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单选题
Cracks in cylinder and cylinder covers may （） from unequal heating.
A
make
B
cause
C
result
D
produce
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单选题To function properly, oil control rings used on a diesel engine piston must distribute sufficient oil to all parts of the cylinder wall and must also（）.A
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单选题Fix the fuel injector into （） after repair.A
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单选题Improper cooling of a diesel engine cylinder liner due to the accumulation of scale deposits may cause （）.A
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单选题Diesel engine cylinder head test cocks are used to（）A
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单选题A piston is at bottom dead center when it is（）A
opening the exhaust portsB
closing the fuel portsC
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单选题Pressurized air enters the cylinder via the inlet ports and pushes the remaining exhaust gas from the cylinder in a process known as “（）”.A
chargingB
super chargingC
scavengingD
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单选题The cooling liquid used for the cylinder may be referred to as （）.A
jacket waterB
make-up waterC
boiler waterD
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单选题The cylinder covers are secured by eight elastic holding down arranged in four pairs（）A
nutsB
screwsC
studsD
flanges
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单选题An increase in crankcase pressure generally indicates（）A
worn connecting rod bearingsB
worn engine cylinder linersC
high cylinder firing pressureD
stuck spring-loaded manhole covers
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increased exhaust system back pressureC
early fuel injection timingD
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单选题If water is found in the crankcase of a diesel engine, the cause may be due to（）A
a cracked cylinder headB
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a cracked cylinder linerD
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单选题Persistent knocking of one cylinder of a diesel engine ceases when the fuel supply to that cylinder is securedThis problem may be a result of （）A
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faulty combustion in that cylinderC
sluggish piston ring actionD
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单选题If the flame from combustion in the cylinder of a four-stroke engine past the piston into the space below, the accumulation of flammable mixture would be ignited, thus resulting in （）.A
the crankcase explosionB
lifting of the cylinder safety valveC
a scavenge fireD
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单选题For one or two types of engine,the piston and rod can be withdrawn downwards from the cylinder into the crankcase and then out through （）.A
the cylinder coverB
the bottom of bed-plateC
the sumpD
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单选题For one or two types of engine, the piston and rod can be withdrawn downwards from the cylinder into the crankcase and then out through the （）.A
cylinder casingB
cylinder boreC
crankcase doorD
aperture in the cylinder block
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单选题The function of diesel engine piston compression rings is to （）.A
prevent piston side thrustB
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单选题Piston compression rings used in a diesel engine function to （）A
transfer heat from the cylinder to the pistonB
scrape oil from the sides of the pistonC
seal the combustion space from the crankcasesD
prevent any piston contact with the cylinder liner
考题
单选题The cylinder covers and the liners are bolted together by means of （）.A
bolts welded into the cylinder headB
bolts welded into the cylinder framesC
studs screwed into the cylinder headD
studs screwed into the cylinder frames
考题
单选题The cylinder covers and the liners are bolted together by means of studs （） the cylinder frames.A
screwing intoB
being screw onC
to screw onD
screwed into
考题
单选题Cracks in the cylinders and cylinder covers may （） unequal heating.A
result fromB
result inC
give outD
given from
考题
单选题Cracks in cylinder and cylinder covers may （） from unequal heating.A
makeB
causeC
resultD
produce
考题
单选题A piston is said to be at top dead center when it is （）A
opening the exhaust portsB
placed on top of the engine along its centerlineC
farthest from the cylinder headD
nearest to the cylinder head
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单选题If an inflatable liferaft is overturned，it may be righted by（）.A
filling the stabilizers on one side with waterB
releasing the CO2 cylinderC
pushing up from under one endD
standing on the inflating cylinder and pulling on the straps on the underside of the raft
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