单项选择题
On a four-stroke diesel engine, when the piston is driven downwards by the expanding gas, it delivers power to the crankshaft through the （）.
A.thrust block B.sounding rod C.connecting rod D.push rod
单项选择题 On a diesel engine, fuel is delivered into the combustion space by （）.
单项选择题 Oil will lubricate these parts （） effectively than water.
单项选择题 Oil pressure in the lubrication system is （） the static sea water head to ensure that sea water （） the stem-tube.
