Generally the function of lubrication is to form of a film of lubricant between any two surfaces that have relative （）, so that surfaces dont get touch with each other.

Fuels of high quality with their earlier ignitions will...

单项选择题Fuels of high quality with their earlier ignitions will cause higher （）pressure in cylinders of a diesel engine.

Fuel pump index is （）.A.the viscosity indexB.the fuel o...

单项选择题Fuel pump index is （）.

Fuel oil is thought to be one of the main factors （） th...

单项选择题Fuel oil is thought to be one of the main factors （） the operation and maintenance of an engine.