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Sierra 18-0988 Powerhead to Plate Base Gasket for Mercury Marine Outboards

Part of: Sierra Powerhead Base Gasket for Mercury/Mariner Outboard Engines

Other options in this family: Sierra 18-0319 Sierra 18-0813 Sierra 118-0319 Sierra 18-0643 Sierra 118-0103

Manufacturer

Picture for manufacturer Sierra

Part Number

18-0988
13 reviews
Sale Price

$12.07

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 18-0988 is a precision-cut Powerhead to Plate Base Gasket designed as a direct replacement for Mercury Marine outboard engines. This individual gasket seals the critical interface between the powerhead (engine block assembly) and the mid-section mounting plate, preventing exhaust and water intrusion at one of the most stress-exposed sealing points on a two-stroke outboard motor.

Key Features:

  • Direct replacement for Mercury Marine OEM part numbers 27-62860, 27-628601, and 27-37976
  • Also interchangeable with GLM 31640 and Mallory 9-60058
  • Meets or exceeds original equipment specifications for fit, form, and function
  • Manufactured to Sierra International's marine-grade quality standards
  • Sold as a single gasket — quantity 1

Sierra International is a trusted name in marine replacement parts, and each Sierra gasket meets or exceeds the original equipment part it replaces. Whether performing a powerhead rebuild or addressing a base seal failure, the 18-0988 delivers a reliable, leak-free seal. Always verify fitment by cross-referencing the OEM part number from your engine's parts diagram before ordering.

Quick an easy checkout

Quick and easy

Quick and reasonable!

Excellent pricing

Awesome

Great place to buy automotive stuff. Good customer service and has good automotive products.

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Great so far.

I was planning on ordering a race suit, had lot of questions. The support staff were extremely knowledgeable, courteous and had answers for all my questions. Placed the order online and product shipped the next day. Very happy with the customer service and the whole shopping process in general. Nice shopping experience

So far so good

VERY GOOD

Autoplicity had the best price for what I needed. I received my order within 2 days boxed up nice and tight. What more could you ask for? I will be a repeat customer.

Great product. Fast shipping. Great seller. Thanks again.

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