Which of the diesel engine components listed increase air density and helps to improve engine operating efficiency?（）

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• Which of the following conditions is realized by the turbo-charging of a previously naturally aspirated diesel engine?（）

  A . Ignition lag increases B . Lube oil system pressure increases C . Brake specific fuel consumption increased D . Mechanical efficiency increaded

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• If the turbocharger failed on an auxiliary diesel engine, which of the following conditions would probably occur?（）

  A . Full power cannot be developed B . The exhaust will contain black smoke C . Complete combustion will be impossible D . All of the above

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• Which of the following statements is correct for the design and installation of diesel engine cooling water systems?（）

  A . An alarm device with audible and visible signals is required for all cooling water systems B . Propulsion engines with bores over 200 mm are to be fitted with cooling water jackets C . Each totally enclosed cooling system shall be provided with a suitable head tank D . Drain cocks are to be provided at the lowest points of all cylinder water jacket

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• Which of the following statements is true regarding the installation of piston rings on two-stroke/cycle, diesel engines as compared to four-stroke/cycle, diesel engines?（）

  A . In a two-stroke/cycle engine, the rings run hotter, requiring the end gap to be greater B . Some provision must be made in a two-stroke/cycle engine to keep the rings from binding in the ports C . No gap is required to exist between the ends of the ring when cold in a two-stroke/cycle engine, but a small gap is required in a four-stoke/cycle engine D . The gaps should be staggered on either side of a piston in a two-stroke/cycle engine, while staggering is not necessary in a four-stroke/cycle engine

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• Which of the following reasons represents why the designed compression ratio of a gasoline engine is lower than that of a diesel engine?（）

  A . compression must be low for effective spark ignition B . compression must be low for required horsepower and torque generation C . compression must be low to prevent pre-ignition D . compression must be low to have effective pre-ignitio

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• Before engaging the turning gear and turning the diesel engine, which of the following operation should be done except （）

  A . open the indicator cocks B . supply some LO to cylinder liner wall with lubricator C . put the fuel handle in the "stop" position D . pump up the air bottle

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• Which of the following methods is used to prevent throttling of compressed air through the diesel engine air starting valves?（）

  A . Holding the valve open for a long period B . Increasing the starting air pressure used C . Opening the stating air valve quickly D . Reducing the starting air valve size

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• Which of the listed factors will indicate the most about the ability of a fuel to ignite in a diesel engine?（）

  A . Viscosity B . Sulfur content C . Pour point D . Cetane number

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• Which of the following statements concerning the lubrication of diesel propulsion engines used in vessels over 300 gross tons is most accurate?（）

  A . Lubrication systems using engine driven lube oil pumps do not require any additional independent arrangement when such arrangements have been proven reliable B . The use of engine driven pre-lube pumps is permitted on vessels with propulsion systems developing less than 500 shaft horsepower C . When forced lubrication is used for propulsion engines, one independently driven stand-by pumps is to be provided in addition to the necessary pumps for normal operation D . Lubrication systems where two oil coolers are fitted require a minimum of two temperature control devices which may be actuated by similar sensor

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• Which of the following statements represents the function of the compression rings installed at the top of a diesel Engine piston?（）

  A . Control the amount of lube oil burned in the combustion chamber B . Transmit heat from the piston to the cylinder liner C . Prevent damage to ring groove inserts by acting as a heat dam D . Dissipate combustion chamber gas pressure by channeling it through the ring ga

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• Which of the following problems can cause fluctuating pressures in the closed cooling system of a main propulsion diesel engine?（）

  A . Defective temperature controls in the system B . Cavitation in the cooling water pump C . Opened vent in the cooling system D . Restricted water passages in the engine

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• Which of the following conditions can cause below normal air pressure in the intake manifold of a turbocharged diesel engine?（）

  A . Excessive piston blow-by to the manifold B . Insufficient cooling water flow C . Accumulated water in the air boxes D . Clogged air intake filter

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• In some modern large diesel engines, which of the following is used as the support for the main bearings?（）

  A . Bedplate B . Block C . Base D . Sum

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• In a diesel engine lube oil system, which of the following parts should be lubricated first?（）

  A . Camshaft beatings B . Main bearings C . Piston crowns D . Cylinder wall

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• Which of the following conditions will develop if the flow of ‘raw’ cooling water to diesel engine is obstructed?（）

  A . Air will enter the cooling system B . Carbon will plug the water cooled exhaust manifolds C . The jacket water temperature will rise D . The lube oil viscosity will increase

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• On a ship，the possibility of a blowout makes which type of diesel engine shutdown desirable?（）

  A . Overspeed trip B . Air inlet shut-off valve C . Water injector D . Fuel cutoff valve

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• Which of the following conditions is most likely to occur when unburned fuel contaminates the crankcase of a diesel engine?（）

  A . Lube oil is diluted and its viscosity is reduced B . Sulfuric acid is formed C . Bearings become pitted ad immediately fail D . Valve stems develop sludge deposit

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• Which of the listed diesel engine systems is likely to create the problem of a cylinder regularly misfiring?（）

  A . Lubrication B . Cooling C . Fuel D . Electric ignitio

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• Which of the following conditions could be a cause of excessive fuel dilution of diesel engine lube oil?（）

  A . Leaking fuel injectors B . Lower than normal compression C . Delayed fuel injection D . All of the above are correct

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• Which of the following statements is correct concerning diesel engine cooling water systems?（）

  A . Each engine must have its own engine driven cooling water pump capable of providing cooling for all ranges of operation B . propulsion engines with bores exceeding 200 mm are to be fitted with a means to display the cooling water temperature of each cylinder C . At least two independent sea suctions are to be provided for supplying water to the engine jackets or to the heat exchangers D . Suitable strain are to be fitted between the circulating pumps and heat exchangers when sea water is used for direct cooling

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• The main operating characteristic of diesel engines which distinguishes them from other internal combustion engines is the （）

  A . method of supplying air B . cooling system C . method of igniting fuel D . valve operating mechanism

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• Which of the two events listed occurs simultaneously in a two-stroke/cycle diesel engine?（）

  A . Exhaust and scavenging B . Scavenging and compression C . Ignition and expansion D . Exhaust and compressio

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• Which of the following should always be checked prior to starting a diesel engine?（）

  A . Air filters B . Fuel oil strainers C . Crank case oil level D . Pyrometer reading

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• Which of the following conditions indicates the dilution of diesel engine lube oil by fuel oil？ .

  A.Water discharging from the water outlet of the lube oil purifier B.Fuel oil discharging from the water outlet of the lube oil purifier C.Lube oil discharging from the water outlet of the lube oil purifier D.A change in the lube oil viscosity

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