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
Excessive diesel engine back pressure may be an indication of （）
A
carbon buildup in the exhaust manifold
B
overcooling of the exhaust manifold
C
eroded muffler baffle plates
D
high injection pressure
参考答案
参考解析
解析：
暂无解析
更多 “单选题Excessive diesel engine back pressure may be an indication of （）A carbon buildup in the exhaust manifoldB overcooling of the exhaust manifoldC eroded muffler baffle platesD high injection pressure” 相关考题
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
If a diesel engine turned over freely but failed to start, the cause could be ________.A.water in the fuelB.cold lube oilC.excessive starting air pressureD.excessive fuel pressure
考题
单选题An increase in diesel engine crankcase pressure generally indicates excessive（）A
compression pressureB
lube oil header pressureC
scavenge air pressureD
piston ring blow-by
考题
单选题Black smoke exhausting from an operating diesel engine is an indication of poor combustion which may be caused by （）A
water in the fuelB
insufficient fuel for combustionC
clogged air intake passagesD
burning lubricating oil
考题
单选题If a diesel engine starts firing, but is unable to come up normal speed, either without load or even under a small load, the cause may be （）A
insufficient fuel supplyB
faulty governorC
high exhaust back pressureD
all of the above may cause this problem
考题
单选题Excessive vibration in an operating diesel generator may be caused by （）A
electrical overloadB
surging at governed RPMC
loose engine mounting boltsD
coolant leaking into the cylinder
考题
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
prevent boiler corrosion at low engine loadsD
improve engine fuel consumption at any load
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A diesel engine may fail to start due to （）A
low air charge temperatureB
high cranking speedC
excessive fuel dilution of lube oilD
high compression pressure
考题
单选题An auxiliary diesel engine may fail to start due to（）A
low exhaust back pressureB
high lube oil temperatureC
insufficient cranking speedD
excessive fuel atomization
考题
单选题In a diesel engine, blow-by（）A
increase exhaust back pressureB
causes excessive crankcase pressureC
can only be detected by a compression checkD
decreases fuel consumption
考题
单选题Proper lubrication of the main bearing is more easily obtained in a single acting four-stroke/cycle diesel engine than in a single acting two-stroke/cycle diesel engine because （）A
bearing pressure in a four-stroke/cycle acting single diesel engine is continually reversedB
bearing pressure in a two-stroke/cycle single acting diesel engine is continually reversedC
the maximum bearing pressure is higher in a single acting two-stroke/cycle diesel engineD
two-stoke/cycle diesel engines require more complicated lubrication piping
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
exhaust back pressure is low
考题
单选题Exhaust valve openings in a diesel engine cylinder head are made as large as practical to （）A
increase back pressure during the exhaust processB
facilitate periodic replacement of the valvesC
reduce the pumping loss associated with scavengingD
reduce tension on valve springs
考题
单选题Why will a turbocharger diesel engine produce black smoke if excessive additional load is applied too quickly?（）A
Exhaust energy would draw excess airB
The inertia of the turbocharger rotor causes a time lag which delays the turbocharger speed increaseC
Exhaust gas pumping losses are increased due to turbine windageD
Exhaust gas back pressure falls slightly due to increased nozzle action
考题
单选题If a diesel engine is smoking excessively under load, the cause could be （）A
low exhaust back pressureB
early fuel injection in one of the cylindersC
compression pressure in one of the cylindersD
plugged injector holes
考题
单选题Injection lag in a diesel engine may be caused by（）A
a higher cetane number of fuel oilB
the diesel fuel used having a high viscosityC
mechanical rigidity in the lube pump mechanismD
a decrease rigidity in the fuel pump delivery pressure
考题
单选题If fuel injection to a four-stroke/cycle diesel engine begins earlier than designed, ignition may be delayed because the （）.A
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
单选题Any increase in the exhaust back pressure of a four-stroke/cycle diesel engine will （）.A
reduce engine horsepower outputB
aid in silencing the exhaust noiseC
increase the mean effective pressureD
contribute to effective cylinder scavenging
考题
单选题An automated diesel engine should normally shut down due to （）A
low lube oil temperatureB
high ambient air temperatureC
low tube oil pressureD
high exhaust system back pressure
考题
单选题If an auxiliary diesel engine frequently stalls, the trouble may be caused by （）A
low exhaust back pressureB
air in the fuel systemC
gasket blow-by or leakageD
incorrect assembly of idler springs
考题
单选题Low compression pressure in a diesel engine may be the result of （）A
insufficient fuel supply due to fuel pump valves sticking or leakingB
excessive mechanical clearance between the piston crown and cylinder headC
excessively worn fuel pump plungerD
excessive exhaust back pressure
考题
单选题Diesel engine automated control systems may utilize sensing devices of dual function, with sensing ranges providing both alarm and engine shut down capability.Which of the key points would only require an alarm sensor?（）A
Lube oil pressure and temperatureB
jacket water pressure and temperatureC
Engine over-speedD
Lube oil sump level
考题
单选题When starting air is admitted, a diesel engine turns over very slowly without firingThe cause may be （）A
an obstruction in an cylinderB
water accumulation in some engine cylindersC
low starting air pressureD
low scavenge air pressure
考题
单选题In an operating diesel engine, which of the following condition is an indication of a leaking air starting valve?（）A
noise coming from that air starting valveB
continuous operation of the starting air compressorC
zero air pressure in the air starting systemD
overheated starting air pipe to the cylinder head
考题
单选题An indication of a diesel engine air intake being partially clogged, is （）.A
low firing pressure and low exhaust temperaturesB
low firing pressure and normal exhaust temperaturesC
high firing pressure and low exhaust temperaturesD
high firing pressure and high exhaust temperatures
考题
单选题The closing of the exhaust valves used on a modern, large, low-speed, main propulsion diesel engine may be directly provided by （）.A
large conical springsB
compressed air pressureC
hydraulic pressureD
exhaust gas pressure
热门标签
最新试卷
