When fuel is injected in a diesel engine cylinder too early,

If fuel injection to a four-stroke/cycle diesel engine begins earlier than designed, ignition may be delayed because the

A.cylinder compression pressure may not be high enough

B.cylinder compression temperature may be too high

C.fuel oil injection pressure may not be high enough

D.scavenge and purge process is incomplete

One cylinder of a diesel engine is persistently knocking and does not cease(停止) when the fuel supply to that cylinder is secured.Which of the following problems may be the cause?

A.Low loading of the cylinder

B.Excessive cooling of that piston

C.Sluggish ring action on the piston

D.A mechanical defect in a working part

Fuel droplets injected into a diesel engine cylinder must have adequate penetration to ____.

A.prolong the ignition delay period

B.ensure the beginning of fuel injection

C.thoroughly utilize the air charge

D.allow controlled fuel combustion

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

High firing pressures and low exhaust temperature in a diesel engine may resultfrom( ).

A.decreased piston to cylinder head clearance

B.increased exhaust system back pressure

C.early fuel injection timing

D.low scavenge air temperature