更多"In a main propulsion turbocharged d"的相关试题:
[单项选择]Diesel engine main and connecting rod precision bearings are made in halvesEach half exceeds one-half the bearing circumference by a small amountThe small amount is termed （）.
A. clearance
B. crush
C. pitch
D. thrust
[单项选择]On a medium-speed main propulsion diesel engine, the crank-pin or crank journal bearings receive lubricating oil from （）.
A. a spindle lubricator
B. an oil jet
C. internal splashing
D. drilled passages in the crankshaft
[单项选择]What is one effect of running a diesel engine at too cool a temperature? （）
A. Buildup of sludge in the lubricating system
B. Excessive fuel consumption
C. Severe heat stresses on mechanical parts
D. Foaming of the lubricating oil
[单项选择]The shape of a cam on a diesel engine determines the valve’s （）
A. point of opening
B. speed of opening
C. lift from its seat
D. all of the above
[单项选择]The main operating characteristic of diesel engines which distinguishes them from other internal combustion engines is the （）
A. method of supplying air
B. cooling system
C. method of igniting fuel
D. valve operating mechanism
[单项选择]If a main propulsion diesel engine hunts excessively at idle speed, you should （）
A. adjusts the idle speed control
B. drain and flushes the governor and replace the oil
C. adjusts the compensating needle valve
[单项选择]The main propulsion diesel engine jacket water temperature rises above normal, with the raw water sea suction and the expansion tank water level being normalWhich of the following problems is most likely the cause?（）
A. Faulty thermostatic bypass valve
B. Eroded zinc pencils in the heat exchanger
C. Steam formation in the expansion tank
D. Excessive leakage from jacket water pump seal
[单项选择]The term medium speed diesel engine is currently taken to mean an engine with an operating rotational speed of （） rpm.
A. below 300
B. above 1200
C. between 300 to 1200
D. below 1200
[单项选择]The cooling water of the diesel engine should be treated, because it has（）
A. alkale scence
B. acidity
C. salinity
D. impurity
[单项选择]The main purpose of starting the diesel engine on air briefly is（）
A. to inspect if the cylinder has the water leakage
B. to expel out the residual water/gas/oil from the cylinder
C. to check if fuel supply is normal
D. A and B
[单项选择]In a normally operating diesel engine, the main cause of lubricating oil contamination in the crankcase is a result of the （）.
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 dilution
[单项选择]On a large low-speed main propulsion diesel engine, lower main bearing wear is usually measured by using a/an （）
A. dial indicator
B. outside caliper
C. bridge gauge
D. tram rod
[单项选择]If an auxiliary diesel engine frequently stalls, the trouble may be caused by （）
A. low exhaust back pressure
B. air in the fuel system
C. gasket blow-by or leakage
D. incorrect assembly of idler springs
[单项选择]For a main diesel engine the lube oil in the bearings is drawn from （）, usually located in the bedplate.
A. a gravity tank
B. a sump
C. a vessel
D. a bottle
[单项选择]In large, low-speed, main propulsion diesel engine, position ring groove wear usually occurs at the（）
A. top of the ring groove
B. back of the ring groove
C. bottom of the ring groove
D. piston ring end clearance
[单项选择]A large, low-speed, main propulsion diesel engine uses sea water to directly cool the （）.
A. cylinder heads
B. exhaust valves
C. scavenging air
D. injectors
[单项选择]Main diesel engine control can be obtained by the bridge （）
A. at any time
B. only after the engine room control station is switched to ‘bridge control’
C. whenever the secondary station is switched to ‘bridge control’
D. whenever the engine side control station is switched to ‘bridge control’
[单项选择]One end of a diesel engine cylinder is sealed by the cylinder head and the other end by the （）
A. crankcase
B. piston
C. cylinder liner
D. crank cheek
[单项选择]If a diesel engine turned over freely but failed to start, the cause could be （）
A. water in the fuel
B. cold lube oil
C. excessive starting air pressure
D. excessive fuel pressure
