自测题

ⅠChoose the best answer for each sentence. 1.Fuel oil is thought to be one of the main factors________the operation and maintenance of an engine. A: have nothing to do with B: having nothing to do with C: have much to do with D: having much to do with 2.Cross scavenging requires the fitting of________to prevent air or exhaust gas escape when the piston is at the top of the stroke. A: a exhaust valve B: a piston skirt C: a piston crown D: an air suction valve 3.In each cylinder cover is a large central opening for mounting____-. A: the indicating cock B: the starting valve C: air inlet valve D: the exhaust valve 4.In a commonly used fuel oil system, the oil is stored in tanks in the double bottom from which it is pumped to________and heated. A: a service tank B: a settling tank C: an expansion tank D: a double bottom tank 5.In an engine with air inlet valve and exhaust valve on its cylinder heads the fresh air will enter into the cylinder________and the gases exhaust ________, there being an adequate overlap between the inlet opening and the exhaust closing. A: downwards/upwards B: upwards/downwards C: downwards/downwards D: upwards/upwards 6.The conclusion that mechanical efficiency is always________100 per cent is correct. A: small than B: more than C: little than D: less than 7.The cleaned heated oil, after passing through the centrifuges, is to be pumped to a________. A: settling tank B: service tank C: ballast tank D: drain tank 8.Oil is supplied to the cylinder wall and________by means of mechanical lubricators. A: the cylinder cover B: the piston rings C: the piston crown D: the piston skirt 9.The common method of applying oil to the cylinder walls is by means of small pump assembled in units , known as________ A: mechanical lubricator B: lubrication function C: forced feed system D: bearing lubrication 10.The diesel engine is a type of internal combustion engine which ignites the fuel by injecting it into hot, high pressure air in a________ A: air bottle B: air compressor C: crank case D: combustion chamber 11.The sequence of parts in a generally used fuel oil supply system for a main engine is________ ①tanks in the double bottom;②centrifuges;③service tank;④settling tank;⑤viscosity regulator. A: ①-②-④-③-⑤B: ①-④-②-③-⑤ C: ①-③-②-④-⑤D: ①-⑤-④-②-③ 1 12.The film of oil between the rings and the liner is not only essential for the lubrication but also plays an important part in achieving________ A: an oil seal B: removing heat C: a gas seal D: cooling the piston 13.The heart of the diesel engine is the________ where the fuel is burnt and the power developed. A: crankcase B: cylinder C: scavenge box D: piston 14.The hot expanding gas rotates the blades of the exhaust turbine, thus giving out large part of its power, which drives________ A: the oil separator B: the fresh water generator C: the compressor D: fire pump 15.The main moving parts of a diesel engine consist of the________and the pistons. A: bedplate, connecting rods B: crankshaft, the connecting rods C: frames, crossheads D: crankshaft, the cylinder 16.The oil quantity for bearing lubrication should be applied in such an amount as to be sufficient to carry away the________ caused by the friction at the bearings. A: acids B: additives C: heat D: gear 17.The position of the piston parts in relation to each other is secured by means of________and a dowel pin in the crown. A: bosses B: through bolts C: machine-turned recesses D: long studs 18.Fuel is admitted to a diesel engine cylinder through the________. A: intake valves B: carburetor C: exhaust ports D: injector nozzles 19.The starting air system usually has________to prevent starting if anything is not in order. A: drain cocks B: vent valves C: counteracts D: interlocks 20.The sealing rings are in four parts and pressed together around the piston rods by means of________ A: nuts B: bolts C: coil springs D: stuffing boxes 21.The working cycle of a four-stroke diesel engine consists of four events;① compression; ②expansion; ③exhaust; ④suction. The correct sequence is________. A: ④-②-③-①B: ④-③-①-②C: ④-③-②-①D: ④-①-②-③22.The expansion tank in a diesel engine closed freshwater cooling system is located at________ A: the highest point in the system B: the lowest point in the system C: near the floor D: plate level or near the tank top level 23.Which of the following will be the function of lubricating oil used in marine engines? A: to remove heat from oil cooled pistons B: to wash away wear detritus C: to neutralize acidic products D: all of the above 24.Which of the substances listed is satisfactorily removed from the fuel by a centrifugal purifier? A: Impurities B: Lube oil C: Gasoline D: Diesel fuel 25.Fuel oil begins injection into the cylinder of a four-stroke/cycle diesel engine during the________ A: intake stroke B: exhaust stroke C: power stroke D: compression stroke 26.Whether using a centrifuge or a simple filter, oil cleaning and filtration will be the most effective when the oil is at a____. A: high temperature and a high viscosity B: high temperature and a low viscosity C: low temperature and a high viscosity D: low temperature and a low viscosity 27.Cooling the intake air supplied to a diesel engine will________ A: reduce mean effective pressure B: decrease average compression pressure C: decrease air charge density D: increase power output 28.The________chamber is enclosed between the cylinder head and piston. A: lubrication B: injection C: cooling D: combustion 29.Camshafts are usually driven by timing gears or____________. A: push rods B: chain drives C: rocker arms D: flywheels 30.