U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680 ... · provided an abnormal method of reassembly is ... Thermostatically controlled electric water jacket heater ... Lower heat

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U.S.C.G. Merchant Marine Exam

Chief Engineer-OSV

Q680 Motor Plants

(Sample Examination)

Page 1 of 39 Q680 Motor Plants

5/25/2018

U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17

Choose the best answer to the following Multiple Choice questions.

1. The anchor-handling vessel to which you are assigned has a pneumatic propulsion control system as shown in the illustration. Which control valve is responsible for by-passing the inflation delay orifice to insure rapid and positive reversals and to protect the clutches from excessive slip? Illustration MP-IC-08

• (A) H5 boost relay air valve. o (B) H5 inflation air relay valve. o (C) C2 speed-slip relay valve. o (D) H5 governor limit relay air valve.

If choice A is selected set score to 1.

2. The oil platform supply vessel to which you are assigned is fitted with a pneumatic propulsion control system as shown in the illustration. If the astern clutch fails to engage from all control locations, but the ahead clutch properly engages from all control locations, which of the following system faults best accounts for these symptoms? Illustration MP-IC-12

o (A) The ahead clutch engagement pilot air tubing has separated from the clutch actuator 4-way control valve at the clutch control panel.

• (B) The astern clutch engagement pilot air tubing has separated from the clutch actuator 4-way control valve at the clutch control panel.

o (C) The control lever at the pneumatic remote control station has a blocked astern clutch engagement pilot port.

o (D) The control lever at the engine room control station has a blocked astern clutch engagement pilot port.

If choice B is selected set score to 1.

3. According to the manufacturer's recommendations for a main propulsion diesel engine on an oil rig supply vessel where the fuel oil day tank is above the engine, the maximum allowable pressure drop across the primary suction fuel filter element is 1.5 psig. What would be the equivalent pressure drop in inches of mercury, when the fuel oil day tank is below the engine?

o (A) 0.75" Hg o (B) 1.5" Hg • (C) 3.0" Hg o (D) 6.0" Hg

If choice C is selected set score to 1.


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4. A turbocharged, two-stroke cycle main propulsion diesel engine on your offshore supply vessel is emitting gray to black smoke excessively from the stack. Upon comparing the measured air box pressure against a reference engine, which is producing a clear stack, the measured air box pressure is determined to be too low. Which of the following conditions would most likely be the cause for the relatively low air box pressure?

o (A) Turbocharger exhaust turbine inlet screen is excessively restricted. o (B) Scavenging air intake ports are excessively restricted with carbon deposits. o (C) Exhaust silencer/muffler is excessively restricted with carbon deposits. • (D) Airside aluminum fins on after coolers are excessively restricted.

If choice D is selected set score to 1.

5. While warming up the main engines on your offshore utility vessel while tied up at your own pier, one of the main engines suddenly sounds the low lube oil pressure alarm. What is the appropriate initial response?

• (A) Immediately shutdown the engine, then investigate the cause for the low-pressure alarm. o (B) Reduce the load and speed on the engine and continue to monitor the oil pressure. o (C) Monitor closely oil pressures, temperatures, and levels while continuing to run the engine. o (D) Immediately add make-up oil or service lube oil coolers, strainers, and filters, as appropriate.


6. Prior to starting the main propulsion diesel engines fitted on your platform supply vessel, the crankcase oil level must be checked. At what checked level would you be required to add make-up oil?

• (A) When the oil level drops below the ADD mark on the side of the dipstick marked ENGINE STOPPED and OIL COLD.

o (B) When the oil level drops to between the ADD and FULL marks on the side of the dipstick marked ENGINE STOPPED and OIL COLD.

o (C) When the oil level drops below the FULL mark on the side of the dipstick marked ENGINE STOPPED and OIL COLD.

o (D) When the oil level drops to where it is no longer visible on the side of the dipstick marked ENGINE STOPPED and OIL COLD.



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7. You are about to perform valve stem to rocker arm clearance adjustments on an auxiliary diesel engine onboard your offshore supply vessel. Which of the following statements concerning hot and cold clearances is true?

• (A) When comparing hot and cold valve clearances, the hot clearance will always be less than the cold clearance for a given valve application.

o (B) When comparing hot and cold valve clearances, it is not possible to predict the hot and cold clearances relative to one another for a given valve application.

o (C) When comparing hot and cold valve clearances, the hot clearance will always be greater than the cold clearance for a given valve application.

o (D) When comparing hot and cold valve clearances, the hot and cold valve clearances for a given valve application will always be identical.


