单项选择题
A.prevents spark generation
B.removes combustible gases
C.determines the level of combustible gases
D.provides inert gas generation in crankcase
单项选择题 Regarding a Diesel engine crankcase, the general arrangement and installation should preclude the possibility of （）
单项选择题 If the valve tappets in a diesel engine are set at greater clearances than those specified by the engine manufacturer, those valves will （）
单项选择题 Lubricating systems for diesel engines are usually designed to initially provide lube oil to the engine （）