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单选题
A diesel engine should not be operated at low loads for long periods of time because（）
A
heavy carbon deposits will buildup on the valves and in the exhaust
B
fuel dilution is increased at low load
C
exhaust valves may be damaged
D
all of the above
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electricB
heatC
mechanicalD
exhaust
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limit engine load
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单选题An over-speed trip stops a diesel engine when the engine （）A
runs out of fuelB
has low lubricating oil pressureC
exceeds a set maximum speedD
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单选题The diesel engine exhaust gas bypass, as fitted with some waste heat boilers, is installed to （）A
prevent engine back pressure at heavy loadsB
increase total engine efficiency at low loadsC
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单选题Starting a large low-speed propulsion diesel engine on diesel fuel during cold weather conditions, will be made easier by （）A
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increasing the lube oil pressureC
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firing loadsC
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单选题Which of the following procedures should be carried out when a large, low-speed, diesel engine is operated with one cylinder secured?（）A
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单选题In order to start a large, low-speed, main propulsion diesel engine on high viscosity fuel after an extended shutdown, the （）A
fuel must be preheatedB
intake air should be preheatedC
lube oil outlet temperature should be increased 20℃ above normalD
none of the above
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单选题Which of the listed diesel engine operating conditions should be checked immediately after any diesel engine is started?（）A
Exhaust temperatureB
Lube oil levelC
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单选题Low compression of diesel engine may result from （）A
a worn cylinderB
broken piston ringsC
any of A and BD
none of the above
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单选题A diesel engine exposed to widely varying ambient temperatures should use to a lubricating oil with （）A
a high viscosity indexB
a low viscosity indexC
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单选题When the normal compression ratio of a diesel engine is not very high, misfiring at light loads may be caused by （）A
overloading the engineB
low exhaust valve liftC
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单选题Burning fuel with a high sulfur content in a diesel engine will （）A
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cause clogging of the fuel systemC
increase the ability of the engine to start in cold weatherD
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单选题What harmful condition can result if a diesel engine is operated at very light loads for long periods of time?（）A
increased carbon buildupB
burning of intake valvesC
excessive firing pressuresD
increased fuel consumption
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increasing the volume of intake airB
shutting off the fuel supplyC
increasing the engine back pressureD
over-speeding the engine
考题
单选题A diesel engine may be hard to start if the （）A
air intake is restrictedB
engine is cranked too fastC
vibration dampener is faultyD
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formation of carbon on the intake and exhaust portsB
high water jacket temperaturesC
overheated pistons and cylindersD
an increase in lube oil viscosity due to fuel dilution
考题
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fuel pump should be removed and all connections blanked offB
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考题
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compression must be low for effective spark ignitionB
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考题
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考题
单选题Which is false about engine trials?（）A
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考题
单选题When running a large, low-speed, main propulsion diesel engine on heavy fuel, which of the following precautions should be observed when switching back over to diesel oil?（）A
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考题
单选题When ship navigating in rough sea, the correct operation is （）A
navigating with a low diesel engine speedB
navigating with a stable diesel engine speedC
increasing the efficiency of propellerD
increasing fuel injection
考题
单选题Misfiring in a diesel engine at light loads can be caused by（）A
high lube oil temperatureB
low lube oil temperatureC
excessive cylinder coolingD
high air injection pressure
考题
单选题Which of the following conditions may need to be reduced when operating a large, low speed, main propulsion, diesel engine at low loads?（）A
Injection pressuresB
Control air supply pressureC
Cooling water flow through after-coolersD
Lube oil temperature
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