单项选择题
A.temperature B.viscosity C.lever D.level
If the needle valve in a fuel injection nozzle sticks o...
单项选择题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
If the flame from combustion in the cylinder of a four-...
单项选择题If the flame from combustion in the cylinder of a four-stroke engine past the piston into the space below, the accumulation of flammable mixture would be ignited, thus resulting in （）.
A.the crankcase explosion B.lifting of the cylinder safety valve C.a scavenge fire D.opening of the manhole
If the engine does start on air, but combustion does no...
单项选择题If the engine does start on air, but combustion does not immediately begin, the cause may not be （）.
A.low compression B.failure of the fuel pump to discharge fuel C.incorrect timing of fuel pump D.turning gear being still on
