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In setting the valves on a steam-smothering system on a tank vessel，the master control valve to cargo tanks should be（）.
A . open and individual tank valves open
B . open and the individual tank valves closed
C . closed and the individual tank valves closed
D . closed and the individual tank valves ope
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The purpose of the purge valve at the top of the condenser in a refrigerating system is to（）
A . remove any air that may accumulate in the system
B . take out unpleasant fumes from the refrigerant
C . vent off excess refrigerant in an emergency
D . permit opening the refrigerating system for cleaning and inspecting
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In a four-stroke cycle diesel engine the intake valves open （）
A . before TDC and close after BDC
B . after TDC and close after BDC
C . before TDC and close before BDC
D . after TDC and close before BDC
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A more sophisticated pressure reducing valve incorporates a pilot valve which controls the fluid above the valve operating piston in response to downstream pressureThe bold and italic word “which” means （）.
A . a pressure reducing valve
B . a pilot valve
C . an operating piston
D . downstream pressure
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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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In setting the valves on a steam-smothering system on a tanker，the master control valve to cargo tanks should be（）.
A . open and individual tank valves open
B . open and the individual tank valves closed
C . closed and the individual tank valves closed
D . closed and the individual tank valves ope
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A ruptured diaphragm in a thermostatic expansion valve will cause the valve to （）.
A . open
B . close
C . remain in its position
D . flood the evaporator with refrigerant
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If the operating element of a thermostatic valve installed in a diesel engine cooling system malfunctions, it may result in （）
A . a low level in the engine expansion tank
B . excessively high coolant pressure
C . improper temperatures
D . malfunctioning of the jacket water heater
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The intake valves in a diesel engine are reseated by （）.
A . cam followers
B . push rods
C . combustion gases
D . valve spring
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In a full flow type lube oil system, the bypass relief valve will lift due to （）
A . a clogged filter element
B . excessive lube oil pump discharge pressure
C . excessive lube oil flow
D . excessively hot lube oil
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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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The needle valve in a fuel valve will （） when the fuel pressure action on the needle valve tapered face exerts a force lower than that of the spring compression.
A . be jammed
B . be opened
C . be seated
D . be broke
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Increasing the valve clearance between a valve stem and rocker arm, will result in the valve （）
A . closing later
B . opening sooner
C . staying open for a shorter period of time
D . staying open for a longer period of time
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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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The cylinder oil is pumped into the cylinder (via non-return valves) when the piston rings pass the lubricating orifices during （）
A . the upward stroke
B . the downward stroke
C . the power stroke
D . the suction stroke
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In the piping systems of a vessel，what type of valve gives the least resistance to fluid flow when fully open?（）.
A . Globe valve
B . Butterfly valve
C . Gate valve
D . Packless valve
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A cracked diaphragm in a thermostatic expansion valve will cause the valve to （）.
A . return to a neutral position
B . flood the evaporator
C . open
D . close
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Adjustments to the compensating needle valve in a hydraulic governor should be made with the engine at （）
A . maximum power at a normal load
B . maximum power and load under normal conditions
C . half speed and normal temperature
D . normal operating temperature without a load
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The（） is a smaller valve fitted in the auxiliary steam supply line, and is usually of the non-return type.
A . main stem stop valve
B . auxiliary steam stop valve
C . feed check or control valve
D . blow down valve
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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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When a refrigeration compressor is in the ‘off’ cycle, the thermal expansion valve will（）.
A . always be wide open when the compressor restarts
B . continue to operate as if the system were in operation
C . remain open until evaporator pressure equalizes, then close until the compressor restarts
D . always be completely closed until the compressor restart
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The valve best suited for throttling gas or liquid flow in a pipeline is the（）.
A . gate valve
B . globe valve
C . check valve
D . plug cock
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The cylinder oil is pumped into the cylinder （via non-return valves) when the piston rings
The cylinder oil is pumped into the cylinder (via non-return valves) when the piston rings pass the lubricating orifices, during ______.
A.the upward stroke
B.the downward stroke
C.the power stroke
D.the suction stroke
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When a refrigeration compressor is in the ‘off’ cycle, the thermal expansion valve will .
A.always be wide open when the compressor restarts
B.continue to operate as if the system were in operation
C.remain open until evaporator pressure equalizes, then close until the compressor restarts
D.always be completely closed until the compressor restarts
