Sierra 18-0887 Timing Cover Gasket for GM 4.3L, 5.0L & 5.7L Engines, Replaces 3852654, 3853512

The Sierra 18-0887 Timing Cover Gasket seals the timing cover against the engine block on GM 4.3L, 5.0L, and 5.7L marine engines, preventing oil leaks at this critical junction. It is a direct-fit replacement gasket designed to restore a proper seal when the original gasket has hardened, cracked, or begun leaking from age and heat cycling. Installing a fresh timing cover gasket during a timing cover removal, timing chain service, or general engine reseal helps ensure the cover seats correctly and holds oil pressure without seepage.

This gasket is manufactured to match the mounting pattern and sealing surface of the OEM GM timing cover gasket, cross-referencing directly to OEM part numbers 3852654 and 3853512. Because it is a precise fit replacement, no modification to the timing cover or engine block is required during installation. Boat owners and marine mechanics use it as a maintenance part whenever the timing cover is removed for inspection, repair, or replacement of related timing components.

Specifications

• Brand: Sierra
• Manufacturer Part Number: 18-0887
• Product Type: Timing Cover Gasket
• Engine Compatibility: GM 4.3L, 5.0L & 5.7L
• OEM Cross-Reference: 3852654, 3853512
• Weight: 0.07 pounds

Fitment

• GM 4.3L engines
• GM 5.0L engines
• GM 5.7L engines

Replaces (OEM)

• 3852654
• 3853512

Frequently Asked Questions

What engines does the Sierra 18-0887 timing cover gasket fit? The Sierra 18-0887 timing cover gasket fits GM 4.3L, 5.0L, and 5.7L marine engines.

What OEM part numbers does this gasket replace? Sierra 18-0887 replaces OEM GM part numbers 3852654 and 3853512.

Is 18-0887 a direct OEM replacement? Yes, the Sierra 18-0887 is a direct cross-reference replacement for OEM timing cover gaskets 3852654 and 3853512, so no modification is needed for installation on compatible GM engines.

How much does the timing cover gasket weigh? The Sierra 18-0887 timing cover gasket weighs 0.07 pounds.

When should this gasket be replaced? This gasket should be replaced any time the timing cover is removed from a GM 4.3L, 5.0L, or 5.7L marine engine, such as during timing chain service or if the original gasket is leaking oil.

Can this gasket be reused after removing the timing cover? No, a timing cover gasket like the Sierra 18-0887 should be replaced with a new one any time the timing cover is removed, since reusing a compressed gasket can result in oil leaks.

Does the Sierra 18-0887 fit both carbureted and fuel-injected GM 4.3L, 5.0L, and 5.7L engines? The Sierra 18-0887 is listed as fitting GM 4.3L, 5.0L, and 5.7L engines generally, based on displacement rather than fuel delivery type.

What brand is part number 18-0887? Part number 18-0887 is manufactured by Sierra.

Will this gasket seal correctly without additional sealant? The Sierra 18-0887 is designed to match the OEM sealing surface and pattern of gaskets 3852654 and 3853512 for proper sealing when installed per standard timing cover installation procedures.

Is the Sierra 18-0887 gasket sold individually? The Sierra 18-0887 timing cover gasket is a single gasket part matched to GM 4.3L, 5.0L, and 5.7L timing covers.