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Sierra 18-3420 Water Pump Base for MercCruiser Alpha One

Manufacturer

Picture for manufacturer Sierra

Part Number

118-3420
6 reviews
Sale Price

$27.49

2 left at this price

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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 18-3420 Water Pump Base is a precision-engineered replacement component designed for MercCruiser MR and Alpha One stern drives manufactured between 1985 and 1990. This critical water pump component ensures proper cooling system operation in your marine engine.

Key Features:

  • Direct replacement for MercCruiser/Mercury OEM part numbers 46-44292T1, 46-44292Q03, and 46-44292A3
  • Engineered to meet or exceed original equipment specifications
  • Compatible with gear cases featuring no pre-load pin on drive shaft and retainer under lower water pump base
  • Interchangeable with GLM 12320 and Mallory 9-43308
  • Precision manufactured for proper fit and long-lasting performance

Sierra marine parts are manufactured to OEM standards, ensuring reliable performance and durability in demanding marine environments. This water pump base is commonly included in complete water pump rebuild kits and can be purchased separately for individual component replacement.

Legit.....no problems

Great price

It was a good price on the pump I bought, but the picture showed it came complete with the nozzle assembly, but it did not so the picture is misleading

Best price, easy ordering, fast shipping, what else could you ask for?

GREAT NO PROBLEMS!!!!

Very easy, product description great

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