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In the cylinder head of a two-stroke/cycle diesel engine, valves are used for（）
A . air intake
B . a fuel outlet
C . cooling water inlets
D . exhausting combustion ga
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A possible cause for an individual piston to knock when at TDC on a slow-speed, two-stroke/cycle main propulsion diesel engine could be due to （）
A . early fuel injection
B . excessive bearing play within the running gear
C . overloading of the cylinder
D . all of the above
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The main purpose of inspection for a running diesel engine is（）
A . testing for the mechanical load and the thermal load
B . inspecting thermal and mechanical condition of the engine
C . inspecting each system and exhaust temperature
D . testing for compress pressure and explosion pressure
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For a main diesel engine the lube oil in the bearings is drawn from （）, usually located in the bedplate.
A . a gravity tank
B . a sump
C . a vessel
D . a bottle
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Turbocharged four-stroke/cycle diesel engines utilize valve overlap for（）.
A . improving cylinder scavenging
B . preheating the combustion chamber
C . reducing air charge density
D . preventing valve wear
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During maneuvering operations for a direct reversing large, low-speed, main propulsion diesel engine, which of the following actions is used to stop the shaft from turning prior to reversing the engine rotation?（）
A . Flywheel inertia
B . Admission of starting air
C . The way of the vessel
D . securing of fuel to the cylinder
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After changing out the fuel filters the diesel engine fails to restart, the most probable cause for this condition is a/an（）.
A . low compression
B . air-bound fuel system
C . improper spark
D . change in viscosity
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Heat for igniting the fuel oil in the cylinder of a diesel engine is generated by the （）
A . electronic ignition system
B . compression of air by the piston
C . friction in the fuel injector
D . fuel oil bearing system
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A diesel engine which is rated for normal operation at a crankshaft speed of 800 RPM, is commonly classed as a （）.
A . slow-speed diesel
B . medium-speed diesel
C . high-speed diesel
D . constant-speed diesel
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In a closed cooling system for a turbocharged, four-stroke/cycle diesel engine, fluctuating water pressure can be caused by （）
A . improper venting of the cooling system
B . carrying the expansion tank water level too high
C . a totally clogged impeller in the cooling water pump
D . an incorrectly set cooling system temperature control
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When comparing different fuels for different engines, the ignition quality of diesel fuel oils becomes a less critical consideration as （）
A . the amount of lube oil additives increase
B . piston speeds increase
C . injection pressure decrease
D . engine speeds decrease
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Before shutting off the fuel supply to stop a medium or high–speed diesel engine, why is it necessary to allow the engine to idle for a few minutes?（）
A . To prevent internal damage form local overheating
B . To ensure the fuel nozzles are flushed clean
C . To clear the smoke stack
D . To let the waste heat boiler reduce its rate of steam generatio
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For a diesel engine, individual cylinder performance is commonly determined by exhaust gas（）
A . chemical analysis
B . back pressure readings
C . pyrometer readings
D . infrared analysi
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The expansion tank for a diesel engine closed cooling system is designed to maintain a constant head on the system and （）.
A . reduce water temperature
B . reduce water turbulence
C . provide an air cushion
D . allow for an increase in water volume as the engine warms u
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Operating a propulsion diesel engine at less than 30% of designed normal load for prolonged periods will result in （）.
A . decreased fuel consumption per brake horsepower
B . more complete cylinder scavenging
C . extended valve life
D . carbon formation on combustion chamber surface
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The pressure in an operating diesel engine cylinder continues to rise for a short period after the piston passes top dead center as a result of the （）
A . expansion of the combustion gases
B . exhaust and intake valves just closing
C . maximum compression is just being attained
D . fuel injection occurring at that point and combustion begi
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If the coolant temperature of a closed cooling water system for a diesel engine gradually increases, the trouble usually is （）
A . a broken shaft on the freshwater pump
B . an excessive accumulation of scale exchanger
C . an incorrect thermostatic element operating range
D . lube oil in the cooling water
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A four-stroke/cycle, 1000horsepower diesel engine fails to start at normal cranking speed with normal fuel pressure and ambient temperatureThe reason for the failure could be（）
A . glazed liners or pistons
B . high lube oil pressure
C . excessive compression ratio
D . worn valve seats and valve
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If you suspect a diesel engine is misfiring due to air leakage into the fuel system, you should begin looking for the leak at the （）
A . fuel line connections to cylinder injection valves
B . gasket surfaces of the fuel oil filters
C . discharge fitting of the fuel injector pumps
D . suction side of the fuel oil tra
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In a large, low-speed diesel engine the clearance between the piston crown and cylinder head is found to be excessiveIn order to correct for this, you should（）
A . build up the piston crown by metal spraying
B . build up the cylinder head by metal spraying
C . insert shims between the crankpin bearing box and the connecting rod foot
D . install a thinner head gasket
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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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One remedy for a high firing pressure, in addition to a high exhaust temperature in one cylinder of a diesel engine, is to （）
A . increase scavenge air pressure
B . reduce fuel booster pump pressure
C . adjust the fuel rack
D . retard fuel injector timing
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Which of the following statements represents the reason for rolling over a diesel engine with the cylinder indicator cocks open prior?（）
A . To test the starting system
B . To remove air bubbles from the jacket water
C . To ensure that the lube oil system delivers pressure
D . To ensure foreign material (water etc) is not present in the cylinder
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An electrically driven automatically operating auxiliary blower is provided for slow speed and （） of a low speed diesel engine.
A . manoeuvring operations
B . bad combustion
C . cooling
D . mooring trial
