Sierra Carb Bowl Gasket 18-2575-9, Replaces Mercury 1399-99, Pack of 2

The Sierra 18-2575-9 Carb Bowl Gasket is a round carburetor bowl gasket sold in a package of 2, designed as a direct replacement for Mercury marine part 1399-99. This gasket seals the carburetor bowl to the carburetor body, preventing fuel leaks and maintaining proper air-fuel mixture at the seal surface. Because carburetor bowl gaskets compress and lose their seal over time from heat cycling and fuel exposure, they are a routine wear item that should be replaced whenever the carburetor bowl is removed for cleaning, float adjustment, or jet service.

Each package contains 2 gaskets, so a spare is on hand for the next service interval or for outboards with more than one carburetor. The round shape and dimensions are matched to the Mercury outboard carburetor bowls used with part 1399-99, so installation is a straightforward bowl-off, gasket-swap, bowl-on job with no modification required. Sierra manufactures this gasket to be a fit-for-fit and function-for-function match to the original equipment part it replaces.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-2575-9
• Product Type: Carburetor Bowl Gasket
• Package Quantity: 2 gaskets per package
• Shape: Round
• Weight: 0.01 pounds
• UPC: 808282163099

Fitment

• Mercury marine outboard carburetors originally equipped with part number 1399-99

Replaces (OEM)

• 1399-99

Frequently Asked Questions

What does the Sierra 18-2575-9 carb bowl gasket fit? The Sierra 18-2575-9 is a direct replacement for Mercury marine carburetor bowl gasket 1399-99, sealing the carburetor bowl to the carburetor body on the Mercury outboards that originally used that part.

How many gaskets come in a package of 18-2575-9? Each package of the 18-2575-9 carb bowl gasket contains 2 gaskets, which covers a single carburetor service with a spare for the next one or a second carburetor.

What shape is the 18-2575-9 carb bowl gasket? The 18-2575-9 gasket is round, matching the mounting flange of the carburetor bowl it seals on Mercury outboard applications using original part 1399-99.

Does 1399-99 cross-reference to the Sierra 18-2575-9? Yes, Sierra part 18-2575-9 is manufactured to replace Mercury marine part number 1399-99 and installs in the same location.

How much does the 18-2575-9 carb bowl gasket weigh? The Sierra 18-2575-9 carb bowl gasket weighs 0.01 pounds per package of 2.

When should I replace the carburetor bowl gasket on my Mercury outboard? Replace the 18-2575-9 carb bowl gasket any time the carburetor bowl is removed for cleaning, float service, or jet replacement, since the compressed gasket rarely reseals reliably once disturbed.

Is the Sierra 18-2575-9 gasket genuine Mercury or aftermarket? The 18-2575-9 is a Sierra-manufactured aftermarket gasket built to replace Mercury part 1399-99, not a Mercury-branded original equipment part.

What is included when I order the 18-2575-9? Ordering the Sierra 18-2575-9 gets you one package containing 2 round carburetor bowl gaskets; no other hardware is included.

Can I install the 18-2575-9 carb bowl gasket myself? Installation is straightforward: remove the carburetor bowl, remove the old gasket, seat the new 18-2575-9 gasket, and reinstall the bowl, making it a job most owners can do without special tools.

Is the Sierra 18-2575-9 gasket reusable after removal? No, carburetor bowl gaskets like the 18-2575-9 are designed for one-time use and should be replaced with a fresh gasket from the package each time the bowl is removed.