单项选择题
Lubricating oil is supplied to the crank-pin bearings in a marine diesel engine by （）.
A.internal crankshaft passages B.immersion in oil C.splash lubrication D.injection lubrication
单项选择题 What function is provided by the crankcase ventilation system on some diesel engines?（）
单项选择题 Increasing the valve clearance between a valve stem and rocker arm, will result in the valve （）
单项选择题 A diesel engine crankcase ventilation system （）