8. The drilling platform supply vessel to which you are assigned has diesel generators fitted with unit injectors of the type shown in the illustration. What statement is true concerning the operation of unit injectors of this type? Illustration MP-FI-10

• (A) Pressurization of the fuel is accomplished by the mechanically operated rocker arm, and the timing and metering of the fuel is accomplished by the electronically controlled solenoid.

o (B) Pressurization of the fuel is accomplished by the electronically controlled solenoid, and the timing and metering of the fuel is accomplished by the mechanically operated rocker arm.

o (C) Pressurization and timing of the fuel is accomplished by the mechanically operated rocker arm, and the metering of the fuel is accomplished by the electronically controlled solenoid.

o (D) Pressurization and metering of the fuel is accomplished by the mechanically operated rocker arm, and the timing of the fuel is accomplished by the electronically controlled solenoid.


9. When starting a deck winch drive engine in preparation for cargo handling operations, what parameter must be checked FIRST upon start-up to avoid immediate engine damage?

o (A) Fuel oil supply header pressure. o (B) Deck winch gear oil pump discharge pressure. o (C) Cylinder jacket water pump discharge pressure. • (D) Engine lubricating oil supply header pressure.



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10. The lube oil quality management system used on your general-purpose supply vessel requires on board testing of lubricating oil to include testing for viscosity at the same temperature consistently. In terms of viscosity test results, what statement is true?

o (A) An unusual drop in viscosity indicates excessive oxidation of the lubricating oil OR excessive dilution of the lubricating oil with diesel fuel oil OR BOTH.

o (B) An unusual drop in viscosity indicates excessive oxidation of the lubricating oil and an unusual rise in viscosity indicates excessive dilution of the lubricating oil with diesel fuel oil.

• (C) An unusual drop in viscosity indicates excessive dilution of the lubricating oil with diesel fuel oil and an unusual rise in viscosity indicates excessive oxidation of the lubricating oil.

o (D) An unusual rise in viscosity indicates excessive oxidation of the lubricating oil OR excessive dilution of the lubricating oil with diesel fuel oil OR BOTH.


11. You are assigned to an OSV fitted with main propulsion diesel engines operating on the cycle represented in the polar timing diagram shown in the illustration. When do the exhaust valves open and close respectively? Illustration MO-0084

• (A) The exhaust valves open at 55o before bottom dead center on the power stroke. The exhaust valves close at 85o after top dead center on the intake stroke.

o (B) The exhaust valves open at bottom dead center at the beginning of the exhaust stroke. The exhaust valves close at top dead center at the end of the exhaust stroke.

o (C) The exhaust valves open at top dead center at the end of the exhaust stroke. The exhaust valves close at bottom dead center at the beginning of the exhaust stroke.

o (D) The exhaust valves open at 85o after top dead center on the intake stroke. The exhaust valves close at 55o before bottom dead center on the power stroke.


12. The fresh water cooling systems serving the main engines on your offshore supply vessel are arranged as shown in the illustration. If there is excessive scale build up inside the tubes of an engine's shell and tube RW/FW heat exchanger, while the engine is in operation, what would be the resulting symptoms? Illustration MP-CW-15

o (A) A decreased temperature rise on the raw waterside, and an increased temperature drop on the fresh waterside.

o (B) A increased temperature rise on the raw waterside, and an increased temperature drop on the fresh waterside.

o (C) A increased temperature rise on the raw waterside, and a decreased temperature drop on the fresh waterside.

• (D) A decreased temperature rise on the raw waterside, and a decreased temperature drop on the fresh waterside.



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U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 13. You are analyzing the data used for trend analysis for a two-stroke main propulsion diesel engine on

your general-purpose supply vessel. Although the engine has yet to experience a safety shutdown on high crankcase pressure, over time the crankcase pressure (which normally runs in a vacuum) has gradually become less negative. Which of the following failures would most likely be responsible for this condition?

• (A) Worn piston compression rings o (B) Burned cylinder exhaust valve o (C) Dribbling injector needle valve o (D) Leaking crankcase handhold cover


14. The diesel engines on your anchor-handling supply vessel are all protected with dry-type air filters. When changing filter elements what visual indication would cause you to suspect that the engine has been contaminated with dust as the result of improperly sealing of the filter element gasket?

o (A) The "dirty" side of the air filter housing is coated with dust. • (B) The "clean" side of the air filter element is streaked with dust. o (C) The "dirty" side of the air filter element is coated with dust. o (D) The "clean" side of the air filter element is clean and free of dust.


