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单选题
The needle valve will open when the fuel pressure acting on the needle valve （） exerts a sufficient force to overcome the spring compression.
A
tape face
B
tapered face
C
surface
D
thinner face
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valves will close laterC
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amount of fuel injected will be decreased
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单选题When a refrigeration compressor is in the ‘off’ cycle, the thermal expansion valve will（）.A
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单选题When the heat load begins to increase, the needle valve of an expansion valve will（）A
move in an opening directionB
move in a closing directionC
either open or closeD
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考题
单选题Which of the following problems will occur if the needle valve in a fuel injection nozzle sticks in the open position?（）A
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考题
单选题Which of the fuel injection systems listed uses a spring loaded differential spray needle valve and individual pump for each cylinder?（）A
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单选题In its simplest form the pressure reducing valve is opened or closed by （） which is balanced by the downstream pressure acting on a diaphragm.A
adjusting a nutB
a pre-tensioned springC
any springD
upstream pressure
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单选题The direct acting mechanical governor used with some small diesel engines, controls fuel flow to the engine by（）A
governor flyweight action on a pilot valve which controls fuel injectionB
governor flyweight motion acting on fuel controls through suitable linkageC
positioning a butterfly valve in the fuel delivery system positioningD
a servomotor piston attached to the fuel controls
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the compressor to huntC
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