A diesel engines crankcase oil level is found to be too high√ You should suspect that （）.

A . prolonged maintenance intervals B . improved atomization C . greater fuel economy D . incomplete combustio

A . scavenging action of the piston B . piston type vacuum pump taking suction off a differential manometer C . gland exhausting manometer D . crankcase exhaust fa

A . inspection covers should not be opened until the engine has cooled B . ventilation system should be continued in operation for one hour for cooling C . scavenge pump should be immediately secured to prevent loss of lube oil D . explosion covers should be opened slightly to provide extra ventilatio

A . ignition lag B . engine horsepower C . lube oil system pressure D . specific fuel consumptio

A . (1) only B . (2) only C . both (1) and (2) D . neither (1) or (2)

A . has little or no internal friction B . has a lower effective compression ratio C . operates with scavenge air under a positive pressure D . operates without energy absorbing intake and exhaust stroke

A . runs out of fuel B . has low lubricating oil pressure C . exceeds a set maximum speed D . has high cooling water temperature

A . metal particles loosened by wear B . air when no air cleaners are used C . condensation of water vapors D . breakdown of the lubricating oil by dilutio

A . dilutes the lube oil and reduces its viscosity B . forms sulfuric acid in the lube oil C . causes pitting and failure of the bearings D . causes sludge deposits on valve stem

A . a cracked cylinder head B . a leaky cylinder head gasket C . a cracked cylinder liner D . any of the above

A . lower the no-load RPMs B . provide more air for combine with the fuel C . increase the no-load RPMs D . provide more fuel combine with the air

A . free entry of air to the crankcase B . water entering the crankcase while engine wash-downs are being performed C . excessive oil leakage during periods of increased blow-by D . sub-cooling internal component

A . blows out the exhaust gases B . supplies oxygen for combustion C . cools the valves and cylinder walls D . all of the above

A . immediately open all crankcase relief ports B . increase crankcase exhauster speed to draw cool air into the engine C . allow the engine to cool naturally D . increase crank case scavenge air to remove unburned gase

A . lubricating B . cooling C . cleaning D . neutralizing

A . Through the crankcase exhauster B . As water vapor contained in blow-by C . Demulsifying lube oil passing through the main bearings D . Condensation from vapor formed in the expansion tank

A、A. turbine engine B、B. gas turbine C、C. steam engine D、D. internal combustion engine

A . cylinders B . exhaust valves C . pistons D . fuel valve

A . failing to reach rated speed B . knocking under maximum load C . hunting or surging under light load D . overspeeding and running away

A . cross-head B . cylinder C . connecting rod D . spark plug

A . Lube oil is diluted and its viscosity is reduced B . Sulfuric acid is formed C . Bearings become pitted ad immediately fail D . Valve stems develop sludge deposit

A . slam charger B . turbocharger C . fuel atomizer D . fuel injector

A . injecting fuel oil into a cylinder B . removing exhaust gases from the cylinder C . forcing air into the cylinders under pressure after the exhaust valve has dosed D . a combination of all the above

A . increase exhaust back pressure B . causes excessive crankcase pressure C . can only be detected by a compression check D . decreases fuel consumptio