问题：
[单选] In a diesel engine, excessive cylinder liner wear will cause （） (1) increased blow-by (2) wear between the piston ring and groove
(1) only is correct。(2) only is correct。both (1) and (2) are correct。neither (1) or (2) axe correct。
问题：
[单选] The opening of an exhaust valve on a modem, large, low-speed, main propulsion diesel engine may be actuated by （）.
direct action of cam shaft。compressed air pressure。hydraulic “push rods”。direct action of the main piston moving dow。
问题：
[单选] The power output of a turbocharged diesel engine will drop if the cooling water flow through the after-cooler is interrupted because the （）.
turbocharger stalls。exhaust pressure increases。air charge density decreases。scavenge effect increase。
问题：
[单选] Successful combustion inside the cylinders of a diesel engine is dependent upon （）.
fine atomization。high temperature。good mixing of fuel and air。all of the above。
问题：
[单选] Which of the combustion parameters listed is used in a diesel engine, but NOT related to the injection system?（）
Atomization。Metering。Effective stroke。Penetratio。
问题：
[单选] An advantage of aluminum pistons, when compared to cast iron pistons is （）.
greater high temperature strength。better heat conductivity。greater weight per cubic inch。increased resistance to wear。
问题：
[单选] Improper cooling of a diesel engine cylinder liner due to the accumulation of scale deposits may cause （）.
low compression pressure。increased piston wear。increased cylinder lube oil consumption。poor contact between compression rings and liner。
问题：
[单选] Diesel engine exhaust gas temperatures can be used to determine individual cylinder （）.
performance。horsepower output。fuel consumption。scavenge effect。
问题：
[单选] Which statement about diesel engine combustion is true?（）
Combustion does not begin until the piston starts down on the power stroke。Maximum combustion pressure is reached before TDC。Turbulence in the cylinder causes a delay in ignition。Maximum cylinder firing pressure is not developed until the piston passes TDC。
问题：
[单选] Proper atomization of fuel in diesel engine combustion chambers will （）.
affect the injection pressure。improve combustion。reduce compression pressure。decrease power output。
