Exhaust systems are for outboard marine engines that are configured to propel a marine vessel in a body of water. An intermediate exhaust conduit is configured to receive the exhaust gas from the primary exhaust conduit. A primary muffler receives the exhaust gas from a intermediate exhaust conduit. A secondary muffler receives the exhaust gas from the primary muffler. An idle relief outlet discharges the exhaust gas from the secondary muffler to atmosphere. A bypass valve is positionable into an open position wherein the exhaust gas is permitted to bypass the secondary muffler and flow from the primary muffler to the idle relief outlet and into a closed position wherein the exhaust gas is not permitted to bypass the secondary muffler and instead flows from the primary muffler to the idle relief outlet via the secondary muffler.
Actively tunable exhaust systems for outboard marine engines
2018-04-17
Patent
Electronic Resource
English
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