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.

[单选题]If the needle valve in a fuel injection nozzle sticks open （）.A . no fuel will be delivered through the nozzleB . the nozzle will overheat and crackC . time of injection will changeD . fuel will leak into the drain line

[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 faceB . tapered faceC . surfaceD . thinner face

[单选题]The needle valve in the injector （） at a pre-set pressure which ensures that the fuel will atomize once it enters the cylinder.A . will liftB . will be liftedC . will closeD . will be closed

[单选题]If the compensating needle valve of a hydraulic governor is opened more than necessary the governor will .A．have a larger than normal dead bandB．produce excessive speed response to a load changeC．respond slowly to any change in engine loadD．stabilize

[单选题]A． thermostatic expansion valve is properly controlling evaporator superheat. Adjusting this valve to lower the superheat will result in a/anA．evaporator pressure decreaseB．evaporator coil over-feedC．evaporator capacity increaseD．expansion valve diap

[单选题]The expansion valve used in a refrigeration system regulates theA．superheat of the gas leaving the compressorB．back pressure in the evaporatorC．temperature in the refrigerated spaceD．degree of superheat of the gas leaving the evaporator

[单选题]The period of valve overlap is when （）.A . the inlet valve is openB . the exhaust valve is openC . both valves are closeD . both valves are ope

[单选题]Increasing the valve clearance between a valve stem and rocker arm, will result in the valve （）A . closing laterB . opening soonerC . staying open for a shorter period of timeD . staying open for a longer period of time

[单选题]Exhaust valve grooving and corrosion is caused by certain components of residual fuel oilThese components are sodium, sulfur, and （）.A . vanadiumB . carbonC . copperD . ash

[单选题]The opening of an exhaust valve on a modem, large, low-speed, main propulsion diesel engine may be actuated by （）.A . direct action of cam shaftB . compressed air pressureC . hydraulic “push rods”D . direct action of the main piston movin