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单选题
If the engine does not start on air, it may be due to （）
A
low compression of the fuel pumps
B
incorrect timing of fuel pumps
C
the starting air valves stuck
D
air-locks in fuel oil pipeline
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If the engine does not start on air, it may be due toA.low compression of the fuel pumpsB.incorrect timing of fuel pumpsC.the starting air valves stuckD.air-locks in fuel oil pipeline
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单选题If the engine does not start on air, it may be due to （）A
low compression of the fuel pumpsB
incorrect timing of fuel pumpsC
the starting air valves stuckD
air-locks in fuel oil pipeline
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failure of the fuel pumpsB
starting air pressure too lowC
stop valve in air line closedD
the turning gear still engaged
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单选题The timing of diesel engine air starting valves is controlled by（）A
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