Sierra 18-0488 Intake Gasket, Replaces Mercury Marine 27-807473A1

The Sierra 18-0488 is a white intake gasket engineered as a direct equivalent for Mercury Marine engines that call for OEM number 27-807473A1. It seats between the intake manifold and engine block to seal against exhaust gas and coolant leakage at the intake mating surface, a common failure point as factory gaskets age and lose compression. The gasket is round in shape and manufactured to OEM specifications for fit and sealing performance, making it a straightforward like-for-like replacement during a manifold gasket job or general engine maintenance. At 0.33 pounds, it ships as a single-count gasket ready to install without modification. Because it is built to OEM dimensions and material specification, it installs the same way the original Mercury Marine gasket does, using the same fastener pattern and sealing surface, so no special tools or adapters are required beyond a standard gasket replacement procedure.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-0488
• Product Type: Intake Gasket
• Color: White
• Shape: Round
• Country of Origin: Taiwan
• Weight: 0.33 pounds
• UPC: 808282187255

Fitment

Designed for Mercury Marine engines originally fitted with intake gasket 27-807473A1.

Replaces (OEM)

• 27-807473A1

Frequently Asked Questions

What does the Sierra 18-0488 intake gasket fit? The Sierra 18-0488 is built as a direct equivalent for Mercury Marine intake applications that originally used OEM gasket 27-807473A1.

Is Sierra 18-0488 the same as Mercury Marine 27-807473A1? Yes, part number 18-0488 is manufactured to replace Mercury Marine OEM gasket 27-807473A1 directly, matching its fit and sealing function.

What color is this gasket? The 18-0488 intake gasket is white.

What shape is the Sierra 18-0488 gasket? It is round in shape, matching the sealing surface it is designed to cover.

How much does the 18-0488 intake gasket weigh? This gasket weighs 0.33 pounds.

Where is the Sierra 18-0488 gasket manufactured? The country of origin for the 18-0488 intake gasket is Taiwan.

Is this a genuine Mercury Marine part or an aftermarket replacement? The 18-0488 is a Sierra-branded aftermarket gasket engineered to OEM specifications as a replacement for Mercury Marine 27-807473A1, not a genuine Mercury Marine part.

How many gaskets come in the package? The Sierra 18-0488 is sold as a single gasket, one unit per package.

Can I install the 18-0488 gasket myself? Yes, since it matches the OEM fit and dimensions of 27-807473A1, it installs the same way as the original Mercury Marine gasket during a standard intake manifold service.

What is the UPC for the Sierra 18-0488 intake gasket? The UPC for the 18-0488 intake gasket is 808282187255.