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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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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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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
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The fuel injection pumps on a diesel engine are controlled by a linkage system attached to the ()
A . camshaft
B . crankshaft
C . governor
D . flywheel
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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 load
B . maintaining the metering adjustment for a reasonable period under all load conditions
C . timing fuel injection to obtain maximum power and good fuel economy
D . distributing the fuel to all parts of the combustion chamber for proper combustio
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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, the time taken to heat the fuel particles, turn them into vapor, and bring about combustion is called ()
A . injection lag
B . ignition delay
C . compression
D . turbulence lag
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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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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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Besides heat, fuel, and oxygen, which of the following is necessary for a fire to exist?()
A . Chain reaction
B . Thermal action
C . Chemical occlusion
D . Pyrotechnical reactio
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Fuel has to be injected into the engine at a high pressure so that it () correctly.
A . is purified
B . in timed
C . is compressed
D . atomize
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With VIT unit the timing of fuel injection of an engine can be regulated automatically according to the ().
A . ship draft
B . pitch
C . engine load
D . oil viscosity
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It should be evident that the amount of fuel injected into the cylinder is dependent on the position of the helix relative to the ().
A . inlet port
B . exhaust port
C . spill port
D . scavenge port
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Heat damage to fuel injection nozzles on small high-speed diesel engines, can be prevented by()
A . employing fuel oil as a cooling medium
B . preventing hard carbon deposit on nozzle tips
C . avoiding fuel oil temperature exceeding builder’s specification
D . ensuring good metallic contact between nozzles and cylinder head
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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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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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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
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Heat energy is a source of power, but () will cause damage to the engine.
A . excessive heat
B . insufficient heat
C . effective cooling
D . high output
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What is required in addition to the heat,fuel,and oxygen of the fire triangle to have a fire?()
A . Electricity
B . Chain reaction
C . Pressure
D . Smoke
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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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The burning of the fuel adds more heat to the air charge, causing it to expand and force the engine piston to do work on the crankshaftWhat does “it” mean in this sentence?()
A . the burning
B . the fuel
C . the air charge
D . the engine pisto
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To minimize the formation of carbon deposits on fuel injection nozzles, you should ()
A . avoid using liquid-cooled nozzles whenever possible
B . avoid low cooling water temperatures
C . avoid prolonged overloading of the engine
D . make certain the gasket seal between the nozzle and cylinder head is tight