1. Which standards govern the specifications for supply of Residual Marine Fuels and Distillate Marine Fuels onboard merchant ships?
A. ISO 3012:1999
B. ISO 3648:1996
C. ISO 8216-1:2010
D. ISO 8217:2010
2. Crank web deflection readings will give a positive indication of
A. worn main bearing journals
B. torsional stress deformation
C. slack thrust bearings
D. bearing shells shim dimensions
3. ESD stands for which type of boiler
A. External superheater D-type
B. Emergency shutdown Boiler
C. Extreme Superheat type
D. External Superheat De-superheater type
4. The advantage of tie rods over an engine without tie rods is that:
A. The engine is very easily aligned after any misalignment has taken place between different components of the engine
B. The engine doesn???t require thrust pads for transmission of thrust to the ship???s hull as the same is being taken care of by the tie rods
C. The engine components are much lighter leading in overall reduction is engine weight with a high power generation with the elimination of fatigue stresses
D. There are no advantages of engines with tie rods, because tie rods require regular maintenance and replacement like connecting rods and overall engine becomes more expensive to operate
5. Which of the following is an example of a solid bearing?
A. Piston pin bushing
B. Turbo-generator turbine bearing
C. Spring bearing
D. Thrust bearing
6. In order for microbiological growths to thrive in a fuel tank it is necessary for
A. high temperatures to exist
B. low temperatures to exist
C. small amounts of water to be present
D. large amounts of water to be present
7. Marine boilers burning H.F.O. face a problem of cold corrosion due to high sulphur content. The minimum flue gas temperature within any boiler part is kept above due point of H2SO4. The actual dew point of H2SO4 in flue gases depends on the:
A. Boiler furnace temperature
B. Ambient air temperature
C. Boiler operating pressure
D. HFO sulphur content and moisture in combustion air
8. The purpose of an air cooler in a supercharging system is to:
A. Reduce temperature of supercharged air in order to condense and remove maximum possible moisture from the air prior entry to the engine
B. Reduce the temperature of the supercharged air in order to increase the density & also to cool down below dew point to remove moisture from air prior entry to the engine
C. Cool supercharged air to increase its density such that the dew point is not reached to avoid entry of moisture into the engine
D. Cool supercharged air to increase it???s density and also to keep the peak temperature and exhaust gas temperature within limits
9. Use of Halon as fire extinguishing medium has been discontinued because
A. It is highly toxic
B. It is expensive
C. It has high Ozone depleting potential
D. It leads to acid rains
10. In comparison to exhaust valves, intake valves of diesel engines may be fabricated from low-alloy steels because
A. the beveled edges of the intake valves provide forself-centering during seating
B. intake valves utilize stellite-coated valve seat insertswhich reduce wear
C. the volume of air passing through intake valves is less than the volume of air passing through exhaust valves
D. intake valves are less affected to the corrosive action of exhaust gases
11. Why is it essential to renew turbocharger bearings after a preset number of hours of running even if the bearings are in seemingly perfect condition?
A. Because they are prone to failure due to prolonged exposure to high temperature conditions.
B. Because they are subject to cyclic loading and are prone to failure due to metal fatigue.
C. It is not essential to renew if condition monitoring suggests perfect condition.
D. Lube oil contamination is bound to occur and affect the condition of the bearings.
12. Which of the following statements is true?
A. The rotary vane type steering gear generally operates at higher oil pressures than the ram type.
B. The ram type steering gear generally operates at higher oil pressures than the rotary vane type.
C. Both ram type and rotary vane type steering gears generally operate at similar oil pressures
D. None of the above
15. Modern marine turbochargers use a ___________ type of compressor
A. Radial flow
B. Axial flow
C. Mixed flow
D. Turbulent flow
16. Which of the following is a disadvantage of water as cooling medium for pistons, when compared to oil?
A. Chemical treatment is required
B. Higher thermal stresses in piston
C. Piston of more complicated design
D. All of the above
17 How is the concentration of dissolved oxygen in the feed water of an auxiliary boiler maintained at acceptable limits?
