更多"（）continuously extract the crankcas"的相关试题:
[单项选择]Refrigeration system compressor crankcase sweating is an indication of （）.
A. insufficient lube oil circulating through the system
B. excessive circulation of lube oil through the system
C. insufficient refrigerant in the system
D. an overworked compressor
[单项选择]Internal combustion engine crankcase vent outlets must be equipped with （）
A. hinged rain guards
B. corrosion resistant flame screens
C. dipsticks for measuring oil levels
D. crankcase ventilation fans
[单项选择]A refrigeration system compressor crankcase is sweating or unusually coldThis is an indication of（）.
A. a shortage of refrigerant in the system
B. air in the system
C. an accumulation of liquid refrigerant in the crankcase
D. a shortage of oil in the crankcase
[单项选择]If the refrigeration compressor crankcase is sweating, the cause may be due to （）.
A. a shortage of refrigerant
B. the compressor running continuously
C. liquid refrigerant returning to the compressor
D. the compressor short cycling on the high pressure cutout
[单项选择]A substantial increase in crankcase pressure could be an indication of （）
A. excessive lube oil pressure
B. the proper seating of new rings
C. a worn cylinder liner
D. a malfunctioning cylinder relief valve
[单项选择]An increase in crankcase pressure generally indicates（）
A. worn connecting rod bearings
B. worn engine cylinder liners
C. high cylinder firing pressure
D. stuck spring-loaded manhole covers
[单项选择]If a refrigeration crankcase compressor were short cycling on the low pressure cutout switch, the cause might be that the （）.
A. system was overcharged with refrigerant
B. system was low on refrigerant
C. suction valves were leaking slightly
D. relief valve was leaking slightly
[单项选择]Crankcase explosions in propulsion diesel result from（）
A. the splashing of lubrication oil by the crankshaft
B. the dilution of crankcase oil with particles of combustion
C. broken fuel lines spraying oil on the crankcase
D. the ignition of unburned fuel and air in the crankcase
[单项选择]If a refrigeration system compressor crankcase is sweating, you should （）.
A. add refrigerant to the system
B. adjust the thermal expansion valve to the proper setting
C. adjust the float valve to the proper holding pressure
D. open the hand expansion valve
[单项选择]The blower type crankcase ventilation system （）
A. removes combustible gases in the crankcase
B. prevents the formation of combustible gases in the crankcase
C. cools lubricating oil
D. improves cold weather starting
[单项选择]What function is provided by the crankcase ventilation system on some diesel engines?（）
A. Increases the sludge forming tendency of lube oil
B. Prevents the accumulation of combustible gases
C. Improves lube oil cooling
D. Improves cold weather starting
[单项选择]A diesel engine crankcase ventilation system （）
A. prevents spark generation
B. removes combustible gases
C. determines the level of combustible gases
D. provides inert gas generation in crankcase
[单项选择]An increase in diesel engine crankcase pressure generally indicates excessive（）
A. compression pressure
B. lube oil header pressure
C. scavenge air pressure
D. piston ring blow-by
[单项选择]
With regards to a diesel engine crankcase explosion, the most violent is the（）
(1) primary explosion
(2) secondary explosion
A. (1) only
B. (2) only
C. both (1) and (2)
D. neither (1) or (2)
[单项选择]Crankcase sweating in a refrigeration system is caused by （）.
A. a stuck solenoid valve
B. a shortage of refrigerant
C. too much oil in circulation
D. too much superheat
[单项选择]Excessive oil foaming in the crankcase of a refrigeration compressor at start up can cause（）.
A. compressor damage from improper lubrication
B. refrigerant absorption by the lubricant
C. increased viscosity in the lubricant
D. carbon deposit on the compressor suction valves
[单项选择]If a crankcase explosion occurs in a diesel engine, which of the listed actions should be taken?（）
A. Open the crankcase immediately to check for damage
B. Apply fire fighting water through the crankcase breather
C. Allow the engine to cool before opening the crankcase
D. Assume that there is no damage to the crankshaft
[单项选择]If you notice smoke coming fro the crankcase exhaust fan outlet of an operating diesel engine, you would suspect（）
A. a cracked cylinder liner
B. clogged intake ports
C. broken piston rings
D. a faulty head gasket
