Marine Engineers Q&A: Diesel Engines, Turbochargers, Fuels, and Oils PDF

Marine Engineers and Superintendents Technical Support http://MarEngine.com 50 Questions and Answers For Marine Engineers Issue 1 Diesel Engine, Turbocharger, Fuel, Oil Operation & Service Manuals, and Spare Parts Catalogs http://engine.od.ua Marine spare parts and equipment http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 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 Answer-D 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 Answer-A 3. 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 does not 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 Answer-A 4. 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 its density and also to keep the peak temperature and exhaust gas temperature within limits Answer-B 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 Answer-A 6. 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 inserts which 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 Answer-D Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 1 Marine Engineers and Superintendents Technical Support http://MarEngine.com 7. 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. Answer-B 8. Modern marine turbochargers use a ___________ type of compressor A. Radial flow B. Axial flow C. Mixed flow D. Turbulent flow Answer-A 9. 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 Answer-D 10. 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 Answer-C 11. The lube oil pump used in a diesel engine is a A. volute pump B. centrifugal pump C. diaphragm pump D. gear pump Answer-D 12. The coating which is provided on the valve stem of exhaust valves of modern marine diesel engines is of: A. Nickel B. Stellite C. Chromium D. Nimonic Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 2 Marine Engineers and Superintendents Technical Support http://MarEngine.com 13. 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. Answer-D 14. 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 Answer-B 15. 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 Answer-C 16. 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 Answer-C 17. 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 Answer-C 18. 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 Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 3 Marine Engineers and Superintendents Technical Support http://MarEngine.com 19. 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 Answer-B 20. 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 Answer-A 21. 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 Answer-C 22. 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 Answer-C 23. 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 Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 4 Marine Engineers and Superintendents Technical Support http://MarEngine.com 24. Which of these fuel oil impurities can cause maximum abrasive damage? A. Water B. Ash C. Catalytic fines D. Sodium Answer-C 25. 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. A. monel B. chromium C. inconel D. cermet Answer-C 26. Irregular circumferential wear of liner due to diminishing neutralizing capacity of cylinder oil away from lubricating holes is known as: A. Micro seizure B. Scuffing C. Scoring D. Clover leafing Answer-D 27. 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 Answer-C 28. 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 Answer-B 29. To check the setting of the over speed trip on a diesel powered generator, you would use a A. tachometer B. torsion meter C. dynamometer D. pony brake Answer-A Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 5 Marine Engineers and Superintendents Technical Support http://MarEngine.com 30. Which of the following specifications/qualities of cylinder oils counter corrosive wear? A. Viscosity B. TBN C. Detergency D. Specific gravity Answer-B 31. 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 Answer-A 32. 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, reheated, and returns to the sump Answer-C 33. Types of corrosion in fresh water of Diesel Engines A. Stress B. Hot corrosion C. Bimetallic D. Selective phase corrosion Answer-D 34. 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 Answer-A 35. 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. Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 6 Marine Engineers and Superintendents Technical Support http://MarEngine.com 36. 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 Answer-C 37. 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 Answer-B 38. When main engine is running in emergency condition which of the alarms can't be bypassed A. LO low pressure B. Jacket water high temp C. Piston cooling water high temp D. All the above Answer-D 39. 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 purifiers in series one acting as purifier and other as clarifier Answer-A, B, C and D 40. 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 41. Mixed lubrication consist of A. Mix two lubes oil B. Contamination of hydrodynamic lube oil. C. Mixed grease and oil Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 7 Marine Engineers and Superintendents Technical Support http://MarEngine.com 42. 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 scavenges air. Answer-A and B 43. An auxiliary engine turbocharger 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. Answer-B 44. 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. Answer-B 45. 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 46. 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 Answer-A 47. 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 Answer-D Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 8 Marine Engineers and Superintendents Technical Support http://MarEngine.com 48. 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-C 49. 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 Answer-B 50. 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 Answer-C These questions mainly were taken from the website http://www.class4exam.com. Thanks for web site administration and marine engineers who shared your experience. Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 9 Marine Engineers and Superintendents Technical Support http://MarEngine.com 50 Questions and Answers For Marine Engineers Issue 2 Diesel Engine, Turbocharger, Fuel, Oil Operation & Service Manuals, and Spare Parts Catalogs http://engine.od.ua Marine spare parts and equipment http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 1. 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 Answer-B 2. 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 Answer-A 3. 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 Answer-B 4. The fall in speed that occurs in a diesel engine equipped with governor, on increase of load is called: A. Offset B. Speed drop C. Speed droop D. Speed offset Answer-C 4. 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 Answer-D 5. 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 Answer-D 6. What does the NLGI number of 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 Answer-B Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 7. 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 Answer-A 8. Which of the bearings listed is most widely used for main and connecting rod bearings of modern diesel engines? A. Steel-lined B. Poured babbitt, self-aligning C. Split roller D. Precision insert Answer-D 9. 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 Answer-B 10. 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 Answer-C 11. 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 Answer-D 13. 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 Answer-B Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 12. 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. Cermets 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 Answer-B 13. 