A. Feed water is cycled through a DC heater.
B. Feed water is treated with phosphates.
C. Oxygen is liberated in the three-stages of feed water preheating.
D. Oxygen is liberated by maintaining the highest practical feed water temperature
18. In a 2-stroke marine diesel engine if the o-ring for Jacket cooling water sealing is leaking then
A. The water will leak directly into the crankcase
B. The water will leak into the under piston space
C. The water will come out through tell-tale hole provided between the two o-rings
D. The water will come out from the top of cylinder jacket
19. The lube oil pump used in a diesel engine is a
A. volute pump
B. centrifugal pump
C. diaphragm pump
D. gear pump
20. Prior to lighting off a cold automatically fired auxiliary boiler, you should
A. check and regulate the water level
B. close the air cock once fires are lit
C. blow down the gage glass
D. crack the steam stop to assure protective steam flow
21. Steam temperature control for the ESD-II boiler is achieved by :
A. Fitting a de-superheater between 1st & 2nd passes of superheater
B. Fitting an attemperator between 1st & 2nd passes of superheater
C. Gas dampers in boiler uptake
D. Bypassing the superheater
22. The coating which is provided on the valve stem of exhaust valves of modern marine diesel engines is of:
23. If the combustion control system of an automatically fired auxiliary boiler fails to sustain burner ignition after a normal shutdown, you should check for a/an
A. faulty photocell detector
B. low steam pressure
C. high voltage on the ignition electrode
D. open air damper
24. Which of the following statements is true, about slow speed engines?
A. A scavenge fire can lead to a crankcase explosion
B. A scavenge fire can lead to deformation of diaphragm plate
C. A scavenge fire can lead to damage to tie rods.
D. All of the above.
25. For a two stroke engine two o-rings are provided on the liner. The function of the top o-ring is to ___________ and function of the lower o-ring is to ____________
A. Seal jacket cooling water; act as secondary seal in case 1st o-ring leaks
B. Seal jacket cooling water, Seal scavenge air
C. Seal scavenge air, Seal Jacket cooling water
D. Seal combustion gases, Seal jacket cooling water
26. Even if there is an oil mist concentration inside a crankcase, and there is also a hot spot, crankcase explosion will only take place when
A. The hot spot provides the ignition temperature for the oil mist concentration
B. When the oil mist - air mixture is in the flammable range
C. Both A and B
D. None of the above
27. Which of the following conditions is responsible for the fuel oil to atomize when using a steam atomizer in an auxiliary boiler?
A. Expansion of the steam in the furnace.
B. Expansion of the steam in the whirling chamber.
C. Expansion of the steam in the orifice plate.
D. All of the above.
28. Some 4-stroke engines are fitted with a rotorcap on the cylinder head valves. For what reason?
A. Rotate the inlet valve during operation.
B. Distribute the exhaust gas or the air inlet better to improve combustion.
C. Improve the scaling surface function, increase the service time of the exhaust valve in the engine
D. To prevent the valve spindle from sticking
30. Shaft tunnel requires
b) escape trunk
c) water tight door
d) all the above
31. What do you mean by surge limit of a turbocharger?
A. Characteristic curve of a turbocharger
B. Portion of compressor characteristic curve which lies on the left side of the point of maximum pressure
C. A line joining all the points of maximum pressure on compressor characteristic curves , drawn at various speeds of operation
