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Sierra 18-3321 Marine Water Pump Kit for MerCruiser Stern Drive

Manufacturer

Picture for manufacturer Sierra

Part Number

18-3321
12 reviews
Sale Price

$101.31

In Stock (9)

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Usually delivered within 2 days

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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 18-3321 is a complete marine water pump repair kit designed as a direct replacement for MerCruiser stern drive cooling systems. This comprehensive kit includes all the components needed to fully restore raw water pump function, eliminating the time and effort of sourcing individual parts separately.

Kit Includes:

  • Water pump base (replaces Mercury OEM 46-96146A6)
  • Water pump housing (46-96148A1)
  • Impeller (47-89984)
  • Impeller plate
  • Water tube guide/grommet
  • Water pump base-to-gear housing gaskets
  • Lower and upper wear plate gaskets
  • Gear housing drain screw gaskets (qty. 2)
  • Seal ring
  • Multiple O-rings (assorted sizes)

OEM Cross-References:

  • Mercury / Mercruiser: 46-96146A6
  • Sierra Water Pump Base: 18-3421
  • Sierra Impeller: 18-3017
  • Sierra Housing: 18-3116

Key Features:

  • Meets or exceeds original equipment (OEM) standards
  • Engineered for high-horsepower marine engine demands
  • Constructed from high-quality rubber compounds, stainless steel, and composite plastics for durability in harsh marine environments
  • For MerCruiser #1 units with flush — serial numbers 2495186 through 2763441

Sierra International is a leading global manufacturer of aftermarket marine engine and drive parts with over 58 years of industry experience. All Sierra water pump kits are designed to circulate water for optimal engine temperature regulation, helping prevent overheating and costly engine damage.

Quick and fast!

Fast and simple process.

cool

Great price and good company to buy from!

Good SO far!

Very high level of responsive customer service, wow! And the items arrived immediately, so fast I thought there might be a mistake. :D<br>thx Sean!

Great place to shop, low prices and ease of website to browse!

clear product description. Quick checkout process.

The price was really good compared to other places I looked. They shipped my order the next day which was really nice as I needed the product ASAP. Thanks Autoplicity

I had a hard time getting to where I wanted but once there it was OK.

Easy to order

gave me a 20% off shipping code but didn't give me a place to use it

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