A solid exhaust seal isn’t something you think about until it starts causing trouble — but by then, it’s already too late. The Mercury Marine Exhaust Manifold Gasket - 27-46820 is designed to keep exhaust gases right where they belong, sealing the critical connection between the manifold and cylinder head on MCM and MIE GM V-8 marine engines. Built tough to handle the constant heat, pressure, and exposure to moisture that comes with life on the water, it’s a key player in keeping your exhaust system tight and your engine breathing clean.

Unlike generic gaskets that can compress unevenly or break down under stress, this Mercury OEM gasket is cut to exact specs for a precise fit. That kind of precision matters when you’re dealing with hot exhaust pulses, especially under load. The materials are heat-resistant, designed to hold their shape, and resist the kind of deterioration that comes with hours of running at higher RPMs.

Why this gasket earns its place:

• Built specifically for MCM and MIE GM V-8 marine engines — no trimming, no guesswork
• High-temperature materials handle constant heat cycling and exposure to moisture
• Precise OEM fit guarantees reliable sealing and long-term durability

Ideal scenarios for installing:

1. Replacing gaskets during exhaust manifold swaps or upgrades
2. Addressing exhaust leaks that can sap performance and put nearby components at risk
3. Routine maintenance on high-hour GM V-8 marine engines

A quality exhaust gasket might be a small piece of the puzzle, but it’s the kind of detail that keeps your engine running right — and keeps those exhaust leaks where they belong: outside the engine bay.