________usually helps to induce air movement to assist combustion. A: Cylinder cover B: Main bearing C: The exhaust valve D: The piston movement 31.________allows for expansion and water make up in the water cooling system. A: A top tank B: A head tank C: A head valve D: A drain tank 32.________neutralizes the acid conditions and________ cleanses the tings and grooves. A: The detergency/the alkalinity B: The alkalinity/the detergency C: The inhabitant/the water D: The additives/the distilled water 33.A main bearing consists of two shells which are secured by means of studs and________. A: tie rods B: through bolts C: lead wires D: bearing caps 34.A high temperature alarm or________which will melt is used to guard against the explosion of compressor air pipelines. A: a flame trap B: a relief valve C: a fusible plug D: a bursting cap 35.The outside diameter of the pipe is________the diameter of the bore of the piston rod, the result being that an annular space formed between the piston rod and the pipe. A: less than B: greater than C: equal to D: twice larger than 36.The scavenging air ports are located at_________that they are just exposed by the upper edge of the piston when tile piston is in the bottom dead center position. A: so a height B: such a height C: so high D: such high 37.In any diesel engine closed freshwater cooling system, the lowest pressure exists at the________ A: jacket water outlet B: cooling water pump outlet C: heat exchanger outlet D: expansion tank atmospheric vent 38.For a diesel engine, when the piston is at the____, the clearance volume is the largest. A: TDC B: DTC C: BDC D: DBC 39.High-speed rotating in a centrifugal purifier can produce a force________larger than the force of gravity. A: many thousand times B: between times C: one time D: at times 40.Each cylinder has one starting valve which is usually opened by air pressure and closed by________. A: nuts and bolts B: new joints C: spring force D: sealing rings 41.In the two-stroke engine, inefficient scavenging and other losses reduce____to about 1.8. A: the output B: the oil flow C: the diameter D: the power advantage 42.60. The ---- in the injector will lift at a pre-set pressure which ensures that the fuel will atomize once it enters the cylinder. A: needle valve B: nozzles C: piston D: spring 43.In________ scavenging the incoming air enters at the lower end of the cylinder and exhaust gases are forced out at the top. A: cross B: loop C: aspirate D: uniflow 44.Smaller engines can be made more rigid than large ones and may not have________ A: connecting rods B: crankshaft C: crankcase D: through bolts 45.In the event of the cylinder starting valve leakage____ would pass into the air pipes and ignite the oil deposited. A: cooling water B: vapor from the boiler C: starting air D: hot gases 46.The crank throws are displaced from________to obtained the same number of degrees between the different crank throws. A: one another B: the other C: each other D: each others 47.The fuel oil system for a diesel engine can be considered in two parts:the fuel supply and________ systems. A: fuel treatment B: fuel combustion C: fuel injection D: fuel separating 48.On opposite ends of a single shaft of a turboblower are a gas driven________and a air compressor, which are sealed each other. A: charge air receiver B: scavenging air belt C: turbine D: air cooler 49.The fuel pipes and ducts should be blown with_______. A: atmosphere B: the fresh water C: compressed air D: chemical compounds 50.The pistons of high output engines are often made in two pieces________together to form precisely shaped cooling chambers. A: screwed B: bolted C: welded D: shrunk 51.The cross-head shoes are white metal lined grooves being cut________in the face of the white metal. A: horizontally B: vertically C: slantingly D: crosswise 52.The cylinder and piston must be warmed up________ to a temperature of about 140 deg. F in standing by engine. A: repeatedly B: quickly C: gradually D: immediately 53.The vessel is out of harbor and in "Full Ahead" . We are going to run fuel oil instead of________ and open the fuel oil heater steam valve. A: heavy oil B: lube oil C: fuel oil D. diesel 54.Compressed air is used on board ship________ A: for starting diesel engines B: in pneumatic control system C: in pneumatic tools D: All the above are true. 55.They understand the ____________of automatic sludge discharging of the purifier. But they are not good in practice. A: principle B: