EXHAUST GASKET 27-825693

Function and technical context

The exhaust gasket is the watertight seal that hermetically closes the inner cover of the exhaust manifold, preventing combustion gases from leaking into adjacent areas of the engine block. In the marine exhaust system, this component must resist constant vibrations, extreme thermal cycles and the aggressiveness of the salty environment, factors that significantly accelerate the aging of its elastomers. Its deterioration causes combustion gas leaks, progressive loss of compression in cylinders, entry of water into critical areas of the engine, and in advanced stages, internal corrosion of the manifold and cascading damage to adjacent joints.

When to replace this part?

Exhaust gaskets usually show signs of failure after 300-400 hours of operation or after one or two seasons of intensive boating, especially on boats that operate in salt water. The most obvious indicators include an abnormal exhaust smell in the engine area, visible loss of compression in specific cylinders, condensation or moisture in the crankcase, and visible erosion around the gasket line. It is recommended to replace this part preventively during winter maintenance or before long journeys, since a deteriorated gasket can quickly evolve into critical leaks when the engine reaches maximum load.

Engine Compatibility

Compatible Mercury Mariner Engines

Equivalent manufacturer part numbers