D. Maximum rpm limit of T/C above which surging will start
32. A large, low-speed, main propulsion diesel engine uses sea water to directly cool the
A. cylinder heads
B. exhaust valves
C. scavenging air
33. Exhaust Grouping is required in case of ______________ turbocharging in order to
A. Constant pressure, prevents shockwave generation
B. Pulse pressure, prevent interference with scavenging of other cylinders
C. Constant pressure, prevent interference with scavenging of other cylinders
D. Pulse pressure, prevents shockwave generation
34. Function of a de-superheater is to.
A. Protect superheater from overheat
B. Control superheater steam outlet temperature
C. Increase the efficiency of the boiler
D. Reduce steam temperature for auxiliary uses after steam superheater
35. Which of the following statements is false?
A. Oxidation of lubricant leads to decrease in its viscosity
B. Formation of oxidation acids, sulfuric acid leads to depletion of TBN of lubricant
C. Contamination with water will lead to decrease in the load carrying capacity of a lubricant .
D. Build up of insolubles will lead to increase in viscosity of a lubricant
37. After prolonged operation, jerk type fuel pumps wear on the top edge of plunger and edges of spill ports and helix due to erosion by high pressure fuel as it spills. This wear would result in
A. Late start of injection and early end of injection
B. Early start of injection and late end of injection
C. Early start of injection and early end of injection
D. Late start of injection and late end of injection
38. Labyrinth seal fitted on the back surface of a compressor wheel of a turbocharger:
A. Prevents bearing lube oil contamination
B. Prevents bearing lube oil being sucked into the air stream
C. Helps to keep the shaft cool by controlled leakage of air
D. None of the above
39. It is a known fact that centrifugal pumps require priming for pumping liquids , as they cannot handle air and will lose suction due to air entry . But on the other hand T/Cs use centrifugal compressors for supercharging. Which of the following do you think makes a centrifugal compressor to pump air and behave differently than the centrifugal pumps?
A. Presence of air cooler
B. Presence of Labyrinth seal
C. High speed of rotation, very fine internal clearances and large impeller diameters
D. Difference in principle of operation
40. If an operating auxiliary boiler has a water pH reading of 7, you should
A. bottom blow the boiler
B. treat the water with caustic soda
C. treat the water with chemical scavengers
D. reduce the water alkalinity to recommended readings
41. In case of 2-stroke marine diesel engines, the top part of the liner forming the combustion chamber experiences very high pressure induced mechanical stresses as well as high thermal stresses. Which of the following is a correctly designed liner for catering both the above stresses?
A. Thick top portion with jacket cooling to take care of both the high mechanical and thermal stresses
B. Thick top portion to take care of high mechanical stresses while bore cooling to reduce thermal gradients
C. Thin top portion to reduce thermal gradients and hence thermal stresses while supporting ribs to take care of mechanical stresses
D. Thick top portion to take care of high mechanical stresses with jacket cooling combined with allowance for thermal expansion to minimize the thermal stresses
42. Which of these fuel oil impurities can cause maximum abrasive damage?
C. Catalytic fines
43. In modern marine 2-stroke diesel engines, ________________ is sometimes used as a coating on the underside of the exhaust valve disc, to reduce the rate of hot corrosion.
44. Irregular circumferential wear of liner due to diminishing neutralizing capacity of cylinder oil away from lubricating holes is known as:
A. Micro seizure
D. Clover leafing
45. Which of the following is a reasonable statement about water washing of turbine side of a T/C ?
A. It leads to thermal shock and reduces the life of the T/C
B. It leads to thermal shock and not so effective as solid washing
C. If properly carried out keeping rpm, load, temperature limits & other factors into account; it is quite safe and more effective than solid washing
D. It should never be carried out as most of the engine manufacturers recommend against the same
46. Which of the following statements correctly describes the phenomenon of surging in a 2-stroke crosshead type engine?
A. Due to sudden increase in engine load the exhaust gases may flow back through scavenge ports causing surge
B. Due to sudden decrease in engine load the turbocharger pressure ratio drops . This causes high pressure downstream of T/C in scavenge trunk causing flow reversal of scavenge air
C. Due to sudden increase in engine load , the T/C turbine rpm may increase suddenly increasing the compressor pressure ratio to surge
D. Due to sudden decrease in engine load , the turbocharger may stall as the higher pressure downstream in exhaust system may cause reversal of flow of exhaust gases