principal C: cause D: case 56.The four strokes are called suction, compression, expansion and exhaust, but only________stroke provides the power to drive the ship. A: suction B: compression C: expansion D: exhaust 57.The lower end of each piston rod is reduced in diameter to fit a bore in----, this being secured to the piston rod by a nut. A: the crank-web B: the connecting rod C: the main bearing D: the cross-head 58.Temperature control valves installed in the jacket cooling water system of a diesel engine, modulates the rate of water flow through the-----. A: cooling water pump B: nozzle cooling passages C: cylinder jackets D: heat exchanger 59.Which of the following may cause that an engine doesn't turn on starting air? A: too low starting air pressure B: main start valve closed C: neither A nor B D: A and B 60.On what do you depend having the air cooler of main engine chemically washed? A increased air pressure difference before and aft air cooler B reduced exhaust temperature in all cylinders C reduced temperature difference between water inlet and outlet D both A and C 61.When occurring a fire in the scavenge air box, the following measures should be taken except for________. A reducing speed to SLOW and asking bridge for permission to stop B stopping the fuel oil supply C switching-on the auxiliary blowers D putting the scavenge air box fire extinguishing equipment into function 62.During the watch keeping at sea, routine adjustments should be_____. A made and noted as required by the duty engineer B reported to chief engineer immediately after being made by the duty engineer C never made before getting permission from chief engineer D made as required but not logged. 63.After he _____the test, the engineer put down the results. A. has finished B. finishes C. had finished D. would finish 64.Now that the valve is not worth _____, I suggest it _____. A. to repair/renewing B. repairing/renewing C. to repair/ be renewed D. repairing/be renewed 65.The officer in charge of the engineering watch shall continue to be responsible for machinery operations, _____ the presence of the chief engineer in the machinery space. A. as long as B. unless C. despite D. till 66.I am afraid you can’t dismantle the equipment in that way _____. A. in the case B. in any case C. in no case D. in case 67.The accident resulted _____ the motorman’s carelessness. A. in B. to C. from D. by 68.We'd better _____economic speed _____fuel consumption. A. take/save B. to take/save C. take/to save D. to take/to save 69.When a ship in loaded condition floats at arbitrary water line, its displacement is _____to the relevant mass of water displacement by the ship. A. equal B. larger C. smaller D. equivalent 70.In a diesel engine, when the fuel is injected into the cylinder , _____ A The pisten is just coming upward from the bottom dead center B The pisten has moved about one-fifth of the way up C The pisten has moved most of the way up and almost reached the TDC D The pisten has just past the TDC 71.When the heavy fuel oil is heated to achieve the viscosity of 10-15cST , _____.may occur. To avoid this ,a_____.system is used in most occasions. A boiling and cavitations; low temperature B boiling and cavitations; pressurized C leaking and boiling; low temperature D leaking and boiling;low temperature 72.About the jacket water ,that of the auxiliary engines usually is circulated by _____pumps, and the main engine usually _____ A an engine-driven,as well B an engine-driven,has an independent pump C an independent , as well D an independent , has an independent pump 73.In modern installations, the main engine and standby auxiliary engines _____ A can be started at low temperature and free from preheating B usually are preheatde by steam before being started C are kept at a constant temperature and free from preheating D are kept at a low temperature to save energy 74.A marine diesel engine is started by _____ A supplying high pressure oil into a hydraulic motor B supplying high temperature air into the cylinder C supplying high pressure air into the cylingder D electrical igniting 75.The following options are all the function of lubricating oil except _____ A remove heat and deposits B neutralizing acidic products C lubricating D improving combustiong efficiency 76.When the air charge contacts with the cylinders and pistion and mixes with the residual gases ,it will_____ A increase in temperature B lose its energy partly C expand and do work D begin to be compressed 77.____scavenging means both exhaust ports and scavenging ports are arranged to the same side . A uniflow B cross C loop D straight 78.____of the A-frame there is a strong cast iron frame called the scavenging air box. A At the top B A t the bottom C In the top D In the botoom 79.Usually we take the cooling effect of the air flownthrough the cylinder during the overlap period as ____ A inevitable B harmful C helpfull D unacceptable 80.The starting air entering the cylinder begins when the piston ____ A has nearly come to the TDC B has just past the TDC C has nearly come to the BDC D has just past the BDC 81.When starting an engine , the compressed air enters the cylinder when the corresponding piston is in position of its____ A suction stroke B compression stoke C power stroke D exhaust stroke 82.