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. Answer-D 14. 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. Answer- C 15. As a thumb rule, ovality in crankpins of medium speed engines should not exceed ______of bearing clearance. A. 10% B. 15% C. 25% D. 30% Answer- pls check and inform me [email protected] 16. 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 Answer-B 17. 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 Answer-C Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 18. In a 2-stroke engine a _________ separates the under piston space from the crankcase. A. A-frame B. Crosshead C. Diaphragm D. Scavenge space Answer-C 19. 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-C 20. 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 Answer-A 21. As per regulations, within how many hours before each departure, satisfactory working of the steering gear must be checked? A. 2 B. 12 C. 24 D. None of the above Answer-B 22. 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 D. Rotocaps Answer-D 23. 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. Answer-A Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 24. 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 Answer-D 25. 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 Answer-B 26. 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 Answer-C 27. 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. Answer-D 28. 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 Answer- D 29. 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 Answer-C Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 30. 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 Answer-C 31. 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 Answer-C 32. 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 Answer-A 33. 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 Answer-C 34. 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 B. Column C. Entablature D. Tie rod Answer-D 35. 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 Answer-B Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 36. 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. Answer-D 37. 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 Answer-C 38. 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 Answer-C 39. 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 Answer-D 40. Which of the following is an adhesive type wear of a cylinder liner? A. Clover- leafing B. Scoring C. Scuffing D. Ovality Answer-B 41. 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 Answer-C Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 42. 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 Answer-D 43. The maximum elongation of timing chains in service is limited to ___________ of original chain length. A. 2% B. 1% C. 5% D. 3% Answer-A 44. 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 Answer-C 45. 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 Answer-B 46. 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. Answer-D 47. 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 C. Nozzles D. Large diameter pipes Answer-B Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 48. 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 Answer-D 49. 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 Answer-A 50. 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 Answer-C These questions mainly were taken from the website http://www.class4exam.com. Thanks for web site administration and marine engineers who shared your experience. Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 50 Questions and Answers For Marine Engineers Issue 3 Diesel Engine, Turbocharger, Fuel, Oil Operation & Service Manuals, and Spare Parts Catalogs http://engine.od.ua Marine spare parts and equipment http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 1. An auxiliary engine turbo-charged 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 do 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. (NOTE-this type of Question also asked in Exam just to check your way of thinking) 2. What type of lubricating oils is generally used in auxiliary engines? A. Detergent B. Alkaline C. Synthetic D. It is not important. Answer-A 3. An emergency diesel generator cooling system is equipped with an automotive type thermostat. If the thermostat bellows loses its charge, the thermostat will __________. A. open, and the coolant temperature will increase B. open, and the coolant temperature will decrease C. close, and the engine coolant temperature will increase D. close, and the coolant temperature will decrease Answer-C 4. 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 Answer-B (Because bottom end bearing bolts are max amount of fatigue stress) 5. A D/E with full speed rpm of 1000 drives a propeller at 300 r.p.m...what is speed reduction ration? A. 0.3 to 1 B. 3.33 to 1 C. 33 to 1 hde D. 300 to 1 Answer-B Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 6. Labyrinth seal fitted onthe back surface of a compressor wheel of a turbocharger A. prevents bearing lube oil contamination B. prevents bearing lube oil being sucked in to air stream C. helps to keep the shaft cool by controlled leakage of air D. none of the above Answer-May be D but Not Sure(Because Labyrinth seals or glands are fitted to the shaft and casing to prevent the leakage of exhaust gas into the turbine end bearing, or to prevent oil being drawn into the compressor. To assist in the sealing effect, air from the compressor volute casing is led into a space within the gland. A vent to atmosphere at the end of the labyrinth gives a guide to the efficiency of the turbine end gland. Discoloring of the oil on a rotor fitted with a roller bearing will also indicate a failure in the turbine end gland) 7. In the _____ type of t/c 2/s diesel engine is _____ to start. A. constant, easier B. constant, difficult C. pulse, difficult D. none Answer-B 8. The speed of the turbocharger for a four-stroke/cycle diesel engine driving a generator at constant speed depends on the A. engine speed B. kilowatt load C. fuel injection pressure D. air intake manifold temperature Answer-A (Because impulse turbine is used but it may be B also because for Four Stroke the speed will be almost Constant) 9. 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 its density and also to keep the peak temperature and exhaust gas temperature within limits Answer-C 10. The speed of the turbocharger for a four-stroke/cycle diesel engine driving a generator at constant speed depends on the A. engine speed B. kilowatt load C. fuel injection pressure D. air intake manifold temperature Answer-A (Because impulse turbine is used but it may be B also because for Four Stroke the speed will be almost Constant) Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 11. 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 its density and also to keep the peak temperature and exhaust gas temperature within limits Answer-C 12. 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 is density and also to keep the peak temperature and exhaust gas temperature within limits Answer-C 13. Most T/C have ________ flow type of Compressor and ________ flow type of Rotor A. Centrifugal Radial , Impeller axial B. Centrifugal axial, Impeller radial C. Centrifugal mixed, Reaction Radial D. Rotary axial, Reaction Radial Answer-B ??? (doubt) 14. Modern marine turbochargers use a ___________ type of compressor A. Radial flow B. Axial flow C. Mixed flow D. Turbulent flow Answer-B 15. 