47. If the boiler tubes are scaled on the water side then
A. Heat conduction through the tubes will be very high leading to rapid evaporation
B. The boiler furnace can get damaged due to excessive temperatures
C. The surface of the tube will be overheated as heat transfer is impaired
D. The natural circulation of water within the boiler will be more efficient
48. Fins are installed on the generating tube surfaces in waste heat boilers to
(A) Prevent soot fires in the exhaust system
(B) Prevent exhaust gas erosion of the tubes
(C) Increase the velocity of exhaust gas flow
(D) Increase the rate of heat transfer
49. Any steering gear system alarm can only be successfully acknowledged from
A. The bridge
B. The engine control room
C. The steering compartment
D. The ship's office
50. To check the setting of the over speed trip on a diesel powered generator, you would use a
B. torsion meter
D. pony brake
51. Which of the following specifications/qualities of cylinder oils counter corrosive wear?
D. Specific gravity
52. What is meant by elastohydrodynamic lubrication?
A. Formation of hydrodynamic film under high pressure with minor elastic deformation of mating surfaces, distributing load over a greater area
B. Addition of extreme pressure additive (EP) to the lubricant
C. Addition of Viscosity index improvement additive
D. Addition of elastomer based additives
53. In a bypass type filtering system for a medium or high speed diesel engine, the lube oil bypassing the filter
A. returns directly to the suction side of the pump
B. returns directly to the sump
C. flows to the engine bearings
D. flows through a second-stage strainer, reheater, and returns to the sump
54. Which type of boiler burner has max turn down ratio?
a. Pressure set
b. spinning cup
c. Spill type
d. Y-jet type
55. Most steam traps respond well to cleaning. But when a thermodynamic trap fails to operate after cleaning, the next course of action should be
A. throttle the steam outlet valve
B. renew the trap
C. lap the disc and seat the trap
D. throttle the steam inlet valve
56. Types of corrosion in fresh water of D/E
b. hot corrosion
d. selective phase corrosion
57. Which of the following types of damages are metal seatings of a valve subject to? Choose the correct alternative.
A. Corrosion, Erosion, Abrasion, Deformation
B. Corrosion, Fatigue failure, brittle fracture, caustic cracking
C. Erosion, caustic cracking, brittle fracture, Clover leafing
D. None of the above
58. When A/E stand by F.O.heater to be used for main engine
A. Sudden opening F.O. inlet valve pressurized and damage the heater
B. F.O. in vapor lock inside heater allow steam
C. F.O. inlet valve causes pressure drop M/E F.O. pressure standby water is not pressurized may cause sudden change in engine /per load/rpm
D. heater leaking.
59. Viscosity of fuel oil used for ME was 145cst, new fuel comes whose viscosity was more than earlier, what u should do
a) Increase temp setting
b) Change setting of viscotherm
c) Do nothing
d) Open steam valve manually more
60. Which of the following can be done to reduce the cold corrosion of Main Engine cylinder liners using high sulphur fuel oil
A. Increasing cylinder oil feed rate
B. Using high TBN cylinder oil
C. Increasing scavenge air temperature
D. Decreasing cylinder oil feed rate
61. When m/e is running in emergency condition which of the alarms can't be bypassed
1. LO low pressure
2. Jacket water high temp
3. Piston cooling water high temp
4. All the above
62. Which of the following will be required to be done in order to reduce sulphur corrosion of main Engine Components?
A. Increasing the atomization pressure of fuel injectors
B. Fitting exhaust valves with valve rotators
C. Running engine at or near normal sea load
D. Decreasing the F.O. purifier feed rate , running two purifier in series one acting as purifier and other as clarifier
Answer-A,B,C and D
63. Where boiler point temp high?
c) Primary steam drum
d) Secondary steam drum
64. Sudden stop of diesel engine (multiple choices)
A. air in system
B. water in system
C. air filter chocked
D. water in air filter
Answer-A,B and C
65. Mixed lubrication consist of
1. Mix two lubes oil
2. Contimanitiön of hydrodynamic lube oil.
3. Mixed grease and oil
66. The muffling of exhaust gas noise in 4 stroke auxiliary engines in achieved by
(a) Allowing the gas to expand.
(b) Change the direction of their flow.
(c) Cool the gas with injected water. (d) Cool the gas with scavenge air.
Answer-A and B
67. An auxiliary engine turbo-charger makes strange noises when the load changes. The engine parameters however are absolutely fine. An external examination of turbocharger parameters as stated in the manual also reveals nothing. Would you
(a) Continue to run the engine and wait for some time
(b) Stop the engine for a while and make some checks
(c) Reduce the load of the engine
(d) Run it on steady load to make some checks.