____fuel oils ____lubricating oils require treatment before passing to the engine A Both /and B Neither /nor C Either/ or D Both/or 83.____less equipment in contact with sea water ,the corrosion problems are much reduced in a central cooling system. A.Because B.With C. Without D. Though 84.____should be taken out,cleaned ,and lifting checked every four to six months. A Piston B Fuel injection valve C Crankshaft D Cylinder cover 85.____on a ship transmits power from the engine to the propeller. A Automatic control system B Speed regularly system C The transmission system D Compression air system 86.____is arranged for cleaning the lubricating oil in the system and clean oil can be provided from a storage tank. A.A filter B.A centrifugal C. A distiller D. A generator 87.____providing lubricating films ,oil used in marine diesel engines have to remove heat from oil cooled piston. A Except for B.Beside C. Except D In addition to 88.A charge of fresh air is drawn into the engine cylinder and then ____by the moving piston____very high pressure. A pressed/to B pressurized/with C pushed/in D compressed/to 89.In the two stroke diesel engine, it is designed so that the oil impingement is timed to proceed only on the piston ring belt during ________. A. compression stroke B. suction stroke C. expansion stroke D. exhaust stroke 90.In a four stroke engine, which process lasts the longest period? A. exhaust and suction process B. suction and compression process C. combustion and exhaust process D. working and exhaust process 91.All three systems have the ports____to swirl the incoming air and direct it in the appropriate path. A angled B rounded C being angled D being arounded 92.After fitting back the gear wheels, do not forget____them. A to grease B greasing C oiling D lubricating 93.Adjust ____ by means of lead wire. A the clearence of the main bearing B the diameter of main bearing C the gap of main bearing D the tolerance of main bearing 94.For an ordinary four-stroke engine the exhaust valves close____ A after TDC B before TD C C after BDC D before BDC 95.For an ordinary four-stroke engine the exhaust valves open____ A after TDC B before TD C C after BDC D before BDC 96.For an ordinary four-stroke engine the inlet valves open____ A after TDC B before TD C C after BDC D before BDC 97.For an ordinary four-stroke engine the inlet valves close____ A after TDC B before TD C C after BDC D before BDC 98.Head tank should be used to remove____from cooling water. A scale B sludge C chemicals D air 99.In two-stroke engine the crankshaft is connected with ___by means of the connecting rod. A the stuffing box B the piston C the cross-head Dguide plate 100. A ____-- is the foundation of the engine, without the support of which the shaft alignment in particular, and engine structure as a whole, would inevitably be lost. A: Frame B: Bedplate C: Cylinder D: Liner 101. ____-is sometimes used for piston cooling since leaks into the crankcase would not cause problems. A: Diesel oil B: Hydraulic oil C: Lube oil D: Mineral oil 102. A distance piece, with ground faces, may be interposed between the rod and the bearing housing, its thickness being chosen to ensure the correct________. A: expansion ratio B: pressure ratio C: compression ratio D: clearance ratio 103. ____supplies pilot air to control the cylinder air start valves. A: An air compressor B: An indicator cock C: An air distributor D: A safety valve 104. All the rings are slightly rounded on their external top and bottom edges to keep the oil film on the cylinder liner during________ for new piston rings. A: the running-in period B: the running process C: gas exchange process D: being rounded 105. Cooling of engines is achieved by________a cooling liquid around internal passages within the engine. A: flowed B: flowing C: mixing D: circulating 106. After the engine is warmed, we should ________the turning gear before starting up the engine. A: take in B: put in C: take out D: put up 107.________the supercharge pressure is, ________power an engine develops. A The higher/the more B Higher/more C Higher/little D The higher/the less 108. In order to keep the oil film on the cylinder liner during the running-in period , the pistion ring are slightly rounded_____. A on both the external and internal top edge B on both the external top and bottom edges C on both the external and internal bottom edges D on all the four edges 109. After”F.W.E”is given,the air system is shut down,the _______gear put in,all drains and indicator cocks opened,and the cooling water kept running. A steering B timing C turning D running 110. _______at the end of the distribution pipe ensures that adequate pressure is maintained by the pump. A .A relief valve B. An alarm C.A pressure gauge D.A non-return valve