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Sierra 18-0643 Powerhead Base Gasket for Mercury/Mariner Outboard Engines

Manufacturer

Picture for manufacturer Sierra

Part Number

18-0643
13 reviews
Sale Price

$20.88

In Stock (8)

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Usually delivered within 2 days

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Fitment guaranteed

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Product Details

The Sierra 18-0643 Powerhead Base Gasket is a precision-engineered replacement gasket designed for Mercury and Mariner V6 outboard engines. This gasket seals the critical interface between the powerhead assembly and the adapter/base, preventing exhaust leaks and maintaining proper compression during engine operation.

Manufactured by Sierra International to meet or exceed OEM specifications, this gasket offers a reliable, cost-effective alternative to the original Mercury Marine part. It is constructed from durable marine-grade materials engineered to withstand the high heat, pressure, and corrosive environment of two-stroke outboard powerhead applications.

Key Features:

  • Direct OEM replacement for Mercury/Mariner outboard engines
  • Designed for Mercury/Mariner 2.0L and 2.5L V6 outboard applications
  • Meets or exceeds original equipment specifications
  • Marine-grade materials for durability in high-heat, high-pressure environments
  • Sold individually as a single gasket

OEM Cross-Reference Part Numbers:

  • Mercury Marine: 27-18307 6, 27-18307-1, 27-183071, 27-183076
  • Also cross-references: 37570, 510-36, 2714

The Sierra 18-0643 powerhead base gasket is also included as a component in Sierra's complete powerhead gasket sets, making it easy to source as a standalone replacement when only this individual gasket is needed during engine service or rebuild.

very smooth

Found what I needed quickly

This is the first time I ordered from Autoplicity. Very good experience overall. The prices are the best I can find anywhere online. It was shipped very quickly, and I received my item just in time before my trip. Thanks!

BEST PRICE AVAILABLE! QUICK SHIPPING.

Grate

Fast and Simple, great prices!!

I have place my order on line and I am very satisfied with your services , I wil recommend every one to purchase from you

great

Absolutely the best bargain you'll find! Don't pay retail mark up at the parts store, buy at Autoplicity and know you're saving money.<br>.

easy and fast ordering

So far so good.

Best price with shipping from any auto supply house ! Fast shipping with tracking number emailed right away ! This is my new parts house !

I ordered this product and Wednesday in the morning and it was on my door step Thursday morning with regular shipping. The ordering process was super easy and the price was $35 cheaper than any other online retailer. The Rack is awesome, easy to assemble took me about 20 minutes by myself, put on my jeep hooked up the bikes and off I went, fantastic design, I highly recommend the Rola NV2 bike rack and highly recommend Autoplicity

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