Any increase in the exhaust back pressure of a four-stroke/cycle diesel engine will （）.

单项选择题High exhaust temperature and black smoke exhausting from an auxiliary diesel engine can be caused by （）.

A.engine overload
B.low combustion temperature
C.plugged fuel nozzle holes
D.excessive compression pressure

单项选择题On most diesel engines, the governor controls the output speed by （）.

A.controlling the amount of fuel injected into the cylinders
B.varying the speed of the turbocharger
C.adjusting the compression ratio
D.changing the timing of the fuel injection camshaft

单项选择题Which of the following devices is common to both mechanical and hydraulic governors?（）

A.Direct linkage between the ball-head and fuel rack
B.A servomotor
C.A compensating device
D.Flyweights

单项选择题Which term describes piston pins having bearing surfaces in both the piston bosses and connecting rod eye?（）

A.Stationary
B.Full floating
C.Semi-floating
D.Free rolling

单项选择题The longer the ignition delay period occurs in a diesel engine, the （）.

A.less fuel will enter the cylinder
B.lower will be cylinder compression temperatures
C.more complete will be fuel combustion
D.more rapid will be the rise in combustion pressure