68. To avoid the engine running too long on critical speed during start up it is necessary to
(a) Start at speeds above critical speed.
(b) Start at speeds just below critical speed and quickly move across the critical speed.
(c) Start at maximum speed and quickly bring down to just above critical speed.
(d) Eliminate totally the hazards of critical speed by ignoring it.
69. Supercharging an existing medium speed naturally aspirated engine will
(a) Reduce weight of the engine.
(b) Reduce bulk of the engine.
(c) Increase existing power.
(d) Increase piston speed.
(e) Reduce fuel consumption.
Answer-C and E
71. When using low sulfur fuel oil for Emission Control Areas (ECA???S), ideally the TBN of the cylinder oil used should be
A. Lower than normal
B. Higher than normal
C. Same as normal
D. Same as normal if the feed is kept higher
72. Which of the following functions is done by a cam operating an exhaust valve?
A. It governs the timing of opening and closing of the valve.
B. It governs the speed at which the valve operates
C. It governs the amount of opening of the valve
D. All of the above
73. In the latest concept of Variable Geometry Turbocharging, _______angle can be varied to match the turbocharger at varying engine loads
A. Compressor vane
B. Turbine blade
C. Nozzle ring blade
D. Diffuser ring blade
Answer-C74. The primary function of a flame safeguard system, as used on an automatically fired auxiliary boiler, is to prevent
A. accidental dry firing and overpressure
B. uncontrolled fires in the furnace
C. explosions in the boiler furnace
D. explosions in the boiler furnace
75. Directional intake ports in diesel engines are used to
A. reduce air charge turbulence
B. induce air swirl
C. deflect hot combustion gas away from the valves
D. oppose the effects of piston induced squish
76. Why does a chain stretch in service?
A. Due to plastic elongation
B. Due to high temperature expansion
C. Due to wear on rollers and bushes
D. Due to the phenomenon of creep
77. Which of the following methods is normally used to lubricate bearings in a small high-speed diesel engine?
A. Splash lubrication
B. Pressure lubrication
C. Sight feed lubricators
D. Mechanical lubricators
78. External fouling of boiler tubes can lead to:
A. Greater steam generation
B. Tube corrosion
C. Tube Erosion
D. Protection of tube against corrosion
79. What is the purpose of the inlet grid provided within the exhaust gas casing in the gas flow path, prior entry to turbocharger ?
A. To filter out any unburned carbon
B. To absorb and dampen the pressure fluctuation
C. To reduce noise in the constant pressure exhaust piping
D. To prevent any broken piston rings finding their way to turbine
80. The main function of tie rods in the construction of large, low speed diesel engines is to
A. stiffen the bedplate in way of the main bearings to increase the engine's longitudinal strength
B. accept most of the tensile loading that results from the firing forces developed during operation
C. mount the engine frame securely to the hull to prevent shaft coupling misalignment
D. connect the crosshead solidly to the piston rod
81. The fall in speed that occurs in a diesel engine equipped with governor, on increase of load is called:
B. Speed drop
C. Speed droop
D. Speed offset
82. Which of the following factors governs the lower limit of thrust bearing clearance?
A. To allow some oil leakage to prevent overheating
B. Reduction of oil viscosity
C. Alignment of crankshaft
D. To allow the thrust pads to tilt and generate the oil wedge
83. Which of the following can result in cracking of piston crown?
A. Deposits in cooling spaces
B. Impingement of fuel due to faulty injection
C. Insufficient piston cooling oil flow
D. All of the above
84. The boiler water alkalinity in a coil-type auxiliary boiler should be maintained at the pH recommended by the boiler manufacturer to
