单项选择题
The jacket water temperature in a diesel engine closed freshwater cooling system is normally controlled by （）
A.regulating the level of corrosion inhibitor in the primary cooling system B.the level of the freshwater expansion tank C.varying the engine load to meet temperature requirements D.the operation of the thermostatic valve
单项选择题 For diesel engine piston cooling, lubricating oil can be supplied to the pistons by a/an （）.
单项选择题 In a four-stroke/cycle diesel engine, the camshaft rotates at （）
单项选择题 A restricted air intake to a diesel engine may result in the engine （）.
