单项选择题
A.fuel oil pressure
B.a cam operated follower
C.a spring-loaded pressure plate
D.timing gears keyed to the crankshaft
单项选择题 The total starting air capacity required for reversible main engines is to be sufficient for at least （）.
单项选择题 A large, low-speed, main propulsion diesel engine uses sea water to directly cool the （）.
单项选择题 Lube oil pumps taking suction from the sump of most small marine engines are usually （）.