regulate the fuel supply
maintain a constant fuel viscosity at the fuel valves
maintain efficient cooling
alter the fuel density
第1题：
Oil oxidation as a result of excessively high lube oil temperature, is harmful to a diesel engine Because
A.oil foaming will always occur
B.large quantities of oil are consumed
C.lube oil viscosity is always decreased
D.corrosive by-products are usually formed
第2题：
The closing of the exhaust valves used on a modern, large, low-speed, main propulsion diesel engine may be directly provided by_______.
A.large conical springs
B.compressed air pressure
C.hydraulic pressure
D.exhaust gas pressure
第3题：
Proper lubrication of the main bearings is more easily obtained in a single acting, four-stroke/cycle diesel engine than in a tow-stroke/cycle diesel engine because________.
A.The direction of pressure on the journal in four-stroke engine is continuously
B.positive feed lubricators are installed on all bearings of four-stroke engine, whereas as a splash feed system is used on tow-stroke engine
C.four-stroke engines usually utilize a heavier grade of oil than tow-stroke engines
D.Low-stroke engines usually consume less lube oil than four-stroke engines
第4题：
improper adjustment
contaminated fuel
kinked fuel lines
excessive engine vibration
第5题：
A bypass line provided around a waste heat auxiliary boiler in a diesel engine exhaust system, may be used to avoid boiler ______.
A.corrosion at low engine loads
B.erosion at high engine loads
C.overload at high engine loads
D.scaling at all exhaust temperatures
第6题：
Lubrication for the main reduction gears used with diesel engines is usually supplied by
A.oil from the main engine sump
B.an independent lube oil system
C.the stern bearing head tank
D.the stem bearing sump tank
第7题：
In an auxiliary diesel engine bypass type lubricating oil system, the main lube oil pump forces_______ .
A.all of the oil used by the engine through a filter
B.some of the oil used by the engine through a filter
C.some of the oil used by the engine through a centrifuge
D.all of the oil used by the engine through a centrifuge
第8题：
A diesel engine exposed to widely varying ambient temperatures should use to a lubricating oil with .
A.a high viscosity index
B.a low viscosity index
C.neutralize acids
D.resist oxidation at high temperatures
第9题：
temperature
pumping rate
pressure
heat
第10题：
pressure
temperature
viscosity
density