AIB2C Exhaust Elbow Gasket Set for Mercruiser — 4‑Piece Direct‑Fit Composite Seal

AIB2C Exhaust Elbow Gasket 18-2849-1 (fits Mercruiser 27-818832, 27-863726) is a four-piece aftermarket gasket set engineered to restore a tight, OEM-pattern seal between exhaust elbow and manifold on compatible Mercruiser stern drives.

When your stern drive shows signs of exhaust or coolant leakage near the elbow/manifold joint, replacing the gasket with correctly sized, durable parts is a simple maintenance step that prevents corrosion and performance loss. This AIB2C set contains four gaskets made from high-quality material that match original hole and port patterns for a direct fit. It replaces several OEM and aftermarket references so installers can swap them in without modifying mating surfaces.

How does this gasket fit my Mercruiser stern drive?

The AIB2C gasket set is manufactured to replicate OEM hole spacing and port contours so it aligns with exhaust elbow flanges on many Mercruiser models. That ensures bolt holes register cleanly and the exhaust/coolant passageways remain unobstructed.

• Direct-fit replacement for Mercruiser part numbers including 27-863726 and 27-818832
• Replaces Mallory 9-61414, GLM 32080, Osco 8503-GO for cross-compatibility
• Four pieces included for multi-port or twin exhaust setups

What materials and durability can I expect?

These gaskets are produced from a resilient, heat- and corrosion-resistant composite designed for marine exhaust conditions. They provide a reliable seal under temperature cycling and exposure to saltwater environments when installed correctly.

• High-quality composite construction resists compression set and deterioration
• Designed for repeated thermal expansion and contraction
• Corrosion-resistant to prolong manifold and elbow life

How do I install the AIB2C Exhaust Elbow Gasket set?

Installation is straightforward for anyone comfortable with basic marine engine work: remove the old gasket, clean mating surfaces thoroughly, position the new gasket so bolt holes align, then torque bolts to manufacturer specs. Use recommended sealants only if specified by your engine manual.

• Remove old gasket and clean surfaces to bare metal or factory finish
• Align gasket with bolt holes and exhaust/coolant ports before tightening
• Tighten bolts in a crisscross pattern to the engine maker’s torque settings

Which engines and part numbers does this replace or match?

This four-piece set is intended to match a range of Mercruiser exhaust elbow/manifold configurations and cross-references multiple OEM and aftermarket part numbers. Confirm compatibility with your engine model and serial number before purchasing.

• Replaces Mercruiser: 27-863726, 27-818832, 27-860232, 27-871051, 27-87105
• Also replaces Mallory 9-61414, GLM 32080, Osco 8503-GO
• Sold as a 4-piece pack to service multiple joints or spare parts

Who is this for: Boat owners, marine mechanics, and DIY enthusiasts needing a dependable, OEM-pattern gasket set for Mercruiser stern drive exhaust elbows will find this AIB2C kit useful. It’s aimed at anyone undertaking routine engine maintenance, repairing exhaust leaks, or replacing worn gaskets without custom machining. Verify part numbers and engine compatibility before installing, and follow your engine manufacturer’s torque and sealant recommendations for best results.