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Sierra 18-99140 Cylinder Head Gasket for Yamaha 9.9HP 13.5HP 15HP 2-Stroke Outboard

Manufacturer

Picture for manufacturer Sierra

Part Number

18-99140
10 reviews
Sale Price

$26.69

1 left at this price

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Usually delivered within 2 days

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Product Details

The Sierra 18-99140 is a cylinder head gasket engineered as a direct replacement for Yamaha 2-stroke outboard motors. It directly replaces Yamaha OEM part numbers 63V-11181-A1-00 and 63V-11181-A2-00, providing a precise-fit seal between the cylinder head and engine block.

Manufactured by Sierra International, a trusted name in marine replacement parts, this head gasket is built to meet or exceed the original equipment specifications it replaces. Sierra products are engineered to stand up in the demanding marine environment, ensuring reliable sealing performance and long service life.

Key Features:

  • Direct replacement for Yamaha cylinder head gasket
  • Replaces Yamaha OEM part numbers: 63V-11181-A1-00 and 63V-11181-A2-00
  • Also cross-references Mallory part number 9-63955
  • Designed for Yamaha 2-stroke outboard engines: 9.9HP, 13.5HP, and 15HP
  • Meets or exceeds original equipment standards
  • Built to withstand the harsh marine environment

OEM / Cross-Reference Part Numbers:

  • Sierra: 18-99140
  • Yamaha: 63V-11181-A1-00, 63V-11181-A2-00, 63V-11181-A0, 63V-11181-00
  • Mallory: 9-63955

This gasket is an essential component during powerhead rebuilds, overhauls, or any repair requiring cylinder head removal on compatible Yamaha 2-stroke outboard engines.

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