单选题When a fuel injection nozzle overheats, which of the problems listed can be expected?（）AThe fuel metering will varyBThe fuel will explodeCThe cylinder head will crackDThe engine will stop
单选题
When a fuel injection nozzle overheats, which of the problems listed can be expected?（）
A
The fuel metering will vary
B
The fuel will explode
C
The cylinder head will crack
D
The engine will stop
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相关考题：
Because the timing of injection is crucial, _____ mounted on the camshaft, which is driven by the crankshaft are used to operate the fuel pumps, one of which is provided for each cylinder.A.gearsB.ramsC.barrelsD.cams
The plunger in a jerk pump is rotated until the release port is uncovered If the port remains uncovered all of the time, which of the listed operations will occur?A.No fuel will be deliveredB.The maximum effective stroke will be attainedC.The fuel delivered to the cylinder will be excessiveD.The injection nozzle will overheat and carbonize
Which of the following problems is the main source of fuel pump and injection system malfunctions?A.Improper lubricationB.Air in the fuel systemC.Coated fuel linesD.Excessive vibration
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_______can be a direct cause of faulty operation of diesel engine fuel injection nozzles.A.Excessive fuel nozzle holder coolingB.Sediment in the fuel supplyC.Distortion of the fuel spray patternD.Improper atomization of the fuel
单选题When the opening pressure of a diesel fuel injector is greater than that specified by the engine manufacturer，the （）Aquantity of fuel injected is decreasedBquantity of fuel injected will always be increasedCstart of injection is advancedDduration of injection will always be greater
单选题Heat damage to fuel injection nozzles on small high-speed diesel engines, can be prevented by（）Aemploying fuel oil as a cooling mediumBpreventing hard carbon deposit on nozzle tipsCavoiding fuel oil temperature exceeding builder’s specificationDensuring good metallic contact between nozzles and cylinder heads
单选题If the needle valve in a fuel injection nozzle sticks open （）.Ano fuel will be delivered through the nozzleBthe nozzle will overheat and crackCtime of injection will changeDfuel will leak into the drain line
单选题Fuels of different qualities may require advancing or retarding the injection timing, in addition to which if the injection timing is advanced when the engine is running at loads below the （）, then a saving in fuel can be achieved.ABHPBMCRCIHPDMEP
单选题Which of the following problems is the main source of fuel pump and injection system malfunctions?（）AImproper lubricationBAir in the fuel systemCCoated fuel linesDExcessive vibration
单选题The knock occurring when a cold diesel engine is started and continues while running at low speed, but stops when the engine reaches normal operating speed and temperature, is（）.Acaused by retarded injection timingBcaused by a mechanical defect in one cylinderCcaused by high fuel injection pressuresDnormal for these conditions
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单选题In the common rail system, excessive pressure in the header may be caused by （）Aimproper adjustment of the bypass valveBa dribble in the fuel injection nozzleCinsufficient leak-off through injection nozzle packingDa malfunctioning injection nozzle
单选题A fuel leak occurs in the high pressure fuel piping between the injection pump and fuel nozzleThis requires immediate repair because of the （）Ahigh cost of fuelBserious fire hazardCpossibility of pollutionDpoor combustion which will occur in that cylinder
单选题Dirt lodged on the nozzle valve seat of a fuel injection nozzle will cause（）Aerosion and cratering of the nozzle orificesBfuel leakage into the nozzle drain lineCfuel leakage before and after injectionDinsufficient fuel delivery though that nozzle
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单选题When a fuel injection nozzle overheats, which of the problems listed can be expected?（）AThe fuel metering will varyBThe fuel will explodeCThe cylinder head will crackDThe engine will stop
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单选题Which of the fuel injection systems listed uses a spring loaded differential spray needle valve and individual pump for each cylinder?（）ACommon-rail injectionBAir injectionCJerk pump injectionDDistribution injection
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单选题When restarting a heavy fuel diesel engine that has been stopped for some time, the engine should（）Aincrease the starting air pressureBuse a higher than normal cranking speedCincrease the fuel injection pressureDuse a fuel having a lower ignition temperature
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