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单选题
During which of the listed piston stroke of a four-stroke/cycle diesel engine, is the piston moving downward?（）
A
Intake stroke
B
Compression stroke
C
Exhaust stroke
D
Pumping stroke
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考题
单选题In a four-stroke/cycle diesel engine, after the completion of the power stroke, the piston will move（）A
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down to burn off fuelC
down to compress the fuel air chargeD
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单选题The four-stroke cycle begins with the piston （）.A
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单选题When an air started, four-stroke/cycle diesel engine is being cranked, the starting air is admitted to each cylinder during what would normally be the（）A
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High lube oil temperaturesC
High vanadium content fuelD
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单选题During the suction stroke, the piston is moving （）.A
inwardsB
outwardsC
downwardsD
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单选题The size of the exhaust valve opening is （）A
most critical in a four-stroke cycle diesel engineB
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考题
单选题Marine four-stroke diesel engines are mainly （）.A
of crosshead typeB
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单选题Which of the two events listed occurs simultaneously in a two-stroke/cycle diesel engine?（）A
Exhaust and scavengingB
Scavenging and compressionC
Ignition and expansionD
Exhaust and compression
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单选题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
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单选题Scavenging in a four-stroke/cycle diesel engine occurs during the （）.A
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考题
单选题A disadvantage of a four-stroke/cycle diesel engine is （）A
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考题
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the crankcase explosionB
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考题
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the same indicated horsepower as a four-stroke/cycle engineB
twice the indicated horsepower as a four-stroke/cycle engineC
one half indicated horsepower as a four-stroke/cycle engineD
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考题
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考题
单选题On a four-stroke diesel engine, when the piston is driven downwards by the expanding gas, it delivers power to the crankshaft through the （）.A
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sounding rodC
connecting rodD
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the suction strokeB
the compression strokeC
the expansion strokeD
the exhaust stroke
考题
单选题During which of the listed piston stroke of a four-stroke/cycle diesel engine, is the piston moving downward?（）A
Intake strokeB
Compression strokeC
Exhaust strokeD
Pumping stroke
考题
单选题In the two stroke diesel engine, it is designed so that the oil impingement is timed to proceed only on the piston ring belt during（）A
compression strokeB
suction strokeC
expansion strokeD
exhaust stroke
考题
单选题Fuel oil begins injection into the cylinder of a four-stroke/cycle diesel engine during the （）.A
intake strokeB
exhaust strokeC
power strokeD
compression stroke
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单选题Which of the devices listed is common to all types of pumps?（）A
A power end and fluid endB
A propeller and educatorC
A volute and impellerD
A turbine and piston
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单选题The average pressure exerted on piston during each power stroke is termed（）A
indicated horsepowerB
mean effective pressureC
exhaust back pressureD
compression pressure
考题
单选题A piston in a four-stroke/cycle diesel engine makes four strokes during each （）.A
crankshaft revolutionB
mechanical cycle of operationC
period of two combustion cyclesD
cycle of two events
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