单项选择题
A.provide exhaust back pressure
B.prevent exhaust smoke emissions
C.power a reciprocating supercharger
D.muffle exhaust gas noise
单项选择题 Which of the conditions listed could cause the cylinder relief valves on a large, low-speed, propulsion diesel engine to lift?（）
单项选择题 If you were inspecting the valve springs on an auxiliary diesel engine, your best indication of impending spring failure would be （）
单项选择题 Which of the routine maintenance procedure listed is required for starting air receivers?（）