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In an operating diesel engine, which of the following condition is an indication of a leaking air starting valve?（）
A . noise coming from that air starting valve
B . continuous operation of the starting air compressor
C . zero air pressure in the air starting system
D . overheated starting air pipe to the cylinder head
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Excessive piston ring wear in a diesel engine will cause（）
A . high lube oil viscosity
B . increased lube oil consumption
C . low lube oil temperatures
D . high firing pressure
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Valve lash, or clearance refers to the （）
A . clearance between the top of the valve stem and the rocker arm
B . compression of the valve springs
C . clearance between the valve seat inserts and the head
D . out of roundness of the fuel injection cam
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Excessive alkalinity of the water in an auxiliary boiler can cause （）.
A . caustic embrittlement of the boiler metal
B . acidic corrosion of the boiler metal
C . hard scale deposits on the boiler tubes
D . etching of the heat exchange surface
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In an engine with air inlet valve and exhaust valve on its cylinder heads the fresh air will enter into the cylinder （） and the gases exhaust （）, there being an adequate overlap between the inlet opening and the exhaust closing.
A . downwards；upwards
B . upwards；downwards
C . downwards；downwards
D . upwards；upward
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Which of the following will be the advantage of a centrifugal pump as compared with a reciprocating pump?（） (1) Its discharge is continuous (2) It has no internal valves (3) Upon accidental closing of discharge valve, excessive pressure will not build up
A . （1），（2）
B . （2），（3）
C . （1），（2），（3）
D . （2）only
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An orifice-check valve placed in a hydraulic system is used to（）
A . regulate the fluid flow in either direction
B . restrict movement of hydraulic fluid in one direction, but allow free movement in the other direction
C . allow free movement of hydraulic fluid in both directions
D . allow a restricted fluid flow in one direction only
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Excessive oil foaming in the crankcase of a refrigeration compressor can result in （）.
A . overheated compressor bearings
B . excess lube oil viscosity
C . carbon deposits on the compressor piston rings
D . wax crystals forming in the lubricant
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In a four-stroke/cycle diesel engine, badly worn intake valve guides can cause excessive（）.
A . exhaust pressure
B . exhaust temperatures
C . cooling water temperatures
D . lube oil consumptio
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In the common rail system, excessive pressure in the header may be caused by （）
A . improper adjustment of the bypass valve
B . a dribble in the fuel injection nozzle
C . insufficient leak-off through injection nozzle packing
D . a malfunctioning injection nozzle
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A lashing used to secure two barges side by side，lashed in an "X" fashion，is called a （）.
A . scissor wire
B . towing wire
C . breast wire
D . cross wire
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Excessive scale formation in a distilling plant may result from （）.
A . poor distillate quality
B . reduced evaporator capacity
C . low brine concentration
D . improper vacuum regulatio
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A thermostatic expansion valve is properly controlling evaporator superheatAdjusting this valve to lower the superheat will result in a/an （）.
A . evaporator pressure decrease
B . evaporator coil over-feed
C . evaporator capacity increase
D . expansion valve diaphragm rupture
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Excessive vibration in an operating diesel generator may be caused by （）
A . electrical overload
B . surging at governed RPM
C . loose engine mounting bolts
D . coolant leaking into the cylinder
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An axial piston, variable stroke pump is used in a vessels hydraulic steering gearUnder pressure, oil continually leaks out from between the valve plate/cylinder barrel and will（）.
A . cause loss of hydraulic oil from the system
B . result in extreme damage to the pump
C . cause damage to the pump ff not continually drained from the pump casing
D . result in the system high side pressure to substantially drop off
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Where an excessive level of contamination is detected an alarm is sounded and diverting valves are operatedThe discharging liquid is then passed to （）.
A . overboard
B . a bilge well
C . a slop tank
D . a hot well
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Broken valve strips in an operating low pressure, air compressor will cause （）.
A、an immediate crankcase explosion
B、oil contamination in the compressed air
C、a decrease in compressor capacity
D、no immediate loss of the compressed air capacity
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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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If a used lube oil analysis indicates an excessive chromate content, this means （）
A . air filtration is inadequate
B . engine coolant leaking into the lube oil
C . fuel oil is leaking into the lube oil
D . the piston rings are excessively wor
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In an ordinary four-stroke engine the exhaust valves open （）
A . after TDC
B . before TDC
C . after BDC
D . before BDC
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A cutoff valve in the fire-main system of a ship may be closed to protect the portion of the system on an exposed deck from（）.
A . damage from crane operations
B . being used for wash down purposes
C . accidental diversion of flow to wrong location
D . freezing
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Excessive vibration of an automatically fired auxiliary boiler can be caused by （）
A . air or water in the furnace
B . combustion pulses
C . fuel oil pump failure
D . flame failure
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An interlock in the remote operating valve line stops the valve （） when the engine turning gear is engaged.
A . to open
B . opening
C . open
D . opened
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Which of the following may result if an excessive amount of monomer is incorporated into an acrylic resin mixture()
A．excessive expansion
B．excessive shrinkage
C．low impact strength
D．excessive brittleness
