单项选择题
A.Liner wear is distributed equally between the upper and lower portions of the cylinder
B.Excessive liner wear causes wear between piston ring and groove
C.Excessive, but uniform liner wear will not cause wear between piston ring and groove
D.Liner wear is normally greatest in the middle of the cylinder
单项选择题 If clearance between a piston and the cylinder wall is excessive, piston slap will occurThe slap itself is caused by （）
单项选择题 Poor quality fuel being used in a turbocharged medium-speed, diesel engine could result in （）
单项选择题 Many diesel engine exhaust valves are being constructed with hollow stems filled with sodium in order to （）