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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
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A common trouble with the fuel pump plungers or fuel valve spindle is （）.
A . broken down
B . stuck
C . oil leakage
D . carbonized
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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 intakes
B . develop less power under load
C . have high firing pressures
D . lift its cylinder relief valve
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Problems with the diesel engine fuel injection pump are usually caused by（）
A . improper adjustment
B . contaminated fuel
C . kinked fuel lines
D . excessive engine vibratio
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The effective pump stroke of an individual port-and-helix fuel injection pump is determined by the （）
A . fuel delivery pressure
B . pump plunger diameter
C . plunger control rack position
D . total pump stroke
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During the fuel injection period, fuel pressure must exceed cylinder gas pressure to （）.
A . ensure penetration and distribution of the fuel in the combustion chamber
B . ensure the needle valve is flushed clean during each injection
C . prevent combustion gas blowback into the open needle valve
D . prevent reflected pressure waves when the needle valve close
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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
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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
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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
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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
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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
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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
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The sequence of fuel injection into cylinders is determined by （）.
A . the steering
B . the driven gear
C . the turning gear
D . the timing gear
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Which of the fuel injection systems listed uses a spring loaded differential spray needle valve and individual pump for each cylinder?（）
A . Common-rail injection
B . Air injection
C . Jerk pump injection
D . Distribution injectio
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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
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Because the timing of injection is crucial, （） mounted on the camshaft, which is driven by the crankshaft are used to operate the fuel pumps, one of which is provided for each cylinder.
A . gears
B . rams
C . barrels
D . cam
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The major cause of fuel pump and injection system problems is （）
A . improper adjustments
B . contaminated fuel
C . kinked fuel lines
D . excessive engine vibratio
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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
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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
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Early fuel injection timing is indicated by the cylinder pressure being（）
A . above normal with a below normal exhaust temperature
B . above normal with a normal exhaust temperature
C . below normal with a normal exhaust temperature
D . below normal with an above normal exhaust temperature
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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
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Fuel injection uses the jet pump system and a Woodward type hydraulic （） is used to control engine speed.
A . controller
B . governor
C . instrument
D . apparatu
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Problems with the diesel engine fuel injection pump are usually caused by_____.
A.improper adjustment
B.contaminated fuel
C.kinked fuel lines
D.excessive engine vibration
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The injection pumps are operated by means of （).A.chainsB.fly-wheelC.cams
The injection pumps are operated by means of ().
A.chains
B.fly-wheel
C.cams
