更多"When a fuel injection nozzle overhe"的相关试题:
[单项选择]When fuel oil has seriously contaminated a diesel engine lubricating oil, you should （）.
A. filter to remove the fuel oil
B. use the settler to remove the fuel oil
C. remove the fuel oil by centrifuging
D. drain and then renew the lube oil supply
[单项选择]
When fuel oil is accidentally missed with lube oil which of the following processes can be used to separate them?（）
Ⅰ.filtering
Ⅱ.settling
A. Ⅰ only
B. Ⅱ only
C. either Ⅰ or Ⅱ
D. neither Ⅰ or Ⅱ
[单项选择]When fuel is injected in a diesel engine cylinder too early, （）
A. ignition may be delayed
B. fuel economy is not affected
C. exhaust gas temperature will be unchanged
D. the exhaust will be clear
[单项选择]When fuel is injected late into a diesel engine cylinder,（）.
A. the exhaust will be clear
B. fuel consumption will be low
C. all the fuel will be burned at top dead center
D. fuel consumption will be high
[单项选择]When fuel enters the crankcase of a diesel engine, it （）
A. dilutes the lube oil and reduces its viscosity
B. forms sulfuric acid in the lube oil
C. causes pitting and failure of the bearings
D. causes sludge deposits on valve stems
[单项选择]Air in the fuel lines to the fuel injection nozzles of a diesel will result in （）.
A. lower compression pressures
B. overheating without smoking
C. failure to start
D. a run away without load
[单项选择]Dirt lodged on the nozzle valve seat of a fuel injection nozzle will cause（）
A. erosion and cratering of the nozzle orifices
B. fuel leakage into the nozzle drain line
C. fuel leakage before and after injection
D. insufficient fuel delivery though that nozzle
[单项选择]The lowest temperature at which fuel combustion becomes self-sustaining in the presence of a source of ignition, is defined as the （）
A. auto-ignition point
B. flash point
C. burning temperature
D. fire point
[单项选择]Indirect cooling of fuel injector nozzle holders for diesel engines is accomplished primarily by （）.
A. heat conduction into the injected fuel oil
B. heat conduction into the water jacket wall
C. water circulation through passages in the holder
D. fuel oil circulation through passages in the holder
[单项选择]Which may ignite fuel vapors?（）
A. Static electricity
B. An open and running motor
C. Loose wiring
D. All of the above
[单项选择]When the fuel oil is burning in the combustion chamber, it （）.
A. gives up large amount of heat
B. gives off large amount of heat
C. gives up large amount of steam
D. gives off large amount of steam
[单项选择]Which of the fuel injection systems listed uses a spring loaded differential spray needle valve and individual pump for each cylinder?（）
A. Common-rail injection
B. Air injection
C. Jerk pump injection
D. Distribution injection
[单项选择]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
[单项选择]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
[单项选择]When separating fuel oil in oil separator, the separating quantity is（） of the real quantity.
A. 100%
B. 80%
C. 1/2
D. 1/3
[单项选择]（） is the temperature at which a liquid fuel gives off sufficient vapor to form an ignitable mixture near its surface.
A. Setting point
B. Dew point
C. Flash point
D. Lean point
[单项选择]In a diesel engine, when the fuel is injected into the cylinder,（）
A. the piston is just coming upward from the bottom dead center
B. the piston has moved about one-fifth of the way up
C. the piston has moved most of the way up and almost reached the TDC
D. the piston has just past the TDC
[单项选择]
When centrifuging heavy fuel oil, an important factor to consider is the （）
(1) flow rate
(2) viscosity of the fuel oil
A. (1) only is correct
B. (2) only is correct
C. both (1) and (2) are correct
D. neither (1) or (2) are correct