A. precipitate silica from solution
B. reduce corrosion in the heating coil
C. prevent clogging and erosion in the coil
D. maintain zero water hardness
85. What does the NLGI number of a grease indicate?
A. The oxidation resistance of the grease
B. The consistency of the grease i.e how fluid or non fluid
C. Demulsibility of the grease
D. The shelf life of the grease
86. Which of the following layers of a thin shell bearing gives it its fatigue strength?
A. The overlay
B. The interlay
C. The backing
D. The barrier layer
87. Which of the bearings listed is most widely used for main and connecting rod bearings of modern diesel engines?
B. Poured babbitt, self-aligning
C. Split roller
D. Precision insert
88. Which of the following statements is false?
A. The fuel oil sulfur level is one of the important criteria for choice of TBN level of cylinder oil.
B. The use of anti-polishing rings or flame rings increases the consumption of cylinder oil
C. Excessive cylinder oil feed can lead to harmful deposits in piston top land area
D. None of the above
89. When preparing to light off a cold boiler equipped with a return flow fuel oil system, the recirculating valve directs the flow of oil
A. directly to the fuel oil heater inlet for further warm-up
B. back to the fuel oil settler for further filtration
C. back to the suction side of the service pump
D. directly to the deep tanks
90. Prompt correction of speed of diesel engines driving alternators, without having massive fluctuations is ensured by incorporating:
A. Load limiting devices
B. Load sharing devices
C. Load sensing devices
D. Load shedding devices
91. In a uniflow scavenged marine 2-stroke diesel engine, the scavenge ports in a cylinder liner are machined
A. Only for a part of the circumference, at an angle almost tangential to the circumference of the liner
B. All around the circumference at right angles to the circumference of the liner
C. only for a part of the circumference, at right angles to the circumference of the liner
D. All around the circumference at an angle almost tangential to the circumference of the liner
92. If the tappet clearance between the rocker arm tappet and exhaust valve stem is excessive then:
A. The valve will open early and close later
B. The valve will open later and close early
C. The valve will open and close later
D. The valve will open and close early
93. In order to reduce thermal loading on the upper part of the liner and increase the effectiveness of cylinder lubrication, modern 2-stroke marine diesel engines are designed to have:
A. Cermet coated piston rings, bore cooled liners and uniflow scavenging
B. High top land of piston crown and deeper cylinder cover with top land of crown extending into cylinder cover at TDC
C. Low top land of the piston crown with bore cooled cylinder liner
D. Bore cooled cylinder liner and bore cooled piston crown with toroidal shape combustion chamber
94. Which of the following conditions can lead to reduced power developed by a main engine?
A. High scavenge air temperature
B. Choked air suction filter of a turbocharger
C. Blow past in one or more units
D. All of the above.
95. Which of the following types of diagrams would give an indication of effectiveness of exhaust and scavenge processes?
A. Power card
B. Draw card
C. Light spring diagram
D. All of the above.
96. The arrangement used to protect overheating of the superheaters under fluctuating loads is called
C. Steam dumping valve
D. Feed heater
97. Piston rod stuffing box scraper rings butt clearances should:
A. Not to be allowed to fall below 50% of original clearance
B. Not to be allowed to increase above 50% of original clearance
C. Not to be allowed to fall below manufacturer recommended value
D. Not to be allowed to increase above manufacturer recommended value
98. In a 2-stroke engine a ________________ separates the under piston space from the crankcase.
D. Scavenge space
99. Fusible plugs are installed in fire-tube boilers to
A. provide a means of draining the boiler
B. warn the engineer of low water level
C. cool the crown sheet at high firing rates
D. open the burners' electrical firing circuits
100. Which of the following gauges are generally used to evaluate main bearing clearances?
A. Poker gauge
B. Feeler gauge
C. Telescopic feeler gauge
D. Dial gauge
Answer-C101. In a coil-type auxiliary water-tube circulation boiler
A. unevaporated feedwater collects in the bottom of the flash chamber
B. all generated steam is recirculated through heating coils in the boiler
C. heated water flashes to steam in the boiler heating coils
D. response to steam demand is slower than in a fire-tube boiler
102. For a continuous operation diesel engine, a duplex filter unit would be the best arrangement because
A. changing filter elements would not interrupt engine operation
B. filtering occurs twice in each pass of oil through the system
C. clogging will not occur
D. dropping pressure is half of that through a single filter unit
103. As per regulations, within how many hours before each departure, satisfactory working of the steering gear must be checked?
