单项选择题
A.engine to the bed
B.rocker arm to the camshaft
C.crankshaft to the gear train
D.piston to the crankshaft
单项选择题 Fuel oil transfer systems used onboard diesel propelled vessels are required to have （）.
单项选择题 In a diesel engine lube oil system, which of the following parts should be lubricated first?（）
单项选择题 Before starting a diesel engine that has an engine driven lube oil pump, the engineer should （）.