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 Answer-B Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 16. With full load on the main engine, the RPM for the turbocharger is too low. What may cause this? A. The diffuser ring is damaged. B. Exhaust temperatures on the main engine are too high. C. Dirty nozzle ring. D. The lubricating oil pump is malfunctioning. Answer- C ? (Not Sure) 17. For a main engine fuel system which has a 5 micron filter ,a super decanter is usually fitted ___ A. before the purifier B. after the purifier C. after the 5 micron filter to ME D. before the horizontal clarifier Answer-A 18. The timing of the engine is delayed. The exhaust temperatures are high. How would you expect this to affect the turbocharger? A. Decreased turbocharger revolutions. B. Surging of the turbocharger. C. Increased turbocharger revolutions D. Higher air and gas temperature after turbocharger. Answer-B (Because if after ignition is occurring there will be more pr when the piston uncovers the ports hence more back pr where as the exhaust gases are not turning the turbine (low exhaust) hence surging) 19. What is the meaning of the term "valve clearance"? A. The clearance between the rocker arm and valve pushrod. B. The clearance between valve spindle disc and seat. C. The clearance between the rocker arm and camshaft pushrod. D. The clearance between the rocker arm and valve pushrod in either warm or cold state. Answer-A 20. 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 Answer-B 21. If water contamination occurs in the crankcase oil of an auxiliary engine the oil viscosity will: A. Increase. B. Nothing happens C. Stay at the same. D. Decrease. Answer-A (Because Emulsification Increase the viscosity) Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 21. Proper lubrication of the main bearings is more easily obtained in a single acting four- stroke/cycle diesel engine than a single acting two-stroke/cycle diesel engine because A. bearing pressure in a four-stroke/cycle single acting diesel engine is continually reversed B. bearing pressure in a two-stroke/cycle single acting diesel engine is continually reversed C. the maximum bearing pressure is higher in a single acting two-stroke/cycle diesel engine D. two-stroke/cycle diesel engines require more complicated lubrication piping Answer-A 22. A unit type fuel injector is used on a diesel engine to A. meter the fuel B. produce the proper fuel oil pressure C. atomize the fuel D. all of the above Answer-D 23. The air spring pressure to prevent ME exhaust valve hammer is in the region of____ A. 2 kg B. 7kg C. 12 kg D. 14 kg Answer-B 24. When the prime movers of two paralleled generators, equipped with mechanical- hydraulic governors, are operating within their designed range, the unit with the least amount of speed drop will _____ A. pick up more of any increase in load B. pick up less of any increase in load C. share an equal amount of any increase in load D. drop an equal amount of any decrease in load Answer-A 25. In case of failure of control air supply, some valves continue locked in the position they were at the time of failure. They are said to be______ A. Fail-safe B. Fail –proof C. Fail-set D. Fail -blocked Answer-C 26. Too high Calculated Carbon Aromaticity index (CCAI) of fuel oil indicates: A. Reduced ignition delay B. Increased ignition delay C. Reduced chances of knocking D. None Answer-B Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 27. A high pressure differential in a main engine fuel oil filter onboard can be best reduced by A. Back flushing the filter manually B. Stopping the main engine to change the filter element C. Changing over to stand by filter if provided D. None of the above Answer-A (Because by changing on to the other filter u r not reducing the differential pr in that filter element) 28. The theoretical minimum compression ratio necessary to ensure compression ignition in a direct injection diesel engine is __________ A. 10:01 B. 12:01 C. 08:01 D. all of the above Answer-B 29. We have a problem with vibration in the turbocharger. What might be the cause? A. Dirty air inlet filter. B. The turbine rotor is not balanced C. The lubricating oil needs to be changed. D. Worn out turbocharger bearings. Answer-B and D (B Because if any other turbine blade has been worn out or something turbine will not be balanced. D Because naturally if the roller or ball bearing has been worn it in either turbine or compress side respectively vibrations would be produced) 30. Generator over speed trip what will u check A. governor is not responding (ANS) B. fuel system C. moving parts (crank shaft) D. all of the above Answer-A 31. With full load on the main engine, the turbocharger tachometer reads: Too low RPM. Why? A Damaged connection between pick- up and tachometer unit B Pick up is not connected to turbocharger. C Turbocharger need to be cleaned/ overhauled. D Pick up for tachometer is wrongly adjusted. Answer-D 32. To reduce the weight of the reciprocating parts pistons of high speed engines are made considerably shorter. This results in__________ A. less piston slap and quitter running B. increased crankshaft bearing wear C. slightly greater piston wear D. decreased side pressure Answer-D Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 33. The effect of excessive tappet clearance in 4 stroke auxiliary engine _____ A. Increased engine efficiency as expansion can take place for a longer duration and less energy wasted with the exhaust gases B. Valve hammering, change in timing of exhaust with more side thurst causing greater wear between stem and bush C. Loss in compression, poor combustion, improper mixing of fuel & air and gas gas leakage due to improper closing of valve D. Turbocharger surging, loss of rotation of valve spindle and high exhaust temperatures Answer-B 34. Sequential starting of machineries after black out in engine room is necessary A. To prevent overload of Generators B. To quickly restore the failed power supply in order C. To prevent damage to machinery this has been switched off D. All of the above Answer-A (because sequential starting is to prevent generator from overloading it has nothing to do with damage with machinery. it just starts the machinery in sequence which are needed first... preference... else because if all r started once all the load will come on generator and it will get trip... as starting current is high for motors) 35. Kinetic energy is converted into pressure energy in a turbocharger compressor by: A. Combined diffuser and nozzle ring B. Nozzle ring only C. Combined diffuser and volute casing D. Volute casing only Answer-C 36. 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 Answer-C 37. 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. Answer-B 38. What long term effect will excessively high temperature have on lubricating oil quality? A. Cause oxidation which reduces viscosity. B. Evaporates the oil giving high consumption. C. The oil flashpoint will be changed. D. Cause oxidation which increase viscosity. Answer-D Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 39. You have checked the oil viscosity in an auxiliary engine with the viscosity test kit. The result shows that the viscosity is high. What will you do? A. Decrease the cooling water temperature for the oil. B. Clean the system and change the oil C. Increase the cooling water temperature for the oil. D. Increase the lub oil pressure. Answer-B 40. Valves used in diesel engine fuel oil pressure piping are to be A. installed to close against flow B. solenoid released upon the failure of engine lubrication C. either of the gate or globe valve type D. forge constructed under the approval of the Marine Inspector Answer-A 41. A normal manometer reading of turbocharger air suction filter and normal speed of the turbocharger but reduced scavenge air pressure may be due to: A. Fouling of the nozzle ring B. Fouling of diffuser or compressor wheel C. Fouling of the turbine D. Cold climate Answer-B 42. Following method is sometimes used in constant pressure turbochargers of a 4-stroke diesel alternators during starting and rapid acceleration: A. Auxiliary electrical blowers assisting turbochargers during starting B. Auxiliary shaft driven blowers assisting turbochargers during starting C. Auxiliary air drive for turbocharger acceleration during starting D. Variable geometry turbocharging Answer-C 43. The difference between rotocap and spinners for rotating exhaust valve spindle is that: A. Rotocaps rotate the valves while closing, while spinners rotate them while opening B. Rotocaps rotate the valves while opening, while spinners rotate them while closing C. Rotocaps rotate the valves while opening, while spinners rotate the valve for the entire duration until valve is seated Answer-C 44. The difference between water washing and dry cleaning the TC turbine is A. there is no difference one is wet, the other is dry B. wet washing requires reduced load C. dry cleaning requires reduced load d) none of the above Answer-B Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 45. 