#exhaust_valve__exhaustvalve  a valve through which burned gases from a cylinder escape into the exhaust manifold
  supertype:  valve  control consisting of a mechanical device for controlling the flow of a fluid
  part of:  exhaust_system__exhaustsystem__exhaust  system consisting of the parts of an engine through which burned gases or steam are discharged
     part of:  automobile_engine  the engine that propels an automobile
        part of:  car__auto__automobile__machine__motorcar  4-wheeled motor vehicle; usually propelled by an internal combustion engine; "he needs a car to get to work"

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