders worldwide. Sierra 18-4546 is a quality aftermarket replacement that installs with confidence during water pump rebuilds or routine cooling system maintenance.

makes spending money quick and easy

Great price and no difficulties paying. I also love getting coupons emailed to me!! Thank you!

hopefully its in stock

Great store

good

so far all good.

The estimated shipping charge to 84087 was 12.00 but at checkout it was raised 7.00 to 19.00 Checked the heater control valve, Motorcraft YG133 before installation and found that the valve does not close all the way off. This will allow hot water to circulate through the heater core and cause hot air to be blown into the passenger compartment all the time. The valve is defective or poorly manufactured. Tried to save a little money but item does not work and has cost me a weeks down time already.

Great Prices and Very Fast Shipping. Will order again in the future. Customer Service was great when I called about a question with my order.

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