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 Answer-C 46. During prolonged astern maneuvering of the relative expansion between any of the turbine its casing is likely to increase for an alarming level you should (multi choice) in photo no3 in download A) Inform the bridge that no further maneuvering is possible as the turbine are likely to be damaged B) Reduce the vacuum further to control the relative expansion C) Keep maneuvering irrespective of damage to the turbines D) Request the bridge to try to reduce number of astern movements Answer-D 47. 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 its density and also to keep the peak temperature and exhaust gas temperature within limits Answer-C 48. 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 Answer-B 49. Clearance volume scavenging in a turbocharged, four-stroke/cycle diesel engine is accomplished A. During the valve overlap period B. With only the exhaust valve open C. At a pressure below atmospheric D. Without cooling the cylinders or pistons Answer-A 50. The type of corrosion normally occurring in cooling Fresh Water systems of Marine Diesel Engines is A. Stress corrosion B. Hot corrosion C. Bimetallic corrosion D. Selective Phase corrosion Answer-D Operation & Service Manuals, and Spare Parts Catalogs - http://engine.od.ua Marine spare parts and equipment - http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 50 Questions and Answers For Marine Engineers Issue 4 Auxiliary Equipment Operation & Service Manuals, and Spare Parts Catalogs http://engine.od.ua Marine spare parts and equipment http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 1. 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 Answer-A 2. 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 Answer-C 3. 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 Answer-D 4. 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 Answer-B 5. 3-ballast pump is being used to deballast a fore peak tank which is full. It is seen that suction pressure is positive and discharge pressure is very low compared to rated discharge head. It indicates that: A. Pump is not operating satisfactorily and pumping capacity is too low B. Pump is not operating satisfactorily and pumping capacity is higher than rated, throttling of discharge valve is required C. Pumping capacity is not affected by suction and discharge pressures D. Pump is operating normally Answer-B 6. In a reciprocating pump the direction of flow depends upon: A. Direction of rotation of the pump B. Position & fixing of suction and discharge valves C. High pressure to low pressure D. Whether pump is single acting or double acting Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 1 Marine Engineers and Superintendents Technical Support http://MarEngine.com 7. If the direction of rotation of a gear pump is reversed due to change in-phase sequence, what happens when the pump is started? A. Direction of flow remains the same B. The pump will get damaged due to overpressure on suction side C. Pump relief valve will be lifted D. The direction of flow will be reversed Answer-D 8. Which of the following cause cavitations a. Low discharge pressure b. Throttling the suction valve c. Low water level in the wet well d. High discharge pressure Answer-C 9. 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 Answer-D 10. 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 Answer-A 11. 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 Answer-C 12. 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 Answer-A Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 2 Marine Engineers and Superintendents Technical Support http://MarEngine.com 13. 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. Answer-A 14. Shaft tunnel requires A. drain B. escape trunk C. water tight door D. all the above Answer-D 15. 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 Answer-D 16. 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 insoluble will lead to increase in viscosity of a lubricant Answer-A 17. 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 Answer-C 18. 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 Answer-D 19. 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 Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 3 Marine Engineers and Superintendents Technical Support http://MarEngine.com 20. Which type of boiler burner has max turn down ratio? A. Pressure set B. Spinning cup C. Spill type D. Y-jet type Answer-D 21. During shutting down the purifier you find that purifier always vibrates heavily for some time and then becomes normal until it finally comes to a stop. What should be done to avoid this situation? A. The purifier bowl should be cleaned before next startup B. The brake should be applied so that the critical speed does not last long C. Complete overhaul of the purifier should be carried out and the bearings need to be renewed D. The bowl should be sent for balancing Answer-B 22. Centrifugal pump will typically give you a low flow rate at a lower pressure, where a piston pump will give you more pressure and higher flow rate. Is the statement correct? A. True B. False C. First Sentence is right. Second one is wrong D. I Don't know Answer-B 23. Sludge pump suction pressure is going full vacuum when u start the pump taking water of double bottom tank suction u hv checked the suction filter n found in clean condition. Taking suction fr fuel oil sludge tank does not happen. Causes of the problem. A. Pump is not working efficiently n reqd. overhauling B. Sludge tank suction valve is leaking C. W.O. tank D.B. tank suction pipeline has a blockage. D. Can you say what the problem is but definitely the pump needs to b opened up for overhaul Answer-C 24. 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 Answer-C 25. Where boiler point temp high? A. Riser B. Superheater C. Primary steam drum D. Secondary steam drum Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 4 Marine Engineers and Superintendents Technical Support http://MarEngine.com 26. 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 Answer-C 27. External fouling of boiler tubes can lead to: A. Greater steam generation B. Tube corrosion C. Tube Erosion D. Protection of tube against corrosion Answer-B 28. Which of the foll wl cause cavitation A. low discharge pressure B. Throttling the suction valve C. Low water level in the wet well D. High discharge pressure Answer-C 29. In reverse osmosis type freshwater generator plants, pretreatment of the feed water is done to: A. Soften the feed water B. Sterilize the feed water C. To facilitate wash through of salt deposits on elements D. Add necessary minerals to the water Answer-C 30. Centrifugal pumps cannot handle air and require priming. But you are aware that centrifugal which on the same principal can handle air very well. Which two properties of air are responsible because of which the centrifugal pumps cannot handle air: A. Fluidity only B. Density only C. Both fluidity and density D. Compressibility Answer-C 31. 