问题：
[单选] The effective stroke of a constant-stroke, individual, fuel injection pump is varied by the （）.
control rack。delivery valve。governor speed。plunger crossbar。
问题：
[单选] The diesel engine valve subjected to most severe conditions of service is the （）.
cylinder exhaust valve。air starting valve。air inlet valve。cylinder relief valve。
问题：
[单选] The lower section of a piston is called the （）.
land。skirt。crown。plate。
问题：
[单选] A change in the degree of fuel atomization in a diesel engine would most greatly affect （）.
air turbulence。fuel penetration。fuel spray angle。fuel injection rate。
问题：
[单选] Which of the following devices is a common basic element with nearly all mechanical governors?（）
Power piston。Control rack。Weights acted on by centrifugal force。Isochronous droop spring。
问题：
[单选] Theoretical perfect combustion in a diesel engine yields by-products of （）.
aldehydes and carbon dioxide。water vapor and carbon monoxide。nitrogen and carbon monoxide。water vapor and carbon dioxide。
问题：
[单选] In a bypass type lubrication system for a diesel engine, the dirty oil line to the centrifuge should be taken from the （）.
lube oil pump suction line。lube oil pump discharge line。bottom of the lube oil sump。outlet from the lube oil header。
问题：
[单选] Diesel engine exhaust temperatures may be used to indicate （）.
leaking exhaust valves。an overloaded cylinder。a clogged injector nozzle。all of the above。
问题：
[单选] What is the term given to the process of breaking up fuel oil into very fine particles for better combustion?（）
Settling。Straining。Spraying。Atomizing。
问题：
[单选] Turbulence in a diesel engine cylinder is of major importance in providing （）.
proper fuel metering。complete fuel/air mixing。minimal fuel penetration。proper fuel timing。