D. None of the above
104. Modern 4-stroke medium speed, marine diesel engine exhaust valve spindles are rotated by providing
A. Nozzle rings
B. Tappet clearance
C. Spinners or vanes
105. The purpose of economizer is to:
A. Decrease the capacity and size of the auxiliary boiler
B. Cooling down the exhaust gases in order to reduce NOx emission
C. Allowing Sox to react at low temperatures with water to form acids thus reducing Sox emission
D. Increasing the overall efficiency of the main propulsion plant
106. Microbiological growths in marine fuel are a common occurrence that can be
A. extremely detrimental to equipment and operating processes
B. prevented by maintaining proper storage temperatures
C. removed from emulsified fuel oil during the centrifuging processes
D. All of the above are correct.
107. The function of the tie rods is to:
A. Keep the engine components under tension at all the times
B. Just secure the engine parts together
C. Act as holding down bolts for the bedplate and keeps all the engine components together
D. Keep engine components under high compression, so that tensile stresses acting during firing stroke do not exceed this pre-compression to avoid fatigue failure
108. Which of the following types of crankshafts is much lighter at similar power requirements?
A. Fully built type
B. Semi built, all welded type
C. Semi built type
D. Solid forged type
109. After an engine has been started using a Bendix drive unit, the drive gear, or pinion disengages from the flywheel due to
A. the action of a spring
B. rotation of the starting cam
C. the higher rotating speed of the flywheel
D. accumulator pressure
110. Fuels as produced in a refinery are generally sterile, however, contamination can occur as fuels are
A. stored at the refinery
B. stored on the vessel
C. transported to the distribution sites
D. All of the above are correct.
111. Which of the following statements is false?
A. Excessive cylinder liner lubrication can aggravate scuffing.
B. Use of anti polishing ring reduces scuffing.
C. Deep honing of liner fails to give an ideal liner surface.
D. None of the above
112. In a fully built or semi built type crankshaft, how can any slippage at shrink fit be identified?
A. By inspecting the locking arrangement provided
B. By checking the dowel provided.
C. By checking the witness mark provided for reference .
D. By checking the performance of the engine
113. Which of the following is one of the major advantages of resin choking over cast iron choking, in holding down arrangements of modern diesel engines?
A. Better vibration damping properties.
B. Better compressive strength
C. 100% contact, no need for surface preparation
D. None of the above
114. In a 2-stroke crosshead type of engine, the side thrust generated due to rolling and connecting rod and fore-aft thrust due to pitching motion of the ship is taken care of by the:
A. Piston and the liner
B. Connecting rod and the piston rod
C. Crosshead shoes and guides
D. Crankpin and thrust bearing
115. In a VIT equipped jerk type fuel pump:
A. Raising the barrel delays beginning of injection
B. Lowering the barrel delays beginning of injection
C. Raising the barrel delays end of injection
D. Lowering the barrel delays end of injection
116. The over speeding of the diesel engine driving an electric generator could cause
A. low voltage trip to trip
B. reverse power trip to trip
C. damage to windings
D. excessive exhaust temperatures
117. In a large, slow-speed, main propulsion diesel engine, which of the parts listed is under tension when the engine is running?