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 Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 5 Marine Engineers and Superintendents Technical Support http://MarEngine.com 32. When preparing to light off a cold boiler equipped with a return flow fuel oil system, the recirculation 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 Answer-C 33. The arrangement used to protect overheating of the superheaters under fluctuating loads is called A. De-superheater B. Attemperator C. Steam dumping valve D. Feed heater Answer-B 34. 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 Answer-B 35. By which of the following is the attached vacuum pump of a ballast pump is driven? A. Electrical motor B. Hydraulic motor C. Pump driven clutch D. Pneumatically driven Answer-C 36. Why centrifugal p/p not provided with safety valve while positive displacement p/p is provided? a. c/f p/p shut down head is O b. c/f p/p shut down head is infinity c. c/f p/p is so designed that it can withstand high pressure d. not sure Answer-A 37. When centrifugal pump is overhauled it was found that shaft had developed grooves on it n no spare is available onboard what action can be taken a. Order a new spare b. Assemble the pump without doing anything n wait for the spare to arrive. c. Machine the shaft sleeve on lathe n put back the new packing. d. Leave the pump as it is Answer-C 38. In a coil-type auxiliary water-tube circulation boiler A. unevaporated feed water 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 Answer-A Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 6 Marine Engineers and Superintendents Technical Support http://MarEngine.com 39. 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 Answer-D 40. 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 Multiple Choice Question 41. Salinity of distilled water produced from fresh water generator onboard depends on A. Amount of feed set in fresh water production B. Amount of salt water leaking from condenser if any C. Temperature of the sea water used D. Efficiency of brine ejector from the evaporator shell Answer-A,B & D 42. Ballast pump injection filter was cleaned n the pump was lined up it was found that there was some leakage in the suction filter suction. The pump started n the leakage started. During deblasting it was found that the pump could not take suction fr one of the double bottoms. The cause could be A) Pump was drawing air from outside. B) Pump was drawing air from suction filter C) One of the pipelines on the suction side of the pump might be leaking D) The filter was not cleaned properly. Answer-B 43. Less vacuum in centrifugal pp A leaky discharge vv B loss of gland packing C loss of fluid from suction take place D long suction pipe Answer-B 44. 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 Answer-D Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 7 Marine Engineers and Superintendents Technical Support http://MarEngine.com 45. 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 Answer-D 46. With reference to the data logger for a refrigerate system. 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 47. Tube in air compressors, self compensating for expansion A. Straight line tube B. U tube C. Coil tube D. Floating tube Answer-B 48. Deep well cargo pump are used in A. chemical tanker B. product carrier C. LNG D. all Answer-C 49. After your overhaul a centrifugal pump is not rotating what may be the possible cause: A. Uneven tightening of casing bolts B. Gasket thickness very thin C. More wear ring clearance D. Only a E. a and b F. a and c Answer-E 50. 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 Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 8 Marine Engineers and Superintendents Technical Support http://MarEngine.com 50 Questions and Answers For Marine Engineers Issue 5 Auxiliary Equipment Operation & Service Manuals, and Spare Parts Catalogs http://engine.od.ua Marine spare parts and equipment http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 1. During shutting down the purifier you find that purifier always vibrates heavily for some time and then becomes normal until it finally comes to a stop. What should be done to avoid this situation? A. The purifier bowl should be cleaned before next startup B. The brake should be applied so that the critical speed does not last long C. Complete overhaul of the purifier should be carried out and the bearings need to be renewed D. The bowl should be sent for balancing Answer-B 2. Fixed vane type emergency fire pump priming vacuum pump. After one week fire pump not taking suction. The vacuum pump is engaging, but not developing vacuum in the suction side. What will be the cause? A. Suction filter of the pump clogged. B. Suction filter cover gasket leaks. c) Vacuum pump not overhauled properly. d) Sealing water tank is empty. Answer-Not Sure in between of A and D 3. It is given that engine room bilge pump has suction manifold on which 3 valves are located. One valve for the 3 engine room bilge wells suction, another one for Bilge tank suction and the third one is for sea water suction. It is found that the Bilge pump is unable to take suction from any of the bilge wells, but is able to take suction efficiently from Bilge tank. What is the most probable cause? A. Pump suction filter cover gasket leaking B. Suction filter cover gasket of one of the Bilge wells is leaking C. Bilge well suction pipeline leaking between individual bilge well valves and suction manifold valve D. Bilge pump suction pipeline leaking between the manifold and the pump Answer-C 4. Centrifugal pump will typically give you a low flow rate at a lower pressure, where a piston pump will give you more pressure and higher flow rate. Is the statement correct? A. TRUE B. FALSE C. First Sentence is right. Second one is wrong D. I Don't know Answer-B 5. Sludge pump suction pressure is going full vacuum when u start the pump taking water of double bottom tank suction u hv checked the suction filter n found in clean condition. Taking suction fr fuel oil sludge tank does not happen. Causes of the problem. A) Pump is not working efficiently and required overhauling B) Sludge tank suction valve is leaking C) W.O. tank D.B. tank suction pipeline has a blockage. D) Cannot say what is the problem but definitely the pump needs to be opened up for overhaul Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 1 Marine Engineers and Superintendents Technical Support http://MarEngine.com 6. In reverse osmosis type freshwater generator plants, pretreatment of the feed water is done to: A. Soften the feed water B. Sterilize the feed water C. To facilitate wash through of salt deposits on elements D. Add necessary minerals to the water Answer-C 7. Centrifugal pumps cannot handle air and require priming. But you are aware that centrifugal which on the same principal can handle air very well. Which two properties of air are responsible because of which the centrifugal pumps cannot handle air: A. Fluidity only B. Density only C. Both fluidity and density D. Compressibility Answer-C 8. By which of the following is the attached vacuum pump of a ballast pump is driven? A. Electrical motor B. Hydraulic motor C. Pump driven clutch D. Pneumatically driven Answer-C 9. Why centrifugal p/p not provided with safety valve while positive displacement p/p is provided? A. c/f p/p shut down head is o B. c/f p/p shut down head is infinity C. c/f p/p is so designed that it can withstand high pressure D. not sure Answer-A 10. When centrifugal pump is overhauled it was found that shaft had developed grooves on it n no spare is available onboard what action can be taken A. Order a new spare B. Assemble the pump without doing anything n wait for the spare to arrive. C. Machine the shaft sleeve on lathe n put back the new packing. D. Leave the pump as it is Answer-C Multiple Choice