Marine Exhaust Mufflers

The muffler design used on a boat is dictated by many parameters, including whether the engine is located above or below the waterline, its power output and the resulting exhaust system diameter, and the level of noise reduction. Above-waterline applications use inline mufflers, which look much like those installed in cars. A more typical motor location is below the waterline, which requires a waterlift type of muffler. It is basically a canister with a side inlet pipe and top outlet pipe. The pressure pushes the gases and cooling water up the exhaust piping, which then loops above the waterline and has an anti-siphon valve at the top of the loop to prevent water from flowing back into the exhaust, filling the muffler and exhaust manifolds, and eventually flooding the engine.

Marine mufflers are typically made from stainless steel, fire-retardant fiberglass, or plastic. Steel models may fail due to corrosion; those constructed of plastic or fiberglass may get damaged due to overheating caused by the interrupted flow of cooling raw water. The silencer that has developed a leak should be replaced. We have replacement mufflers for a variety of applications, available in different designs and materials. And if you’re looking for a silencer designed to keep the sound levels down and horsepower up, we’ve got you covered.