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Sierra 18-3323 Marine Water Pump Kit for Mercury/Mariner 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

18-3323
09/12/2036 10:02 AM
Sale Price

$97.41

In Stock (7)

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Usually delivered within 2 days

free shipping

FREE SHIPPING

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No Hassle Returns

No Hassle Returns

Live-in-stock inventory

Live-in-stock inventory

Fitment guaranteed

Fitment guaranteed

Product Details

The Sierra 18-3323 is a complete marine water pump kit engineered as a direct replacement for Mercury Marine OEM part number 46-73640A2. Designed for Mercury and Mariner outboard motors, this kit includes every component needed for a thorough water pump service in a single package.

Sierra manufactures premium-quality aftermarket marine parts engineered to meet or exceed OEM standards, making the 18-3323 a reliable choice for routine cooling system maintenance on applicable outboard engines.

What's Included:

  • Impeller (replaces OEM #47-89983)
  • Upper pump housing
  • Water pump base
  • Drain gasket (qty. 2)
  • Lower water pump base to face plate gasket
  • Upper face plate to body gasket
  • Water pump base gaskets
  • Drain plug
  • Plate
  • O-rings (3)

OEM Cross-References:

  • Mercury Marine: 46-73640A2
  • OMC: 509031

Regular water pump impeller replacement is essential for maintaining proper engine cooling and preventing overheating damage. The Sierra 18-3323 complete pump housing kit simplifies the service process by supplying all necessary gaskets, seals, and components in one convenient kit.

I ordered a part that did not fit, returned no hassles. I just ordered two items and hope they look great.

This item was priced very attractively and shipped promptly. It was ordered on Sunday,<br>June 10th and shipped the next day, arriving at my address on Tuesday, June 12th. A very<br>satisfacory buying experience for me.

Good!

Came back because of prices. Satisfied customer

great prices with easy searching.

The LOWEST price anywhere I could find locally and on the web. easy ordering and fast shipment, even arrived 3 days prior to what was expected.

great

I needed a few small XRP fittings for our NHRA Top Alcohol Dragster, I had called XRP and even a "pro racer discount" the price was ridiculous; couple this with their ridiculous shipping/handling charge I had to go elsewhere. I typed in the XRP part number into Google and found Autoplicity, twice as many pcs. as I was planning on ordering and with shipping it was cheaper than one fitting from XRP direct. I will be checking Autoplicity anytime I'm ordering something from this day on, everything about the transaction was smooth and simple. I just got my tracking number today and the stuff is on its' way. Thanks for making this transaction so easy and not robbing your customers on something as frivolous as "handling".<br><br>Respectfully,<br>Brandon Booher<br>NHRA TAD #34

Everything went good, order shipped out the next day. The prices were good but the shipping cost was way to high $25 dollars for 2 head gaskets and some bolts oil pan bolts.

Easy purchase, and best price for what I was looking for, and shipping discount on top of that. Thanks again!

excellant

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