15. Which statement most accurately represents the requirements for softening hard carbon deposits associated with the burner atomizers of an auxiliary boiler as fitted on your anchor-handling supply vessel?

• (A) Carbon should be softened by soaking in diesel fuel or kerosene. o (B) Carbon should be softened by blowing through with steam. o (C) Carbon should be softened by soaking in hot soapy water. o (D) Carbon should be softened by soaking in sulfamic or hydrochloric acid.


16. An engine that runs rough may indicate a misfiring cylinder. Various techniques associated with disabling the injectors sequentially, in turn, may be used to locate the misfiring cylinder on auxiliary diesel engines of the size used on offshore supply vessels. What type of fuel injectors are disabled for troubleshooting purposes by loosening the high-pressure fuel injection line fitting at the injector nozzle?

o (A) Mechanically operated unit injectors where each injection pump plunger and injection nozzle are integrated into one self-contained unit.

o (B) Mechanically operated injection nozzles where each nozzle is supplied by a separately housed pressure/time (PT) metering pump.

o (C) Electronically operated unit injectors where each injection pump plunger and injection nozzle are integrated into one self-contained unit.

• (D) Hydraulically operated injection nozzles where each nozzle is supplied by separately housed injection pump plungers in a multi-plunger pump.



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U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 17. Due to the questionable mineral content of fresh water taken on from shore as a source of make-up

water for diesel engine closed, recirculating cooling water systems, besides chemical treatment and coolant testing, what is the best line of defense in minimizing cooling system problems?

o (A) Maintaining cooling water temperatures at higher than normal values. o (B) Increasing the frequency of draining, flushing, and re-filling the system. • (C) Maintaining a tight system and promptly repairing leaks. o (D) Maintaining cooling water temperatures at lower than normal values.


18. The main engines on your anchor handling supply boat utilize a starting system similar to that shown in the illustration. The air supply pressure and engine room ambient temperatures are both within the normal range. Upon attempted start-up, the engine turns very slowly, and the flow rate of air from the air starting motor exhaust is very low. Which of the listed conditions would most likely be the cause of the failure to start? Illustration MP-SR-13

o (A) The air-starting motor vanes are stuck in their slots. o (B) The in-line lubricator siphon tube is severely restricted. o (C) The fuel injection system piping is air-bound. • (D) The in-line strainer basket element is severely restricted.


19. The platform construction support vessel to which you are assigned has a deck winch drive engine fitted with fuel injectors with the operating principle as shown in the illustration. In figure "A”, which plunger travel position corresponds to when fuel injection begins? Illustration MP-FI-12

o (A) 1 • (B) 2 o (C) 3 o (D) 4


20. The main diesel propulsion engines on your offshore supply vessel are protected with a mechanical overspeed trip mechanism similar to that shown in the illustration. Upon testing the trip setting, you discover that it is necessary to make an adjustment. Assuming that several adjustments may be necessary before the final setting is accurately achieved, what statement concerning adjustment is true? Illustration MO-0101

o (A) To adjust the overspeed trip, the engine must be stopped AND the locknut must be retightened only after the final adjustment.

• (B) To adjust the overspeed trip, the engine must be stopped AND the locknut must be retightened after each adjustment.

o (C) To adjust the overspeed trip, the engine must be running AND the locknut must be retightened after each adjustment.

o (D) To adjust the overspeed trip, the engine must be running AND the locknut must be retightened only after the final adjustment.



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U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 21. You are preparing to change the oil of the speed control governor on one of the main propulsion

diesel engines on your OSV. What statement is true concerning the draining and flushing procedures?

• (A) The governor oil should be drained while the oil is hot and the governor should be flushed with the lightest grade of the same type of oil.

o (B) The governor oil should be drained while the oil is hot and the governor should be flushed with the heaviest grade of the same type of oil.

o (C) The governor oil should be drained while the oil is cold and the governor should be flushed with the heaviest grade of the same type of oil.

o (D) The governor oil should be drained while the oil is cold and the governor should be flushed with the lightest grade of the same type of oil.


22. The turbocharged, four-stroke, main propulsion diesel engines on your offshore supply vessel are protected with dry-type air intake filters. The engines are fitted with dial-type restriction indicators measuring the pressure in the air duct between the air intake filter and the turbocharger blower inlet. Under what conditions should the air intake filters be evaluated using the restriction indicators?

o (A) The engine should be running at rated RPM with no load (propulsion clutch disengaged). o (B) The engine should be running at idle RPM with no load (propulsion clutch disengaged). • (C) The engine should be running at rated RPM with full load (propulsion clutch engaged). o (D) The engine should be running at idle RPM with minimal load (propulsion clutch engaged).


