单选题If a single cylinder relief valve on a diesel engine lists frequently while the engine is running, the cause may be an （）Aexcessively late injection timing for each cylinderBincorrectly adjusted intake valve timingCincorrectly adjusted fuel injectorDincorrectly adjusted intake valve clearance
单选题
If a single cylinder relief valve on a diesel engine lists frequently while the engine is running, the cause may be an （）
A
excessively late injection timing for each cylinder
B
incorrectly adjusted intake valve timing
C
incorrectly adjusted fuel injector
D
incorrectly adjusted intake valve clearance
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相关考题：
If the diesel engine fuel injection timing is changed to delay the start of injection until the pistons are at top dead center, the engine will_________.A.backfire through the air intakesB.develop less power under loadC.have high firing pressuresD.lift its cylinder relief valves
第一组Older loop scavenged engines may have a single injector mounted centrally in the cylinder head. Because the exhaust valve is in the center of the cylinder head on modern uniflow scavenged engines the fuel valves (2 or 3) are arranged around the periphery of the head. The pressure at which the injector operates can be adjusted by adjusting the loading on the spring. The pressures at which the injectors operate vary depending on the engine, but can be as high as 540 bar. Some injectors have internal cooling passages in them extending into the nozzle through which cooling water is circulated. This is to prevent overheating and burning of the nozzle tip. Injectors on modern engines do not have internal cooling passages. They are cooled by a combination of the intensive bore cooling in the cylinder head being close to the valve pockets and by the fuel which is re-circulated through the injector when the follower is on the base of the cam or when the engine is stopped. As well as cooling the injector, re-circulating the fuel when the engine is stopped keeps the fuel at the correct viscosity for injection by preventing it from cooling down. Fuel injectors must be kept in good condition to maintain optimum efficiency, and to prevent conditions arising which could lead to damage within the cylinder. Injectors should be changed in line with manufacturers recommendations, overhauled and tested. Springs can weaken with repeated operation leading to the injector opening at a lower pressure than designed. The needle valve and seat can wear which together with worn nozzle holes will lead to incorrect atomization and dribbling.Modern uniflow scavenged engines have______.A.a single injector mounted in the center of the cylinder headB.several injectors mounted around the external boundary of the cylinder headC.a single injector mounted at the external boundary of the cylinder headD.several injectors mounted in the center of the cylinder head
Fuel is admitted to a diesel engine cylinder through the ______.A.injector nozzlesB.carburetorC.exhaust portsD.intake valves
One cylinder of a diesel engine is persistently knocking and does not cease(停止) when the fuel supply to that cylinder is secured.Which of the following problems may be the cause?A.Low loading of the cylinderB.Excessive cooling of that pistonC.Sluggish ring action on the pistonD.A mechanical defect in a working part
In a diesel engine, late fuel injection is indicated by black or gray exhaust smoke with ______.A.low firing pressureB.low exhaust temperatureC.mechanical knock in each cylinderD.fuel knock in each cylinder
单选题Worn diesel engine intake valve guides can result in （）Aincreased engine breathing efficiencyBexcessive valve lashCexcessive lube oil consumptionDlower than normal fuel consumption
单选题To successfully reduce an excessively high diesel engine exhaust gas temperature, you should （）.Areduce the engine driven fuel pump outlet pressureBretard the fuel injector timing to reduce powerCincrease the fuel rack settingDreduce the load on the engine
单选题The consistent burning of fuel oil with a high sulfur content in a diesel engine will result in （）Aclogged fuel injection pumpsBincreased cylinder liner wearCintake valve stem corrosionDvarnish deposit on pistons
单选题A practical way of checking for excessive fuel injection in one cylinder of an operating diesel engine is to （）Afeel the high pressure fuel lineBcheck the cylinder exhausts for white smoke frequentlyCcheck the cylinder exhaust temperatureDisolate each cylinder and inspect the injector
单选题In a diesel engine, late fuel injection is indicated by black or gray exhaust smoke with（）Alow firing pressureBlow exhaust temperatureCmechanical knock in each cylinderDfuel knock in each cylinder
单选题If a single cylinder relief valve on a main propulsion diesel engine begins to lift, but it is not possible to secure the engine, which of the following actions should be taken?（）AIncrease the cooling water flow to the engineBSecure or reduce fuel to that cylinderCScrew down on the pressure adjusting spring to decrease to decrease popping pressureDReadjust the injection timing
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单选题Significant retardation of a diesel engine fuel injection timing will result in （）Asmoother engine operationBadvanced fuel ignitionCincreased fuel economyDreduced engine power
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