A. piston crown B. piston ring groove C. piston skirt D. piston ring area
A. increased starting difficulty in cold weather B. increased oil consumption C. thickening at higher operating temperatures D. minimal friction losses
American Petroleum B. viscosity index number C. Seconds Saybolt Furol number D. Seconds Saybolt Universal number
A. reduce friction between moving surfaces B. provide even distribution of bearing wear C. reduce the accumulation of harmful detergents D. maintain a constant oil temperature output at each bearing
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