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
A substance found in residual fuels which tends to cause exhaust valve corrosion and grooving, is（）
A
carbon
B
vanadium
C
calcium
D
hydrogen
参考答案
参考解析
解析：
暂无解析
更多 “单选题A substance found in residual fuels which tends to cause exhaust valve corrosion and grooving, is（）A carbonB vanadiumC calciumD hydrogen” 相关考题
考题
The sum of the sensible heat and the latent heat of any substance is known as ______.A.total heatB.residual heatC.specific heatD.superheat
考题
单选题In an engine with air inlet valve and exhaust valve on its cylinder heads the fresh air will enter into the cylinder （） and the gases exhaust （）, there being an adequate overlap between the inlet opening and the exhaust closing.A
downwards；upwardsB
upwards；downwardsC
downwards；downwardsD
upwards；upwards
考题
单选题The burning of fuel oil in a diesel engine having a high sodium content, will cause （）A
corrosion and grooving of exhaust valvesB
corrosion and gumming of the fuel injection pumpC
salt deposits in the exhaust manifoldD
slag deposits in the fuel injection equipment
考题
单选题Which of the listed problems can be a cause of low compression pressure in a diesel engine?（）A
clogged air filterB
compression strokeC
burned exhaust valvesD
all of the above
考题
单选题Which of the following problems represent one possible cause of high lube oil consumption in a four stroke diesel engine?（）A
Worn intake valve guidesB
Pitted pre-combustion chambersC
Loose valve tappetsD
High exhaust back pressure
考题
单选题Petroleum cargo tanks should not be topped off at deck level when loading on a cold day because（）.A
a subsequent temperature rise will cause the cargo to overflowB
air pockets may cause the cargo to bubble out of the ullage holeC
the increased viscosity of the product requires higher loading pressure which increases the chances of a spillD
the tank valve may be stiff and a spill will occur before the valve can be closed
考题
单选题Which of the following may cause that an engine doesnt turn on starting air?（）A
too low starting air pressureB
main starting valve closedC
neither A nor BD
A and B
考题
单选题Icreasing the exhaust valve tappet clearance of a diesel engine will result in the exhaust valve opening （）A
later and closing earlierB
later and closing laterC
earlier and closing earlierD
earlier and closing later
考题
单选题If the relief valve on a diesel engine cylinder lifts, the cause could be due to （）A
liquid in the cylinderB
low compression in the cylinderC
high exhaust temperatureD
poor fuel penetration
考题
单选题Leaky exhaust valve will result in which of the following?（） (1) high exhaust temperature; (2) low compression pressure; (3) low firing pressure.A
(1) and (2)B
(1) onlyC
(2) onlyD
(1),(2) and (3)
考题
单选题Which of the listed conditions will occur if a diesel engine exhaust valve is leaking?（）A
Loss of compression for that cylinderB
Misfiring or rough runningC
Damage to the valveD
All of the above
考题
单选题Exhaust valve grooving and corrosion is caused by certain components of residual fuel oilThese components are sodium, sulfur, and （）.A
vanadiumB
carbonC
copperD
ash
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Which of the following would not cause high suction pressure?（）A
insufficient refrigerationB
leaky suction valvesC
expansion valve stuck openD
suction valve not adjusted properly
考题
单选题A built-up exhaust valve is one in which （）.A
the stem and heads are made of different materialB
low-alloy steel is used throughoutC
a replaceable valve disk is welded to the headD
the self-centering action comes from motion of the valve stem in the guide
考题
单选题The arrangement and shape of the cams on a diesel engine camshaft directly control which of the listed groups of operating conditions?（）A
speed, torque, and horsepower productionB
firing order, valve timing, and valve liftC
fuel consumption, efficiency, and cylinder pressureD
scavenge pressure, compression ratio, and exhaust pressure
考题
单选题Why is it important for fuel oil tanks not to be topped off at the inner bottom level when loading on a cold day?（）A
Increased viscosity of the product needs higher loading pressure, which increases the chances of a spillB
Air pockets may cause the fuel to bubble out of the ullage holeC
The temperature rise of the fuel will cause an overflowD
Fueling valve may become stuck closed and cause the fuel oil to spill before the valve can be opened
考题
单选题Valve overlap is the period during which （）.A
the inlet valve is openB
the exhaust valve is openC
both valves are closedD
both valves are open
考题
单选题The period of valve overlap is when （）.A
the inlet valve is openB
the exhaust valve is openC
both valves are closeD
both valves are open
考题
单选题In a diesel engine, an extremely leaking exhaust valve can cause （）.A
misfiringB
pre-ignitionC
interrupted scavengingD
reduced scavenging
考题
单选题A cracked diaphragm in a thermostatic expansion valve will cause the valve to （）.A
return to a neutral positionB
flood the evaporatorC
openD
close
考题
单选题Which of the conditions listed would cause simultaneous high cylinder firing pressure and low exhaust temperature?（）A
Improper fuel rack positioningB
Lengthy opening of the exhaust valveC
Excessively early injection timingD
Extended light load operation
考题
单选题The diesel engine valve subjected to most severe conditions of service is the （）.A
cylinder exhaust valveB
air starting valveC
air inlet valveD
cylinder relief valve
考题
单选题Which of the following problems would be the probable cause for the faulty operation of a reciprocating air compressor suction valve?（）A
Carbon build up in the piston ring beltB
Faulty operation of a cylinder un-loaderC
Compressor operation in an area of high relative humidityD
Lifting of intercooler rebel valve
考题
单选题Corrosion and grooving on the blade of an exhaust driven turbocharger is caused by certain components of residual fuel oilsThese components are vanadium,sodium, and（）A
copperB
carbonC
hydrogenD
sulfur
考题
单选题In which of the scavenging methods listed will the exhaust valve be located in the cylinder head?（）A
Return-flowB
UniflowC
Cross-flowD
Direct flow
考题
单选题Which of the listed design features is found in an exhaust valve and NOT in an intake valve?（）A
Hard alloy steel constructionB
Beveled edges on the valve headC
Low alloy steel constructionD
Poppet type design
考题
单选题A substance found in residual fuels which tends to cause exhaust valve corrosion and grooving, is（）A
carbonB
vanadiumC
calciumD
hydrogen
热门标签
最新试卷