单项选择题
In an engine with air inlet valve and exhaust valve on its cylinder heads the fresh air will enter into the cylinder （） and the gases exhaust （）, there being an adequate overlap between the inlet opening and the exhaust closing.
A.downwards；upwards
B.upwards；downwards
C.downwards；downwards
D.upwards；upwards
点击查看答案&解析
相关考题
-
单项选择题
In an engine with a pot-shaped piston, some lubricating oil from the main bearing will pass along a （） in the crankshaft to the bottom end bearing andthen up a connection rod to the gudgeon pin.
A.telescopic pipes
B.large bore
C.drilled passage
D.tied rod -
单项选择题
In an engine with a pot-shaped piston, some lubricating oil from the main bearing will pass along a drilled passage in the crankshaft to the bottom end bearing and then up a connection rod to the （）.
A.crosshead
B.crankpin
C.crank journal
D.gudgeon pin -
单项选择题
In addition to lubricating, cylinder oil assists in forming a gas seal and contains （） which clean the cylinder liner.
A.additives
B.water
C.grease
D.acid solution
