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单选题
The air required for combustion is taken from the engine room through a filter fitted on the turbochargerThis reduces the risk for too and contamination of the combustion air（）
A
high temperatures
B
low temperatures
C
wet
D
dirty
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clogged air intake passagesD
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单选题White smoke exhausting from an operating diesel engine may indicate （）.A
a cracked linerB
burning lube oilC
an overloaded engineD
insufficient combustion air
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单选题In a diesel engine, the time taken to heat the fuel particles, turn them into vapor, and bring about combustion is called （）A
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ignition delayC
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单选题Combustion knock can occur in the cylinders of a diesel engine under any condition permitting （）.A
a shortened ignition delay periodB
a lean fuel/air mixtureC
excess fuel in the combustion chamberD
rapid vaporization of injected fuel droplets
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单选题Poor combustion in a diesel engine can be caused by （）.A
high compression pressureB
low intake air temperatureC
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单选题The power developed by a large slow-speed main propulsion diesel engine is dependent upon the （）A
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proportion of trapped air that is utilized in the combustion processC
thermodynamic efficiency of the engine cycleD
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单选题In describing basic diesel engine operation，the term ‘event’ refers to （）A
the production of high pressure gasesB
the removal of expended combustion gasesC
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单选题The term diesel engine scavenging means（）A
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forcing the products of combustion out of the cylinder with the fresh air chargeC
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单选题If the engine does start on air, but combustion does not immediately begin, the cause may not be （）.A
low compressionB
failure of the fuel pump to discharge fuelC
incorrect timing of fuel pumpD
turning gear being still on
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单选题Gas exchange, which is a basic part of the cycle of an internal combustion engine, is（）A
the supply of normal air and removal of compressed airB
the supply of fuel oil and combustion of the atomized oilC
the supply of fresh air and removal of exhaust gasesD
the supply of fresh air and removal of the extra heat
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单选题The diesel engine is a type of internal combustion engine which ignites the fuel by injecting it into hot, high pressure air in a （）.A
air bottleB
air compressorC
crank caseD
combustion chamber
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单选题As for a diesel engine, lack of combustion air may be due to （）.A
fouling turbineB
fuel pump faultsC
lubrication failureD
excessive cooling
考题
单选题How does combustion air enter the cylinder of a two-cycle diesel engine?（）A
Cylinder head valvesB
PortsC
Turbo chargersD
Bleeder valves
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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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单选题Starting air for auxiliary engines may be taken directly from the main reservoirs or through （）.A
an auxiliary reservoirB
a controlling air bottleC
an emergency air compressorD
a main air compressor
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单选题Which of the following problems should be taken when cleaning the air filter on a diesel engine equipped with a turbocharger?（）A
Reduce engine speed to idle before removing the filterB
Soak the dirty filter in kerosene onlyC
Blow out the air inlet with compressed airD
Cover the air inlet after removing the filter
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单选题Directional intake ports in diesel engines are used to （）.A
reduce air charge turbulenceB
induce air swirlC
deflect hot combustion gas away from the valvesD
oppose the effects of piston induced squish
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单选题In the cylinder of a diesel engine fuel is ignited by the（）A
spark from a plug in the pre-combustion chamberB
electrical discharge from the distributorC
heat of compression within the cylinderD
heat from the fuel injection nozzle
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单选题The function of diesel engine piston compression rings is to （）.A
prevent piston side thrustB
prevent engine friction lossesC
transmit heat from the piston to the cylinder linerD
remove oil from the cylinder combustion space
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单选题The air required for combustion is taken from the engine room through a filter fitted on the turbochargerThis reduces the risk for too and contamination of the combustion air（）A
high temperaturesB
low temperaturesC
wetD
dirty
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