单选题The crankcase of many diesel engines are kept under a slight vacuum by the （）.Ascavenging action of the pistonBpiston type vacuum pump taking suction off a differential manometerCgland exhausting manometerDcrankcase exhaust fan
单选题
The crankcase of many diesel engines are kept under a slight vacuum by the （）.
A
scavenging action of the piston
B
piston type vacuum pump taking suction off a differential manometer
C
gland exhausting manometer
D
crankcase exhaust fan
参考解析
解析：
暂无解析
相关考题：
An efficient seal between the cylinder block and cylinder heads on many diesel engines is obtained with________.A.graphite packingB.sealing compoundC.lubricating oilD.gaskets
Crankcase explosions in propulsion diesel engines result from ____.A.the splashing of lubrication oil by the crankshaftB.the dilution of crankcase oil with particles of combustionC.broken fuel lines spraying oil on the crankcaseD.the ignition of unburned fuel and air in the crankcase
All diesel engines are classified as ______．A.Four cycleB.Compression ignitionC.Vacuum ignitionD.External combustion
单选题Water accumulating in the crankcase of a diesel engine could indicate（）Aa cracked cylinder linerBexcessive water in the fuelCa leaking intercoolerDexcessive moisture in the scavenge air
单选题Generally，you can best keep a vessel under steering control when the vessel has（）.AHeadwayBSternwayCNo way on，with engines stoppedDNo way on，with engines full ahead
单选题Gear-type flexible couplings are often used in diesel engine drive trains because they（）Arequire no lubrication under normal operating conditionsBcompensate for gross misalignment in the drive trainCare able to transmit high torque ,even where slight misalignment existsDwill rapidly disconnect the engine from the line shaft
单选题If a crankcase explosion has occurred in a diesel engine, and the crankcase remains intact, which of following precautions should be observed?（）AThe cylinder indicator cocks should be openedBThe sump lube oil scavenge pump should be secured immediatelyCThe explosion relief valves should be manually openedDThe crankcase should remain unopened until the engine has cooled
单选题Scuffed cylinder liner wearing surfaces in a diesel engines can result from （）Achromium plating piston ringsBknurling the piston skirtCextended maximum power operationDapplying load to a cold diesel engine
单选题Regarding a Diesel engine crankcase, the general arrangement and installation should preclude the possibility of （）Afree entry of air to the crankcaseBwater entering the crankcase while engine wash-downs are being performedCexcessive oil leakage during periods of increased blow-byDsub-cooling internal components
单选题What function is provided by the crankcase ventilation system on some diesel engines?（）AIncreases the sludge forming tendency of lube oilBPrevents the accumulation of combustible gasesCImproves lube oil coolingDImproves cold weather starting
单选题Diesel engines are considered safer than gasoline engines because（）.Athey are more heavily builtBthe fuel used is less volatileCthey can be easily reversedDthey operate at a lower speed
单选题（）, so they are widely used on board ship nowadays.ADiesel engines have more advantages in comparison with gasoline enginesBDiesel engines have more advantages in comparison to gasoline enginesCGasoline engines have more advantages in comparison with diesel enginesDGasoline engines have more advantages in comparison to diesel engines
单选题Diesel engine ‘blow-by’ into the crankcase is caused by excessive ring（）Aback clearanceBside clearanceCgap clearanceDtaper clearance
单选题In a diesel engine, blow-by（）Aincrease exhaust back pressureBcauses excessive crankcase pressureCcan only be detected by a compression checkDdecreases fuel consumption
单选题The cetane number rates fuels for diesel engines according to its （）Aantiknock characteristicsBignition qualitiesCrates of vaporizationDviscosity
单选题The crankcases of many diesel engines are kept under a slight vacuum to （）Aimprove fuel economyBincrease the air charge velocityCreduce the risk of explosionDall of the above
单选题Crankcase explosions in propulsion diesel result from（）Athe splashing of lubrication oil by the crankshaftBthe dilution of crankcase oil with particles of combustionCbroken fuel lines spraying oil on the crankcaseDthe ignition of unburned fuel and air in the crankcase
单选题If a crankcase explosion occurs in a diesel engine, you should stop the engine and（）Aimmediately open all crankcase relief portsBincrease crankcase exhauster speed to draw cool air into the engineCallow the engine to cool naturallyDincrease crank case scavenge air to remove unburned gases
单选题Some diesel engines are supercharged with a （）Aslam chargerBturbochargerCfuel atomizerDfuel injector
单选题A diesel engine crankcase ventilation system （）Aprevents spark generationBremoves combustible gasesCdetermines the level of combustible gasesDprovides inert gas generation in crankcase
单选题An efficient seal between the cylinder block and cylinder heads on many diesel engines is obtained with（）Agraphite packingBsealing compoundClubricating oilDgaskets
单选题A diesel engines crankcase oil level is found to be too high√ You should suspect that （）.Athe engine was over filledBthere might be a fuel leakCthere might be a water leakDall of the above
单选题How dose water enter the crankcase of a diesel engine?（）AThrough the crankcase exhausterBAs water vapor contained in blow-byCDemulsifying lube oil passing through the main bearingsDCondensation from vapor formed in the expansion tank
单选题All diesel engines are classified as（）.Afour cycleBcompression ignitionCvacuum ignitionDexternal combustion
单选题The main operating characteristic of diesel engines which distinguishes them from other internal combustion engines is the （）Amethod of supplying airBcooling systemCmethod of igniting fuelDvalve operating mechanism
单选题If a crankcase explosion occurs in a diesel engine, which of the listed actions should be taken?（）AOpen the crankcase immediately to check for damageBApply fire fighting water through the crankcase breatherCAllow the engine to cool before opening the crankcaseDAssume that there is no damage to the crankshaft
单选题The responsibilities of the engineer officer in charge of the watch do not include （）Ato ensure the main propulsion plant are kept under constant surveillanceBto ensure the auxiliary systems are kept under constant surveillanceCto inspect the steering gear spaces at suitable intervalsDto inspect and overhaul the equipments in his charge