Sierra 18-4389 Intake Manifold Gasket Set, Replaces 27-11977A88, for GM 262 CID 4.3L 175-205 HP Marine Engines

The Sierra 18-4389 Intake Manifold Gasket Set seals the intake manifold on GM 262 CID (4.3L) marine engines rated 175, 185, and 205 HP. It is designed as a direct replacement for the factory gaskets on this engine family, restoring a proper seal between the intake manifold and cylinder heads to prevent vacuum leaks, coolant intrusion, and oil seepage that can develop as the original gaskets age and harden.

This set includes the 18-3879 head gasket, so installers have the additional gasket needed for a complete intake-area reseal without having to source it separately. It cross-references directly to Mercury Marine part numbers 27-11977A88 and A92, making it easy to confirm this is the correct replacement when servicing GM 262 CID / 4.3L marine engines within the specified horsepower range.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-4389
• Category: Mercruiser Engine Gasket Sets
• Weight: 1.32 pounds
• UPC: 030999563521
• Includes: 18-3879 Head Gasket
• Engine Fitment: GM 262 CID Eng; 175, 185 & 205 HP, 4.3L
• OEM Cross Reference: 27-11977A88, A92

Fitment

• GM 262 CID Engine, 4.3L
• 175, 185 & 205 HP

Replaces (OEM)

• 27-11977A88
• A92

Frequently Asked Questions

What engine does the Sierra 18-4389 fit? The Sierra 18-4389 Intake Manifold Gasket Set fits GM 262 CID (4.3L) marine engines rated 175, 185, and 205 HP.

What OEM part numbers does 18-4389 replace? It replaces Mercury Marine part numbers 27-11977A88 and A92, so it is a direct match for engines originally fitted with either of those gaskets.

Does this set include a head gasket? Yes, the 18-4389 set includes the 18-3879 head gasket in addition to the intake manifold gasket components.

How much does the 18-4389 gasket set weigh? This Sierra intake manifold gasket set weighs 1.32 pounds.

Is the Sierra 18-4389 an OEM or aftermarket part? It is a Sierra aftermarket gasket set manufactured to match the fit of Mercury OEM numbers 27-11977A88 and A92 for GM 262 CID 4.3L marine engines.

Will 18-4389 work on a 4.3L GM marine engine rated 220 HP? The Sierra 18-4389 is specified for GM 262 CID 4.3L engines rated 175, 185, and 205 HP; horsepower ratings outside that range are not covered by this listing.

What is included in the box with part 18-4389? The box contains the intake manifold gasket set along with the 18-3879 head gasket for this GM 262 CID 4.3L application.

Can I use the UPC to verify I am ordering the correct gasket set? Yes, Sierra 18-4389 carries UPC 030999563521, which can be used to confirm the exact product when ordering.

What material is the 18-4389 gasket set made from? The dossier for this listing does not specify the gasket material for the Sierra 18-4389 set.

Does the 18-4389 gasket set fit inline 6-cylinder GM engines? No, the 18-4389 is specified for the GM 262 CID (4.3L) V-type engine family rated 175, 185, and 205 HP, not inline 6-cylinder applications.

How do I know this gasket set matches my Mercury-powered boat? If your engine's original gasket carries Mercury number 27-11977A88 or A92, the Sierra 18-4389 is the matching replacement set.