网友您好, 请在下方输入框内输入要搜索的题目:

题目内容 (请给出正确答案)
单选题
The amount of fuel injection into a diesel engine cylinder by a unit injector, is controlled by()
A

the firing pressure in the cylinder

B

a metering helix inside the pump

C

varying the physical length of the plunger stroke

D

varying the clearance between the injector cam and the injector rocker arm


参考答案

参考解析
解析: 暂无解析
更多 “单选题The amount of fuel injection into a diesel engine cylinder by a unit injector, is controlled by()A the firing pressure in the cylinderB a metering helix inside the pumpC varying the physical length of the plunger strokeD varying the clearance between the injector cam and the injector rocker arm” 相关考题
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

考题 High firing pressures and low exhaust temperature in a diesel engine may resultfrom( ).A.decreased piston to cylinder head clearanceB.increased exhaust system back pressureC.early fuel injection timingD.low scavenge air temperature

考题 If you suspect a diesel engine is misfiring due to air leakage into the fuel system, you should begin looking for the leak at theA.fuel line connections to the cylinder injection valvesB.gasket surfaces of the fuel oil filtersC.discharge fittings of the fuel injector pumpsD.suction side of the fuel oil transfer pump

考题 If fuel injection to a four-stroke/cycle diesel engine begins earlier than designed, ignition may be delayed because theA.cylinder compression pressure may not be high enoughB.cylinder compression temperature may be too highC.fuel oil injection pressure may not be high enoughD.scavenge and purge process is incomplete

考题 One of the factors limiting the amount of toad which can be put on a modem marine diesel engine is the_______.A.governor sensitivityB.exhaust temperatureC.fuel injection pressureD.speed of the cam shaft

考题 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

考题 单选题Problems with the diesel engine fuel injection pump are usually caused by()A improper adjustmentB contaminated fuelC kinked fuel linesD excessive engine vibration

考题 单选题A practical way of checking for excessive fuel injection in one cylinder of an operating diesel engine is to ()A feel the high pressure fuel lineB check the cylinder exhausts for white smoke frequentlyC check the cylinder exhaust temperatureD isolate each cylinder and inspect the injector

考题 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 cylinderB incorrectly adjusted intake valve timingC incorrectly adjusted fuel injectorD incorrectly adjusted intake valve clearance

考题 单选题Diesel engine fuel oil contamination often results in ()A governor malfunctionsB fuel injection system malfunctionsC high cylinder lube oil temperaturesD low intake temperatures

考题 单选题A drop in compression pressure in one cylinder of a diesel engine can be caused by()A a leaking fuel injection nozzleB a clogged air filterC early fuel injectionD burned valves

考题 单选题The term “proper metering”, as applied to a diesel fuel injection system, can be best defined as ().A delivering the same quantity of fuel to each cylinder for each power stroke according to engine loadB maintaining the metering adjustment for a reasonable period under all load conditionsC timing fuel injection to obtain maximum power and good fuel economyD distributing the fuel to all parts of the combustion chamber for proper combustion

考题 单选题High firing pressures and a low exhaust temperature in a diesel engine may result from ().A decreased piston to cylinder head clearanceB increased exhaust system back pressureC early fuel injection timingD low scavenge air temperature

考题 单选题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

考题 单选题The rate of fuel injection in a diesel engine cylinder depends primarily on ().A the size of the holes in the fuel nozzleB timing of the pumpC supply pressure to the pumpD shape of the combustion chamber

考题 单选题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

考题 单选题A change in the quality of fuel atomization by a diesel engine fuel injector would be caused by a/an ()A increase in engine speedB increase in cylinder turbulenceC leaking needle valveD reduction in cylinder turbulence

考题 单选题Late fuel injection in a diesel engine is indicated by low firing pressure with()A high exhaust temperatureB low exhaust temperatureC fuel knock in each cylinderD mechanical knock in each cylinder

考题 单选题The amount of fuel delivered for each cycle must be in accordance with the engine load, and the same quantity of fuel must be delivered to each cylinder for each power stroke at that load.Which of the following statements describes this requirement?()A Proper timingB Accurate meteringC Suitable injection rateD Suitable atomization rate

考题 单选题If the firing pressures in a diesel engine are high, although the exhaust temperatures are normal, the cause may be()A early injection timingB worn orifices in the injection nozzlesC worn or scored cylinder linersD using a fuel with too low of a cetane number

考题 单选题Significant retardation of a diesel engine fuel injection timing will result in ()A smoother engine operationB advanced fuel ignitionC increased fuel economyD reduced engine power

考题 单选题Late fuel injection occurring at, or after TDC in a diesel engine is indicated by excessive exhaust smoke and ()A low exhaust temperatureB low firing pressureC fuel knock in each cylinderD mechanical knock in each cylinder

考题 单选题In the cylinder of a diesel engine fuel is ignited by the()A spark from a plug in the pre-combustion chamberB electrical discharge from the distributorC heat of compression within the cylinderD heat from the fuel injection nozzle

考题 单选题If you suspect a diesel engine is misfiring due to air leakage into the fuel system, you should begin looking for the leak at the ()A fuel line connections to cylinder injection valvesB gasket surfaces of the fuel oil filtersC discharge fitting of the fuel injector pumpsD suction side of the fuel oil tran

考题 单选题Fuel oil begins injection into the cylinder of a four-stroke/cycle diesel engine during the ().A intake strokeB exhaust strokeC power strokeD compression stroke

考题 单选题One of function of diesel engine lubricating oil is to ()A induce carbon formation on cylinder wallsB improve fuel penetration in the combustion spaceC form a friction reducing film between mating surfacesD lubricate the fuel injection

考题 单选题Fuel oil injected into the cylinder of a diesel engine just after the piston passes top dead center, will()A increase engine powerB increase engine loadC decrease engine powerD improve fuel economy