23. Assuming the use of low sulfur content diesel fuel, what combination of conditions associated with offshore supply vessel engine room operations would most contribute to internal corrosion of exhaust systems?

o (A) Low ambient temperature and high engine load. o (B) High ambient temperature and high engine load. • (C) Low ambient temperature and low engine load. o (D) High ambient temperature and low engine load.



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24. The fresh water cooling systems serving the main engines of your offshore supply vessel are of the type shown in the illustration. What statement accurately describes the characteristics of the fresh water cooling circuit? Illustration MP-CW-15

o (A) The fresh water circuit is a vented system using an automotive type 2-way thermostatic control valve for temperature control.

o (B) The fresh water circuit is a pressurized system using an automotive type 2-way thermostatic control valve for temperature control.

o (C) The fresh water circuit is a pressurized system using a stationary/marine type 3-way thermostatic control valve for temperature control.

• (D) The fresh water circuit is a vented system using a stationary/marine type 3-way thermostatic control valve for temperature control.


25. A main engine speed control governor for one of your offshore supply vessel's main propulsion engines hunts, surges, or is sluggish to respond to load changes. Which of the following governor oil conditions would be the greatest single source of governor troubles?

o (A) Foamy oil (air entrainment). o (B) Wrong grade of oil (viscosity). • (C) Dirty oil (solid contaminants). o (D) Wrong type of oil (composition).


26. For diesel engines, such as those used for main propulsion and auxiliary power on offshore supply vessels, while running at speed, how is the ignition of fuel within the cylinder achieved?

o (A) Ignition is achieved by the heat of compression created by compressing the air/fuel mixture within the cylinder into a relatively small volume.

• (B) Ignition is achieved by the heat of compression created by compressing intake/charge air within the cylinder into a relatively small volume.

o (C) Ignition is achieved by intense heat by passing electric current through the element of a specially designed glow plug.

o (D) Ignition is achieved by a high voltage electric spark induced across the gap of a specially designed spark plug.



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27. Your general-purpose supply vessel is fitted with a coil-type, water-tube, forced-circulation auxiliary boiler. What statement best represents the conditions associated with coil watersides inspection and cleaning?

o (A) Coil watersides are relatively easy to inspect AND mechanical cleaning with water jet or wire brush is a practical and efficient method of scale removal.

• (B) Coil watersides are very difficult to inspect AND chemical cleaning with a suitable acid is the only practical and efficient method of scale removal.

o (C) Coil watersides are relatively easy to inspect AND chemical cleaning with a suitable acid is the only practical and efficient method of scale removal.

o (D) Coil watersides are very difficult to inspect AND mechanical cleaning with water jet or wire brush is a practical and efficient method of scale removal.


28. In a closed, recirculating fresh water cooling system used for the diesel-generators on your offshore supply vessel, what function would chemical treatment with organic phosphates primarily perform?

o (A) Biological growth inhibition. • (B) Scale control and suppression. o (C) Freezing point depression. o (D) Corrosion inhibition.


29. After performing repairs on the fuel injection system or governor of a main propulsion diesel engine on your offshore platform supply vessel, what precaution should be taken prior to starting the engine?

o (A) Provisions should be made to shut off the engine's lubricating oil supply to stop the engine in case there is an overspeed on start-up.

o (B) Provisions should be made to shut off the engine's control electrical power supply to stop the engine in case there is an overspeed on start-up.

o (C) Provisions should be made to shut off the engine's starting air supply to stop the engine in case there is an overspeed on start-up.

• (D) Provisions should be made to shut off the engine's inlet air and/or fuel supply to stop the engine in case there is an overspeed on start-up.



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30. The main engines on your anchor handling supply vessel are equipped with manual shutdown levers as shown in the illustration. What statement concerning manual shutdown is true? Illustration MP-IC-15

o (A) The manual shutdown lever is operated by means of a remote pull cable and uses the governor fuel control linkage to accomplish engine shutdown.

• (B) The manual shutdown lever is operated by means of a remote pull cable and uses the over speed trip mechanism to accomplish engine shutdown.

o (C) The manual shutdown lever is operated by means of the emergency trip reset lever and uses the governor fuel control linkage.

o (D) The manual shutdown lever is operated by means of the over speed trip reset lever and uses the over speed trip mechanism to accomplish engine shutdown.


