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单选题
A hot air start pipe indicates that there is （）.
A
inefficient cooling
B
a leaking air start valve
C
a clogged drain valve
D
a leaking air bottle
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oil sumpB
oil separatorC
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单选题Diesel engine air start valve timing is controlled by（）A
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单选题（） is usually driven by the engine camshaft and supplies pilot air to the cylinder air start valve.A
An air receiverB
An operating valveC
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单选题If the engine does start on air, but combustion does not immediately begin, the cause may be （）.A
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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air chamberB
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单选题（） supplies pilot air to control the cylinder air start valves.A
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fouled turbochargerC
bad combustionD
excessive air
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less moisture than cold airB
more moisture than cold airC
the same amount of moisture as cold airD
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单选题A dazzling white burner flame in the boiler furnace indicates （）.A
no combustionB
deposits in the fuelC
excessive air in the fuelD
cold fuel oil
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