单项选择题
A.brought about B.caused for C.resulted from D.led
The lube oil to lubricate the surfaces of the cylinder ...
单项选择题The lube oil to lubricate the surfaces of the cylinder liners is spread over by the （）.
A.sliding piston rings B.engines camshaft C.small pumps D.forced feed system
The most important factor that causes the wear of the e...
单项选择题The most important factor that causes the wear of the engine parts is （）.
A.excessive heat B.friction C.oxidation D.high pressure
In the closed cooling system, the water （）.A.is made to...
单项选择题In the closed cooling system, the water （）.
A.is made to circulate out of the system B.is made to circulate within the system C.is made circulate within the system D.is made circulate out of the system
