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Sierra 18-3121 Water Pump Impeller Plate for OMC Sterndrive/Cobra - Replaces 911703

Manufacturer

Picture for manufacturer Sierra

Part Number

18-3121
10 reviews
Sale Price

$16.87

1 left at this price

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Usually delivered within 2 days

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Fitment guaranteed

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Product Details

The Sierra 18-3121 is a marine-grade water pump impeller plate designed as a direct replacement for OMC Sterndrive and Cobra stern drive cooling systems. Built to meet or exceed original equipment specifications, this wear plate is an essential component of the water pump assembly, providing a precision sealing surface for the impeller to maintain optimal coolant flow and protect your engine from overheating.

Key Features:

  • Durable, non-corrosive marine-grade construction for long service life in harsh saltwater and freshwater environments
  • Precision fit ensures proper impeller contact and maximum water pump efficiency
  • Direct OEM replacement — replaces OMC part number 911703 and GLM part number 12760
  • Designed for use in OMC Cobra sterndrive water pump assemblies (1986–1993)
  • Sold individually; one impeller plate per package

The Sierra 18-3121 impeller plate is commonly serviced as part of a complete water pump rebuild kit. Regular inspection and replacement of the impeller plate helps prevent premature impeller wear and ensures consistent coolant circulation throughout the engine cooling system.

Great prices! Had exactly what I was looking for, for $20 less than anywhere else even with the shipping cost added in.

So far so good.

i will let you know when i receive. i like the feel of the cream but do not care for the smell.

Easy transaction

I need this for tomorrow. Thanks!

Smooth transaction. Price listed when searching on Google was not the price listed on website.

Happy so far.

No hassle ordering and fast quality shipping at a reasonable price.

Very good

Low Prices!! FAST SHIPPING! The best company in the world!

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