Question 11. Salinity of distilled water produced from fresh water generator onboard depends on A. Amount of feed set in fresh water production B. Amount of salt water leaking from condenser if any C. Temperature of the sea water used D. Efficiency of brine ejector from the evaporator shell Answer-A, B & D Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 2 Marine Engineers and Superintendents Technical Support http://MarEngine.com 12. Ballast pump injection filter was cleaned n the pump was lined up it was found that there was some leakage in the suction filter suction. The pump started n the leakage started. During deblasting it was found that the pump could not take suction fr one of the double bottoms. The cause could be A. Pump was drawing air from outside. B. Pump was drawing air from suction filter C. One of the pipelines on the suction side of the pump might be leaking D. The filter was not cleaned properly. Answer-B 13. Less vacuum in centrifugal pp A. leaky discharge vv B. loss of gland packing C. loss of fluid frm suction take place D. long suction pipe Answer-B 14. Tube in air compressors, self compensating for expansion A. Straight line tube B. U tube C. Coil tube D. Floating tube Answer-B 15. Deep well cargo pump are used in A. chemical tanker B. product carrier C. LNG D. All Answer-C 16. After your overhaul a centrifugal pump is not rotating what may be the possible cause: A. Uneven tightening of casing bolts B. Gasket thickness very thin C. More wear ring clearance D. Only a E. a and b F. a and c Answer-E 17. Fixed vane type emergency fire pump priming vacuum pump. After one week fire pump not taking suction. The vacuum pump is engaging, but not developing vacuum in the suction side. What will be the cause? A. suction filter of the pump clogged. B. suction filter cover gasket leaks. C. vacuum pump not overhauled properly. D. sealing water tank is empty. Answer-Not Sure in between of A and D Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 3 Marine Engineers and Superintendents Technical Support http://MarEngine.com 18. It is given that engine room bilge pump has suction manifold on which 3 valves are located. One valve for the 3 engine room bilge wells suction, another one for Bilge tank suction and the third one is for sea water suction. It is found that the Bilge pump is unable to take suction from any of the bilge wells, but is able to take suction efficiently from Bilge tank. What is the most probable cause? A. Pump suction filter cover gasket leaking B. Suction filter cover gasket of one of the Bilge wells is leaking C. Bilge well suction pipeline leaking between individual bilge well valves and suction manifold valve D. Bilge pump suction pipeline leaking between the manifold and the pump Answer-C 19. Which is true? A. Rotary vane steering gear generally operates at high oil pressure than RAM type B. RT > RV C. RT=RV Answer-B 20. After your overhaul a centrifugal pump is not rotating what may be the possible cause: A. Uneven tightening of casing bolts B. Gasket thickness very thin C. More wear ring clearance D. Only a E. a and b F. a and c Answer-E 21. Fixed vane type emergency fire pump priming vacuum pump. after one week fire pump not taking suction. The vacuum pump is engaging, but not developing vacuum in the suction side. What will be the cause? A. suction filter of the pump clogged. B. suction filter cover gasket leaks. C. vacuum pump not overhauled properly. D. sealing water tank is empty. Answer-Not Sure in between of A and D 22. It is given that engine room bilge pump has suction manifold on which 3 valves are located. One valve for the 3 engine room bilge wells suction, another one for Bilge tank suction and the third one is for sea water suction. It is found that the Bilge pump is unable to take suction from any of the bilge wells, but is able to take suction efficiently from Bilge tank. What is the most probable cause? A. Pump suction filter cover gasket leaking B. Suction filter cover gasket of one of the Bilge wells is leaking C. Bilge well suction pipeline leaking between individual bilge well valves and suction manifold valve D. Bilge pump suction pipeline leaking between the manifold and the pump Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 4 Marine Engineers and Superintendents Technical Support http://MarEngine.com 23. Which of the following statements concerning antifriction bearings installed on pumps is true? A. The inner race should be free to turn on the shaft. B. The outer race should be free to turn its housing. C. Alignment is not a critical factor in their installation. D. They are usually pressed on to their shafts. Answer-D 24. The static suction head of a pump is the A. distance of the suction liquid level above the center line of the pump B. distance the suction liquid level is below the center line of the pump C. force necessary to overcome frictional losses in the pump and piping. D. amount in inches of mercury the total suction head is below atmospheric pressure Answer-A 25. Which of the following form of inert gas is not used on gas carrier? A. Inert gas from combustion type generators. B. Nitrogen from shipboard production system. C. Pure nitrogen taken from shore D. Inert gas generated in ship's boilers. Answer-D (Because in gas tanker v use to have IG GENERATOR, NITROGEN GENERATOR AND ALSO TAKE NITROGEN FROM SHORE IF NITROGEN GENERATOR IS NOT FITTED ONBOARD) 26. The gland packing on centrifugal pump shaft should: A. Not allow any leakage under positive suction pressure B. Should only allow drop by drop continuous leakage under positive suction pressure C. Should only allow drop by drop continual leakage under positive suction pressure D. Should allow considerable leakage as gland packings are meant to allow considerable leakage Answer-C 27. 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 centrifugal compressors 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 Answer-C 28. A partial opening of which of the following kinds of valves can lead to wire-drawing of its seat? A. Globe Valve B. Butterfly valve C. Gate Valve D. Full bore angle valve Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 5 Marine Engineers and Superintendents Technical Support http://MarEngine.com 29. Scale formation in a fresh water generator evaporator can lead to _____________ A. Impaired heat transfer B. Reduced capacity C. Increased shell temperature D. All of the above Answer-D 30. The pumps performance depends upon A. Clearance between the wear ring and the impeller B. Clearance between the impeller and the casing C. Clearance between impeller and shaft D. Clearance between mechanical seal and shaft Answer-B 31. Mechanical seal are not used in _____ A. liquid line B. liquid with vapor line C. liquid with dirt line D. all of the above Answer-B 32. A pump being used to deballast for peak tank which is full, it seen that suction pressure is Positive and this pressure is very low compared to rated discharge head, it indicates that A. Pump is not operating satisfactorily n pump capacity is too low B. Pump is not operating satisfactorily n Pumping capacity is higher than rated, Throttling of discharge valve is reqd. C. Pumping capacity is not affected by suc n discharge pressure D. Pump is operating normally Answer-May be D Not Sure 33. Which of the following can lead to premature failure of roller bearings? A. Misalignment B. Contamination C. Shrinkage D. Over greasing Answer-D 34. Pump, when coupled to constant speed motor, the discharge quantity will not change with following pumps A. heleshaw B. steering gear swash plate type C. Gear pump D. None Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 6 Marine Engineers and Superintendents Technical Support http://MarEngine.com 35. If a bilge pump is able to develop vacuum, but is unable to sufficiently pump out the bilges, you would check for ________. A. the circuit