单项选择题
A.after TDC B.before TDC C.after BDC D.before BDC
In an ordinary diesel engine the fuel injection begins ...
单项选择题In an ordinary diesel engine the fuel injection begins （）
In an oil cooler circulated by sea water, the oil is at...
单项选择题In an oil cooler circulated by sea water, the oil is at a larger pressure, the result being that any leak in the cooler will mean a loss of （）.
A.oil B.sea water C.refrigerant D.fresh water
In a four-stroke engine the camshaft rotates at （）.A.ha...
单项选择题In a four-stroke engine the camshaft rotates at （）.
A.half the engine speed B.twice the engine speed C.the engine speed D.four times the engine speed
