The needle valve will open when the fuel pressure acting on the needle valve （） exerts a sufficient force to overcome the spring compression.

[单选题]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 jammedB . be openedC . be seatedD . be broke

[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 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]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]When the starting air valve closes on one cylinder, another starting air valve has （） opened on another cylinder whose piston has just commenced its downward stroke.A . justB . nearlyC . merelyD . already

[主观题]when the fuel is provided by the supplier ,what specifications of the oil can you get from the supplier receipt ?

[单选题]Re-circulating the fuel when the engine is stopped can______.①keep the fuel at the correct viscosity ②cool the injectorA．①B．②C．①②D．neither ① nor ②

[单选题]When fuel is injected late into a diesel engine cylinder_______.A．the exhaust will be clearB．fuel consumption will be lowC．all the fuel will be burned at top dead centerD．fuel consumption will be high

[单选题]When the fuel oil is burning in the combustion chamber, it _____.A．gives up large amount of heatB．gives off large amount of heatC．gives up large amount of steamD．gives off large amount of steam