单项选择题
A.centrifugal force rotates the ball-head
B.flyweight centrifugal force is balanced by spring force
C.flyweight centrifugal force is balanced by hydraulic pressure
D.speeder spring alone actuates the fuel control rod
单项选择题 If a diesel engines exhaust temperature is abnormally high, the cause could be（）
单项选择题 The knock occurring when a cold diesel engine is started and continues while running at low speed, but stops when the engine reaches normal operating speed and temperature, is（）.
单项选择题 Failure to open the diesel engine test cocks after a long period of shutdown, prior to starting may result in （）