breaker B. for leaks in the suction piping C. relief valve is not properly seated D. the suction strainer Answer-4 36. Which of the following is the material used for manufacturing tube plates of a shell and tube type heat exchanger? A. Cupro-nickel B. Aluminum Brass C. Admiralty Brass D. Gunmetal Answer-C Multiple Choice Question 37. Amount of distilled water produced in fresh water generator onboard decreases with A. Increase in vacuum in the fresh water generator shell B. Decrease in sea water temperature C. Decrease in efficiency of heat exchanger D. Increase in sea water temperature Answer-C and D 38. Which of the following is most suited to act as a deck air compressor? A. Lobe type B. Reciprocating type C. Screw type D. None of the above Answer-C 39. Which of the listed conditions can lead to capitation in a centrifugal pump? A. Vapor pockets formed in the suction flow stream B. Rough casing volute surfaces C. Worn wearing rings D. Heavy fluid in the flow stream Answer-A 40. What is a function of the wearing rings used in most centrifugal pumps? A. Absorb erosion of high velocity discharge stream B. Seal pump shaft against entry of air C. Isolate the discharge side from the suction side D. Dampen the turbulent discharge flow Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 7 Marine Engineers and Superintendents Technical Support http://MarEngine.com 41. Frequent cutting- in & cutting -out of a fresh water pump on a hydrophone system indicates which of the following? A. Nothing abnormal B. Excessive air charge C. Insufficient air charge D. The differential setting between cut-in and cut out is too low Answer-D 42. In case of failure of the control system of a centrifuge, the correct sequence for manually desludging a purifier would be _______ A. Stop feed-give sealing water-close sealing water -shut operating water-open and close desludging water quickly B. Stop feed- shut operating water-open and close desludging water quickly C. Shut operating water-stop feed- open sealing water for a short time then close-open and close desludging water quickly D. Shut operating water- stop feed- open and close desludging water quickly Answer-A 43. Which of the following is NOT a true statement? A. Butterfly valves are used for modulating flow and can be throttled B. Globe Valves can be straight flow or angle flow type C. Swing check valve will provide lesser resistance than same bore diameter globe type check valve D. In a globe type valves, mechanical seals are used for providing sealing between the valve bonnet and the spindle Answer-D 44. What ensures correction axial location of a thin shell bearing in its housing, for correct alignment of the oil holes? A. The nip or crush of the bearing B. Location tangs or pegs C. Dowels or keys D. None of the above Answer-A 45. Auto Clean filter are cleaned by Means of A. Compressed air B. Turning the spindle C. Backflushing D. All of the above Answer-B 46. Which of the following statement is false. A. I G is required in gas carrier B. I G is required in cofferdam C. I G is not mandatory D. None of the above Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 8 Marine Engineers and Superintendents Technical Support http://MarEngine.com 48. A multistage centrifugal pump is normally used A. High head B. High discharge flow C. High viscous fluids D. Low viscous fluid Answer-A 49. In which of the following steering modes, rudder will be locked at a particular angle until next manual order? A. Follow up B. Auto pilot C. Non Follow up D. None of the above Answer-C 50. Coked material remaining after an oil has been exposed to high temperature, is an indication of the coke forming tendency of the oil. It can be expressed as A. Conradson B. Ramsbottom C. Micro Carbon Residue (MCR) D. Any of the above Answer-D These questions mainly were taken from the website http://www.class4exam.com. Thanks for web site administration and marine engineers who shared your experience. Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 9 Marine Engineers and Superintendents Technical Support http://MarEngine.com 50 Questions and Answers For Marine Engineers Issue 6 Auxiliary Equipment Operation & Service Manuals, and Spare Parts Catalogs http://engine.od.ua Marine spare parts and equipment http://brovertek.com Marine Engineers and Superintendents Technical Support http://MarEngine.com 1. It is given that engine room bilge pump has suction manifold on which 3 valves are located. One valve for the 3 engine room bilge wells suction, another one for Bilge tank suction and the third one is for sea water suction. It is found that the Bilge pump is unable to take suction from any of the bilge wells, but is able to take suction efficiently from Bilge tank. What is the most probable cause? A. Pump suction filter cover gasket leaking B. Suction filter cover gasket of one of the Bilge wells is leaking C. Bilge well suction pipeline leaking between individual bilge well valves and suction manifold valve D. Bilge pump suction pipeline leaking between the manifold and the pump Answer-C 2. Which factor must be considered when determining the order of loading of dissimilar products through the same piping system aboard a tanker? A. Contamination of the cargo B. Flash points C. Reid vapor pressures D. Specific gravities Answer-Not Sure 3. Leaking valves in a low pressure, reciprocating, air compressor can result from ________ A. excessive compressor discharge pressure B. operating the compressor at excessive speed C. uneven piston stroke in the compressor D. abrasion by dust and dirt Tricky Question Answer will be anyone of them But You Have to Choose the Most Appropriate 4. When the control lever actuates in steering gear. A. run two motors and the control can be actuated B. by manual operation C. run one motor and control can be achieved Answer-B 5. Overall length of pairs of rams is reduced in which of the following tiller designs of a steering gear arrangement? A. Forked tiller design B. Round arm tiller design C. Conventional tiller design D. None of the above Answer-A 6. Inert Gas System on board tankers is used during which of the following operations____ A. Inerting of empty tanks B. Inerting during crude oil washing C. Purging before gas freeing D. All of the above Answer-D Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 1 Marine Engineers and Superintendents Technical Support http://MarEngine.com 7. The seating material for perfectly sealing type Ball valves is usually made up of A. Rubber B. PTFE or Nylon C. Rubber reinforced with steel wire D. Stainless steel Answer-B 8. F.O. transfer pump was working efficiently, but it stopped taking suction suddenly. There is a sounding of 6.0 m in the F.O. deep tank. The suction pressure gauge was renewed recently and is showing a positive pressure when pump is running, but Pump is not transferring any F.O. What is the most probable cause? A. Pump is damaged and needs overhaul B. Suction filter cover gasket might leaking C. Pump relief valve might be leaking D. The pump suction pipeline is blocked Answer-C (Because relief valve releases the excess pressure not full recirculation....but sme amt will be transferred....this was happened in my ship in LO PUMP) 9. When removing the cap from a sounding tube on a MODU, the sound of air escaping indicates _______________. A. the tank is full B. the tank may be partially flooded C. the tank level has dropped D. the tank is completely flooded Answer-B 10. Vacuum evaporators onboard are tested for max vacuum by A. pr. testing of evaporator shell B. carry out leak test for distillate pp at sea C. carry out leak test for vacuum pp and fittings D. leak test evaporator shell Answer-A and D 11. When both the steering motors are in use? 1) 12 nautical miles near port 2) pilot on-board 3) navigational prblm 4) all the above Answer-4 12. Subsequent to a oil spill in Engine Room and ingress of oil in the bilge wells ,the best course of action is to ____________________ A. Use oil spill dispersant chemical in the bilge wells B. Transfer the oily mixture and let it settle in the bilge holding tank/bilge separator tank C. Transfer the oily mixture using a portable pneumatic pump to a waste oil tank and then physically demuck and clean the bilge wells using environment friendly cleaner D. Dilute the bilge wells by flooding with water and then use the general service pump to pump out the bilges Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 2 Marine Engineers and Superintendents Technical Support http://MarEngine.com 13. 