An exhaust valve assembly has a valve actuator, a first valve part (FVP) operatively connected to the actuator, a second valve part (SVP), and at least one auxiliary valve operatively connected to the second valve part. When the actuator is in a first position, the FVP is in a fourth position, the SVP is in a seventh position and the at least one auxiliary valve is in a ninth position. When the actuator is in a second position, the FVP is in a fifth position, the SVP is in the seventh position and the at least one auxiliary valve is in the ninth position. When the actuator is in a third position, the FVP is in a sixth position, the SVP is in an eighth position and the at least one auxiliary valve is in a tenth position. The second position is intermediate the first and third positions.