Sierra 18-0487 Intake Manifold Gasket for Mercury 4.3L and MCM 262 Mag Engines, Replaces 27-8243261

The Sierra 18-0487 is an intake manifold gasket built to seal the connection between the intake manifold and cylinder heads on select Mercury marine engines, preventing air, fuel, and coolant leaks at that joint. It is a direct replacement for Mercury gasket 27-8243261, giving boat owners and technicians a way to source the correct seal without going through Mercury directly. The gasket is engineered to match the original fit for the MCM 262 Mag and 4.3L/LX/LH/LXH (Gen+) engine family, 1996 and later, so it lines up with the factory mounting points and sealing surfaces without modification.

Each package contains one gasket (Sierra part number 18-0487), identified by UPC 808282187248. As a wear item, the intake manifold gasket is typically replaced whenever the intake manifold is removed for service, or when a leak develops at the intake-to-head joint. Installing the correct gasket helps maintain proper sealing and engine performance on the engines it is designed for.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-0487
• Product Type: Intake Manifold Gasket
• UPC: 808282187248
• Number of Items: 1
• Weight: 0.35 pounds
• Replaces (OEM): 27-8243261

Fitment

• MCM 262 Mag and 4.3L/LX/LH/LXH (Gen+) engines, 1996 and later

Replaces (OEM)

• 27-8243261

Frequently Asked Questions

What engines does the Sierra 18-0487 intake manifold gasket fit? The Sierra 18-0487 fits the MCM 262 Mag and 4.3L/LX/LH/LXH (Gen+) Mercury engine family, 1996 and later.

Is the Sierra 18-0487 a cross-reference for Mercury gasket 27-8243261? Yes, the 18-0487 is a direct replacement for Mercury intake manifold gasket 27-8243261.

How many gaskets are included with the Sierra 18-0487? One intake manifold gasket is included per package of the Sierra 18-0487.

How much does the Sierra 18-0487 gasket weigh? The Sierra 18-0487 intake manifold gasket weighs 0.35 pounds.

What is the UPC for the Sierra 18-0487 intake manifold gasket? The UPC for the Sierra 18-0487 is 808282187248.

Does the 18-0487 fit 4.3L LX and LH engine variants? Yes, the 18-0487 is designed for the 4.3L/LX/LH/LXH (Gen+) engines in addition to the MCM 262 Mag.

When would I need to replace this intake manifold gasket? Replacement of the 18-0487 is typically needed when the intake manifold is removed for service or when a leak develops at the intake-to-head sealing surface on a fitted MCM 262 Mag or 4.3L/LX/LH/LXH (Gen+) engine.

What Sierra part number should I order for this Mercury gasket? Order Sierra part number 18-0487, which replaces Mercury gasket 27-8243261.

Is the Sierra 18-0487 an OEM Mercury part or an aftermarket equivalent? The 18-0487 is a Sierra-brand gasket manufactured as a replacement for Mercury gasket 27-8243261, not an OEM Mercury part.

What model year range does the 18-0487 gasket cover? The 18-0487 is listed for MCM 262 Mag and 4.3L/LX/LH/LXH (Gen+) engines built in 1996 or later.