-
Failure of fuel injection is usually due to trouble in the ().
A . exhaust valves
B . mechanical lubricators
C . cooling water pumps
D . fuel injection pum
-
The amount of fuel injected in a particular time, or degree, of crankshaft rotation is termed ().
A . metering
B . timing
C . rate of injection
D . rate of distributio
-
Fuel droplets injected into a diesel engine cylinder must have adequate penetration to ()
A . prolong the ignition delay period
B . ensure the beginning of fuel injection
C . thoroughly utilize the air charge
D . allow controlled fuel combustio
-
A diesel engine will lose power if fuel injection occurs too early because the ()
A . fuel will not be properly atomized in the cylinder
B . ignition will be delayed due to low ignition temperature
C . maximum fuel expansion will occur on the compression stroke
D . fuel will ignite before top dead center
-
When fuel is injected late into a diesel engine cylinder,().
A . the exhaust will be clear
B . fuel consumption will be low
C . all the fuel will be burned at top dead center
D . fuel consumption will be high
-
Significant retardation of a diesel engine fuel injection timing will result in ()
A . smoother engine operation
B . advanced fuel ignition
C . increased fuel economy
D . reduced engine power
-
In a diesel engine, when the fuel is injected into the cylinder,()
A . the piston is just coming upward from the bottom dead center
B . the piston has moved about one-fifth of the way up
C . the piston has moved most of the way up and almost reached the TDC
D . the piston has just past the TDC
-
Dirt lodged on the nozzle valve seat of a fuel injection nozzle will cause()
A . erosion and cratering of the nozzle orifices
B . fuel leakage into the nozzle drain line
C . fuel leakage before and after injection
D . insufficient fuel delivery though that nozzle
-
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 sto
-
If the needle valve in a fuel injection nozzle sticks open ().
A . no fuel will be delivered through the nozzle
B . the nozzle will overheat and crack
C . time of injection will change
D . fuel will leak into the drain line
-
Movement of the pump control rack in a fuel injection system using individual plunger-type pumps ()
A . changes the position of the fuel inlet ports
B . changes the length of the pump stroke
C . varies the quantity of fuel delivered
D . varies the compression of the delivery valve spring
-
The injection may be delayed, ()the pumps are in good order, if the fuel lines to the injection valves have not been cleared of air.
A . because
B . though
C . since
D . until
-
Late fuel injection timing is indicated by ()
A . lower than normal cylinder pressure and low exhaust temperature
B . lower than normal cylinder pressure and high exhaust temperature
C . higher than normal cylinder pressure and low exhaust temperature
D . higher than normal cylinder pressure and high exhaust temperature
-
In a common rail engine, the fuel is injected into cylinders()
A . by injection pumps
B . at a time decided by the injection pump timing
C . by a signal opening the magnetic valves
D . at a time decided by the cam directly
-
Faulty operation of diesel engine fuel injection nozzles can be a direct cause of().
A . excessive fuel nozzle holder cooling
B . sediment in the fuel supply
C . distortion of the fuel spray pattern
D . improper atomization of the fuel
-
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.
A . BHP
B . MCR
C . IHP
D . MEP
-
The operation between two fuel injections is called a working cycle, which consists of a fixed sequence of eventsWhat does "which" mean in this sentence?()
A . a working cycle
B . the operation
C . two fuel injections
D . event
-
Air in the fuel lines to the fuel injection nozzles of a diesel will result in ().
A . lower compression pressures
B . overheating without smoking
C . failure to start
D . a run away without load
-
The fuel injector injects a fine spray of fuel into the hot air and combustion (), producing much high pressure in the gases.
A . has begun
B . takes place
C . occurs
D . happe
-
A diesel engine will lose power if fuel injection occurs too late in the cycle, because the()
A . fuel droplets will burn as they leave the fuel injector
B . fuel will not be properly atomized in the cylinder
C . maximum expansion of the burned fuel cannot take place in the cylinder
D . compression pressure will be too low to cause fuel ignitio
-
If the plunger or barrel of a fuel injection jerk pump becomes damaged,()
A . only the replacement of the entire pump would be acceptable
B . the injection pump and injection nozzle must be replaced
C . either the barrel or plunger must be replaced
D . the barrel and plunger must be replaced as a unit
-
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 line
B . check the cylinder exhausts for white smoke frequently
C . check the cylinder exhaust temperature
D . isolate each cylinder and inspect the injector
-
The diesel engine is a type of internal combustion engine which ignites the fuel by injecting it into hot, high pressure air in a ().
A . air bottle
B . air compressor
C . crank case
D . combustion chamber
-
The purpose of the delivery check valve used in a diesel fuel injection jerk pump is to ().
A . assist in a quick cutoff of fuel injection
B . allow oil backflow from the injector to the helix
C . reduce fuel oil pressure between injection strokes
D . meter the quantity of fuel delivered