单选题The camshaft on a four-stroke/cycle diesel engine provides a means to operate the （）.Afuel injectorsBexhaust valvesCintake valvesDall of the above
单选题
The camshaft on a four-stroke/cycle diesel engine provides a means to operate the （）.
A
fuel injectors
B
exhaust valves
C
intake valves
D
all of the above
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相关考题：
Proper lubrication of the main bearings is more easily obtained in a single acting, four-stroke/cycle diesel engine than in a tow-stroke/cycle diesel engine because________.A.The direction of pressure on the journal in four-stroke engine is continuouslyB.positive feed lubricators are installed on all bearings of four-stroke engine, whereas as a splash feed system is used on tow-stroke engineC.four-stroke engines usually utilize a heavier grade of oil than tow-stroke enginesD.Low-stroke engines usually consume less lube oil than four-stroke engines
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单选题The reversing cams of some four-stroke/cycle diesel engines are brought into position by （）Asliding the camshaft along its axisBrotating the cam 180Crotating the cam followers 180Dmoving the idler sprockets in the drive chain
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