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单选题
Worn main bearing will cause the compression ratio of an auxiliary diesel engine to（）
A
increase
B
decrease
C
remain the same
D
increase on compression decrease on expansion
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音频出入的MAIN口和AUX口说法正确的是()
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单选题Adjust （） by means of lead wire.A
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单选题If the compression ratio is increased on any diesel engine, （）A
the expansion ratio will decreaseB
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单选题A distance piece, with ground faces, may be interposed between the rod and the bearing housing, its thickness being chosen to ensure the correct （）.A
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An increase in compression ratio will increase the ignition lagB
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单选题Measure （） by means of lead wire.A
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单选题Low compression results from （）.A
a worn cylinderB
broken piston ringsC
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单选题The insertion of shims between the foot of a marine type connecting rod and a bearing box would result in （）A
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单选题To determine the main bearing clearance of a propulsion diesel engine, you should measure the main bearing shell using a ball anvil outside micrometer and measure the crankshaft journal using a/an （）A
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ring ‘snap’ gaugeC
inside vernier caliperD
outside micrometer
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单选题Which of the following relationships should occur between the temperature developed in a combustion space, and the compression ratio of the engine?（）A
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Higher temperatures create higher compression ratiosC
low temperatures create higher compression ratiosD
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too light of a loadB
injection timing is too earlyC
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too low of a compression ratio
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greater fuel economyC
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early fuel injectionB
excessive bearing play within the running gearC
overloading of the cylinderD
all of the above
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