单项选择题
A.starting the engine hot
B.knurling the piston skirt
C.operating an overheated engine
D.using scuff resistant piston rings
单项选择题 When comparing different fuels for different engines, the ignition quality of diesel fuel oils becomes a less critical consideration as （）
单项选择题 To reduce the weight of the reciprocating parts, pistons of high-speed engines are made considerably shorterThis results in （）
单项选择题 Which of the following statements concerning cylinder liner wear is true?（）