单项选择题
In a diesel engine, blow-by is a result of combustion gases leaking into the crankcase past the （）
A.wrist pin bushings B.compression rings C.cylinder liner seals D.cylinder liner sealing ring
单项选择题 A centrifuge will satisfactorily remove which of the following contaminants from fuel oil?（）
单项选择题 Diesel engine ‘blow-by’ into the crankcase is caused by excessive ring（）
单项选择题 Heavy residual fuel oils are heated prior to centrifuging to （）
