C． piston skirt D． piston ring belt √
240.In the _____ pressure charging system the pulse of energy that occur as the exhaust is
released from the cylinder to improve the output of the turbocharger. A． constant B． pulse √ C． high
D． none of the above
241.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 √
242.In the four-stroke engine, it takes _____ to make one power stroke.
A． one propulsion B． two propulsions C． two revolutions √ D． one revolution
243.In the sentence “In some designs the cylinder oil is timed so that the oil injects only
on the piston ring belt.”, the \ A． piston crown B． piston ring groove C． piston skirt D． piston ring area √
244.In the suction stroke air is induced into the cylinder _____In the compression stroke
the air is compressed. A． by an fuel valve
B． through an inlet valve √ C． with an exhaust valve D． from an outlet valve
245.Increased air _____ will raise scavenge efficiency and allow a greater mass of air to
be compressed; more fuel may now be burned giving an increased power. A． specific volume B． density √ C． viscosity D． calorific value
246.Increasing differential pressure of an oil filter indicates that _____.
A． it is dirty √
B． it is leaky C． it has been renewed D． all the above
247.Increasing the temperature of a fuel will reduce its _____.
A． viscosity √ B． pressure C． resistance D． setting point
248.It is abnormal that when the engine is being turned by the turning gear or by hand, _____.
A． water discharges from the indicator cocks √ B． no water is leaking into crankcase C． no water in the scavenge belt
D． the rpm is lower than the speed of Dead Slow Ahead
249.It is important that the water _____ very often as this can lead to increased deposits.
A． not be changed √ B． be changed
C． should not be changed D． should be changed
250.It is important to use only pure lead and to choose a thickness of wire which is greater
than the normal allowable clearance but _____ this amount. A． not less than twice
B． greater at least twice than C． not greater twice than √ D． larger three times than
251.It is necessary for us _____ after having served for a certain period.
A． to change the lube oil B． have the lube oil purified C． have the lube oil burnt D． to analyze the lube oil √
252.It is necessary to _____ cool the various components of the machinery so that the engine
can work properly. A． continuously B． regularly C． constantly √ D． period
253.It is necessary to remove _____ from the cooling spaces.
A． scar B． scale √
C． spur D． bilge
254.It is necessary to remove _____ from the cooling water spaces to improve heat transfer.
A． lime B． frost C． scale √ D． scar
255.It is very important that each cylinder should be _____ scavenged before the charged
air is compressed. A． well B． good C． excellent D． respectively √
256.It is very necessary that each cylinder _____ before the charged air is compressed.
A． is scavenged
B． is atomized with fuel oil C． be scavenged √
D． be atomized with fuel oil
257.It is very necessary that each cylinder _____ before the charged air is compressed.
A． is scavenged B． has been scavenged C． be scavenged √ D． was scavenged
258.It is well known that good lubrication will _____ the bearings from becoming overheated.
A． present B． prevent √ C． avoid D． provide
259.Keep compartment _____ as the gas given off can be dangerous.
A． well ventilated √ B． well clean C． in good order D． more room
260.Large marine diesel engines of crosshead construction generally have two systems of
lubrication: a total loss system feeding the _____ and a recirculation system lubricating the running gear and cooling the piston. A． cylinder liners and piston rings √ B． main bearings
C． crankpin bearings D． turboblower
261.Leaky exhaust valve will result in which of the following? (1) high exhaust temperature;
(2) low compression pressure; (3) low firing pressure. A． (1) and (2) B． (1) only C． (2) only
D． (1), (2) and (3) √
262.Low compression of diesel engine may result from _____.
A． a worn cylinder √ B． broken piston rings C． any of A and B D． none of the above
263.Low compression results from _____.
A． a worn cylinder B． broken piston rings C． either A or B √ D． none of the above
264.Lubricating oil for an engine is stored at the bottom of the _____, known as the sump
or in a drain tank located beneath the engine. A． sea cheat B． air receiver C． crankcase √ D． water box
265.Main bearings are required to support the crankshaft at each _____.
A． end B． web C． pin D． journal √
266.Marine four-stroke diesel engines are mainly _____.
A． of crosshead type B． of trunk piston type √ C． of low speed type D． all the above
267.Measure _____ by means of lead wire.
A． the clearance of the main bearing √ B． the play of the miler bearing C． the gap of the main bearing D． the tolerance of the main bearing
268.Measure _____ by means of lead wire.
A． the clearance of the main bearing √ B． the diameter of main bearing C． the hardness of main bearing D． the tolerance of main bearing
269.Modern engines _____ exhaust gas driven turbo-chargers to supply pressurized fresh air
for scavenging and supercharging . A． are made of B． are made from C． make use of √ D． are used to
270.Modem engines _____ exhaust gas driven turbo-chargers to supply pressurized fresh air
for scavenging and supercharging. A． make use of √ B． have made the use of C． by means of D． make advantage of
271.Modem engines make use of exhaust gas driven turbo-chargers to supply pressurized fresh
air for _____ and supercharging. A． scavenging √ B． starting C． cooling D． blowing
272.No specific period is given for the renewal of the lubricating oil filter element as
this should be done_____ a figure of 0.7 bars is shown on the gauge. A． whatever B． whenever √ C． wherever D． whoever
273.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
274.Oil pressure in the lubrication system is _____ the static sea water head to ensure that
sea water _____ the stem-tube. A． lower than / can lubricate B． lower than / can cool C． higher than / can enter D． higher than / cannot enter √