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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 reservoir
B
a controlling air bottle
C
an emergency air compressor
D
a main air compressor
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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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考题
单选题Vessels having main engines arranged for air starting are to be provided with at least ()A
one automatic drain serving both containersB
two air starting containers of approximately equal sizeC
one control air container and one starting air containerD
one additional means of starting the main engine
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单选题Propulsion engines and the vast majority of auxiliary generator engines are designed to allow a generous through-flow of scavenge air in order to control ()A
the lubricating oil consumptionB
the turbine blade temperatureC
the flow rate of fuelD
scavenge air pressure
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单选题The opening or closing of the cylinder starting valve is controlled by ().A
the starting air distributorB
the cut-off valve on the air mainC
the main starting valveD
the air bottle control valve
考题
单选题Which of the following may cause that an engine doesnt turn on starting air?()A
too low starting air pressureB
main starting valve closedC
neither A nor BD
A and B
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单选题The total starting air capacity required for reversible main engines is to be sufficient for at least ().A
six consecutive startsB
eight consecutive startsC
ten consecutive startsD
twelve consecutive starts
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单选题Which of the following may lead to the engine NOT to start on air?()A
starting air pressure too highB
correct timing of starting air valvesC
three of the six starting valves stuckD
the turning gear disengaged
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单选题Which of the following methods is used to prevent throttling of compressed air through the diesel engine air starting valves?()A
Holding the valve open for a long periodB
Increasing the starting air pressure usedC
Opening the stating air valve quicklyD
Reducing the starting air valve size
考题
单选题Which of the following may cause that an engine doesnt run on starting air?()A
too low starting air pressureB
main start valve closedC
neither A nor BD
A and B
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单选题Main engines as well as auxiliary engines operating on heavy fuel should have continuous on the lubricating oil, either according to the bypass or batch principles()A
filteringB
centrifugingC
depositingD
operating
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单选题Cold weather starting of a diesel engine may be made easier by()A
decreasing the compression ratioB
using a special fuel having a high ignition temperatureC
increasing the starting air supplyD
heating the jacket water
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单选题The booster pump, which supplies diesel oil to() , should have a possibility of being powered by compressed air or by emergency power.A
the main enginesB
the auxiliary enginesC
the emergency generator engineD
the auxiliary engines and the main engine(s)
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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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单选题An electric heater built into some smaller diesel engines is used to ().A
raise lube oil viscosity for easier starting in cold weatherB
increase air inlet temperatureC
increase compression ratioD
increase jacket water temperature for easier starting in cold weather
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单选题When starting air is admitted, a diesel engine turns over very slowly without firingThe cause may be ()A
an obstruction in an cylinderB
water accumulation in some engine cylindersC
low starting air pressureD
low scavenge air pressure
考题
单选题In an operating diesel engine, which of the following condition is an indication of a leaking air starting valve?()A
noise coming from that air starting valveB
continuous operation of the starting air compressorC
zero air pressure in the air starting systemD
overheated starting air pipe to the cylinder head
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单选题The closing of the exhaust valves used on a modern, large, low-speed, main propulsion diesel engine may be directly provided by ().A
large conical springsB
compressed air pressureC
hydraulic pressureD
exhaust gas pressure
考题
单选题When an engine is starting and has got a sufficiently high speed, say about 20 rpm,()A
the starting air supply is cut off and fuel is injected into the cylindersB
the fuel feeding is cut off and the turning gear is put inC
the starting air supply is cut off and turning gear is taken outD
the electric blower is shut down and fuel is injected into the cylinders
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单选题When occurring a fire in the scavenge air box, the following measures should be taken except for()A
reducing speed to SLOW and asking bridge for permission to stopB
stopping the fuel oil supplyC
switching-on the auxiliary blowersD
putting the scavenge air box fire extinguishing equipment into function
考题
单选题An auxiliary reservoir for starting auxiliary engines should be kept at ().A
low pressure at all timesB
full pressure at all timesC
low pressure at intermittenceD
full pressure at intermittence
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单选题Failure to open the diesel engine test cocks after a long period of shutdown, prior to starting may result in ()A
an air bound fuel systemB
damage to cylinder heads and pistonsC
excessive fuel injectionD
excessive air valve lift
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