A. Bed plate
D. Tie rod
118. A diffuser is provided at the end of a mechanical atomizer in boiler onboard
A. To prevent blow back of the flame
B. To mix the air and fuel properly
C. To prevent blow out of the flame
D. To eject the excess fumes from the atomizer
Answer-A and B
119. Steam stop valve is eased of its seat during boiler start up from cold
A. To allow thermal expansion of parts
B. To allow steam flow during start up
C. To prevent water hammer
D. All of the above
120. Which of the following statements about the design of D- type boilers, is false ?
A. The heavier water in top drum flows back to the bottom drum through the down- comers outside the furnace
B. Inside the furnace the water is heated up in the risers
C. The upper drum is the steam/water drum and the lower one is the water drum.
D. The feed water is pumped into the lower drum
121. Presence of catalytic fines in fuel oil is significant to engineers on board because
A. Catalytic fines tend to impair proper operation of purifiers
B. Catalytic fines lead to abrasive wear in liners, piston rings and fuel injection equipment
C. Catalytic fines necessitate increase in injection temperature
D. Catalytic fines necessitate increase in storage temperature
122. With reference to the data logger for a refrigerate sys. Which of the parameters should be noted?
A. Sea water temp, pressure
B. Condenser temp
C. Refrigerant leakage
D. Evaporator temp.
Answer-A,B and D
123. Which of the following factors affect penetration of fuel droplets during injection?
A. Quality of atomization
B. Injection temperature
C. Scavenge air pressure
D. All of the above.
124. Lube oil pumps taking suction from the sump of most small marine engines are usually
A. of the diaphragm type
B. of the centrifugal type
C. positive displacement type
D. independently driven by electric motors
125. Telescopic pipes to the piston of a large slow-speed main propulsion diesel engine are designed to prevent
A. excessive crankcase pressure
B. excessive lube oil temperature
C. contamination of the lube oil by water
D. contamination of the cooling water by lube oil
126. Excessive axial thickness of a piston ring can lead to ____________________
A. Scraping off of oil from liner surface
B. Increased wear
C. Twisting in the groove
D. Difficulty in formation of oil wedge
127. Which of the following is an adhesive?? type wear of a cylinder liner?
A. Clover- leafing
128. Cylinder heads of marine diesel engines are provided with _________ to relieve any excessive pressure within the combustion chamber
A. Safety valves
B. Indicator cocks
C. Relief valves
D. Bursting discs
129. Working of a pulse pressure turbocharger depends upon the ___________ that can be safely created in the exhaust system.
A. Enthalpy drop
B. Pressure difference
C. Turbocharger rpm
D. Pressure pulses
130. The maximum elongation of timing chains in service is limited to ___________ of original chain length.
131. Duplication of power units, fittings and pipings where each unit is capable of providing 100% steering power, and automatic isolation of one unit in the event of a leakage(single failure) in that unit would constitute 100% redundancy for the steering gear system. Such system is mandatory on ____________
A. All tankers
B. Tankers above 10000 GT
C. Tankers above 100000 Dwt
D. All ships above
132. Routine cleaning of air side of air cooler of main engine is done by:
A. Circulating fresh water
B. Circulating cold chemical solution
C. Circulating warm chemical solution
D. Circulating hot water
133. What prevents rotation and fretting between a thin shell bearing and its housing?
A. Location tangs or pegs
B. The nip or crush of the bearing
C. A special kind of adhesive
D. Any of the above
134. Microbial degradation of main engine sump oils can lead to:
A. Increased clogging of lube oil filters
B. Corrosive attack on journals and bearings
C. Formation of stable emulsions
D. All of the above.
135. In case of constant pressure turbo charging, the exhaust of the cylinders goes into :
A. Small diameter exhaust pipes with exhaust grouping
B. Exhaust compensators
D. Large diameter pipes
136. Which of the following is a limiting factor in cylinder liner cooling?
A. Maximum combustion temperature
B. Minimum liner temperature
C. Exhaust temperature
D. Dew point for formation of sulfuric acid
137. Which of the following is not a consequence of over lubrication of a cylinder liner?
A. Deposits in piston top land which can not only consume lube oil but always lead to increased abrasive wear
.B. Sticking and jamming of piston rings due to increased deposits.
C. Unburnt lube oil in scavenge spaces posing increased risk of scavenge fire .
D. Increased corrosive wear
138. Variable geometry turbocharging is the preferred choice over conventional turbochargers because :
A. T/C efficiency is very high at high engine loads
B. T/C has good starting characteristics while efficiency at full loads is slightly compromised
C. T/C efficiency is optimized for different engine loads by changing nozzle ring geometry
D. T/C is much cheaper and simple to manufacture and is virtually maintenance free
139. As a thumb rule, ovality in crankpins of medium speed engines should not exceed _____________ of bearing clearance.
140. In a naturally aspirated diesel engine, the volume of air intake is directly related to engine
A. compression ratio
B. valve size
C. fuel pressure
D. cylinder clearance volume