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 scavenger air. Answer-A and B 14. Electric and electro-hydraulic steering gear motors are required by Coast Guard Regulations (46 CFR) to be _________. A. protected by a circuit breaker set at 125% and a thermal overload device B. provided with a running motor overcurrent protection device C. served by a single two conductor cable D. served by two feeder circuits Answer-D (Because Steering gear motor do not have any trip for safety reason) MCQ 15. Two compressors should not be run in parallel because A. It is not efficient to run two compressors B. It will give over capacity in the system C. There is possibility of losing oil from the compressors D. A and B Answer-C Important Question for MMD 16. You have valves of same bore diameter but of different types. Which of the following is arranged in the decreasing order closing torque required for giving a perfect seal? A. Globe valve, Ball valve, Butterfly valve (rubber seat) B. Ball valve, Globe valve, Butterfly valve (rubber seat) C. Butterfly valve (rubber seat), Globe valve, Ball valve D. Globe valve, Butterfly valve (rubber seat), Ball Valve Answer-C MCQ 17. The cylinders and intercoolers of most low pressure air compressors are cooled by__. A. water B. oil C. air D. CO2 Answer-B 18. 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 the seat of the trap D. Throttle the steam inlet valve Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 3 Marine Engineers and Superintendents Technical Support http://MarEngine.com 19. Over greasing which of the following is NOT a true statement? A. Butterfly valves are used for modulating flow and can be throttled B. Globe Valves can be straight flow or angle flow type C. Swing check valve will provide lesser resistance than same bore diameter globe type check valve D. In a globe type valves, mechanical seals are used for providing sealing between the valve bonnet and the spindle 20. Centrifugal pump will typically give you a low flow rate at a lower pressure, where a piston pump will give you more pressure and higher flow rate. Is the statement correct? A. TRUE B. FALSE C. First Sentence is right. Second one is wrong D. I Don't know Answer-B 21. Why are large centrifugal pumps started with their discharge valves closed? A. To ensure proper priming B. To limit sudden rise in discharge rate C. To limit motor starting current D. To minimize starting torque on motor shaft Answer-C and D 22. Which of the following problems occurring in a hydraulic system can be caused by the use of oil having a viscosity lower than specified? A. Seal deterioration B. Fast response and hunting C. Increased power consumption D. Oil film breakdown Answer-C MMD Important Question 23. The suction pressure gauge of the Engine room bilge pump is broken and you don’t have a spare. Chief Engineer has asked you to troubleshoot the problem with Bilge pump not taking suction from Fwd (P) bilge well. You try taking suction from Fwd (S) & Aft Bilge well and find that pump is taking good suction. Thereafter you try suction from Fwd. (P) bilge well for sometime after priming with Sea Water but there is no change in level. You inspect the suction filter of the pump and find that it is very difficult to remove the same, you had to apply too much of force to lift the filter cover while normally it comes out easily. What does it indicate? A. It does not indicate anything, sometimes the filter covers are difficult to remove. B. It indicates that the suction valve of the Fwd. Bilge Pump is leaking C. It indicates that the suction filter of the Fwd. (P) bilge well is clogged completely D. Pump suction filter might be clogged Answer-C Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 4 Marine Engineers and Superintendents Technical Support http://MarEngine.com 24. Sludge pump suction pressure is going full vacuum when you start the pump taking water of double bottom tank suction you have checked the suction filter n found in clean condition. Taking suction from fuel oil sludge tank does not happen. Causes of the problem. A. Pump is not working efficiently n reqd. overhauling B. FO sludge tank suction valve is leaking C. W.O. tank D.B. tank suction pipeline has a blockage. D. Can not say what is the problem but definitely the pump needs to be opened up for overhaul Answer-B 25. A fluctuating and unsteady vacuum in an evaporator may be caused by _____________. A. wet steam entering the air ejector nozzle B. pinhole leaks in the evaporator tube nests C. rapid scaling on the evaporator tube nests D. high water levels in the last effect Answer-A 26. Which of the main shaft segments listed below, that are connected with the main engine, are coupled to the tail shaft flange? A. Thrust shaft B. Stern-tube shaft C. Intermediate shaft D. Crank shaft Answer-C 27. Piping cross-sections over 30 cm in diameter are sized by the __________. A. inside diameter B. wall thickness C. outside diameter D. threaded diameter Answer-C MMD Important Question 28. You have overhauled a centrifugal pump and while assembling forgot to install the o- ring between the sleeve (provided in way of gland packing) and the shaft. What impact does this have? (single answer) A. It will not affect the pump in any way B. It will cause leakage of fluid(air/water) in between the shaft and the sleeve and will affect the pump performance C. It will not affect the pump performance n any way but will corrode the shaft between the o-ring and shaft D. It will cause dynamic imbalance of the shaft Answer-B Spare Parts Catalogs, Operation & Service Manuals http://engine.od.ua 5 Marine Engineers and Superintendents Technical Support http://MarEngine.com 29. Correct method of greasing a centrifugal pump bearing is: A. To pump the grease until you feel high back pressure on the Grease pump B. To pump the grease for 3-4 pumping strokes of Grease pump for each bearing C. To pump the grease when the pump is stopped and drain any old grease at the same time by opening the drain plug, giving only 3-4 pumping strokes on Grease pump for each bearing. the drain plug should then be replaced D. To pump the grease when the pump is running and drain any old grease at the same time by opening the drain plug, until all the old grease is removed and new grease starts coming out of the drain, repeating same for each bearing. the drain plug should then be replaced Answer-D 30. If 3 Centrifugal pumps are running in parallel and the backpressure is substantially increased, what effect will be observed on the pumps in use. A. Flow rate will reduce. B. Increase in the pump casing temperature. C. Safety alarms and trips (high casing Temperature) will activate, if no corrective action taken D. All of the above. Answer-D 31. When specified Discharge pressure is not achieved, The Possible cause could be? A. Discharge pressure too high B. Pump speed too low C. Casing ring is worn out D. Cavitations exists E. All of the above Answer-B, C and D 32. Pump Start But Motor gets overloaded or Trip on overload. A. Alignment is wrong B. Gland packing too tight C. Worn out / Damaged ball bearing D. Cavitations exists E. All of the above Answer-A,B and C 33. Length of the rams is decreased in

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