31. Due to environmental and safety concerns, the towing winch drive diesel engine cooling water system is treated with propylene glycol for protection against freezing. According to the illustration, what would be the limit of protection if 40 pints of propylene glycol were used in treating a cooling water system with a volumetric capacity of 10 gallons? Illustration MP-WC-04

o (A) 10oF o (B) -6oF • (C) -30oF o (D) -53oF


32. The raw water boxes of the fresh water coolers serving the main propulsion diesel engines on your offshore supply vessel are fitted with sacrificial zinc anodes. Upon inspection, at what percentage of deterioration should the zinc anodes be replaced?

o (A) 25% • (B) 50% o (C) 75% o (D) 100%



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33. You are about to check the valve lash adjustment on #1 cylinder's intake and exhaust valves of an auxiliary diesel engine fitted on the anchor-handling supply vessel to which you are assigned. You want to adjust the valve lash on both valves without having to reposition the crankshaft between adjustments. What should be the position of #1 piston to insure both the intake and exhaust valves are both in a position to facilitate valve adjustment?

• (A) The crankshaft should be barred in the direction of rotation with #1 piston at TDC having just completed a compression stroke.

o (B) The crankshaft should be barred in the direction of rotation with #1 piston at BDC having just completed an intake stroke.

o (C) The crankshaft should be barred in the direction of rotation with #1 piston at BDC having just completed a power stroke.

o (D) The crankshaft should be barred in the direction of rotation with #1 piston at TDC having just completed an exhaust stroke.


34. You are assigned to an offshore supply vessel fitted with main propulsion diesel engines of the type shown in the illustration. How many degrees of crankshaft revolution are required for all of the engine's cylinders to fire? Illustration MP-MS-04

o (A) 180 degrees • (B) 360 degrees o (C) 720 degrees o (D) Not enough information is given to determine crankshaft degrees of revolution.


35. An engine that emits black smoke through the stack may indicate a misfiring cylinder. Assume that the auxiliary diesel engines on your oil platform supply vessel have a fuel injection system that permits the injectors to be disabled for troubleshooting purposes by loosening the high-pressure fuel injection line fitting at the injector nozzle while the engine is running and noting the response of the engine in terms emission of black smoke. Which of the following statements is true?

o (A) After disabling the injector of a given cylinder, if the engine previously producing black smoke now produces even denser black smoke, this indicates that the cylinder associated with the disabled injector is misfiring.

• (B) After disabling the injector of a given cylinder, if the engine previously producing black smoke now produces a clear stack, this indicates that the cylinder associated with the disabled injector is misfiring.

o (C) After disabling the injector of a given cylinder, if the engine previously producing a clear exhaust now produces black smoke, this indicates that the cylinder associated with the disabled injector is misfiring.

o (D) After disabling the injector of a given cylinder, if the engine previously producing black smoke continues to produce equally dense black smoke, this indicates that the cylinder associated with the disabled injector is misfiring.



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U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 36. The main propulsion diesel engines on your offshore supply vessel are fitted with mechanically

operated and controlled unit injectors. In order for the engine to run properly, the injectors must be properly timed relative to the camshaft and properly synchronized relative to the other injectors. In terms of timing and synchronization, what statement is true?

• (A) Injector timing is achieved by adjusting the cam follower heights of the injectors to the proper setting, but injector synchronization is achieved by adjusting the control racks of the injectors to the proper setting.

o (B) Injector timing is achieved by adjusting the cam follower heights of the injectors to the proper setting, and injector synchronization is also achieved by adjusting the cam follower heights of the injectors to the proper setting.

o (C) Injector timing is achieved by adjusting the control racks of the injectors to the proper setting, and injector synchronization is also achieved by adjusting the control racks of the injectors to the proper setting.

o (D) Injector timing is achieved by adjusting the control racks of the injectors to the proper setting, but injector synchronization is achieved by adjusting the cam follower heights of the injectors to the proper setting.


37. The pneumatic propulsion control system used on your anchor-handling supply vessel uses a diaphragm-operated relay valve as shown in the illustration. Periodically, the valve is to be disassembled for cleaning and inspection. What statement best describes the proper method for servicing the in-line strainers? Illustration MO-0052

• (A) The strainers should be cleaned and rinsed with a non-flammable solvent, then blown dry with low-pressure compressed air.

o (B) The strainers should be washed with soap and water and rinsed with fresh water, then blown dry with high-pressure compressed air.

o (C) The strainers should be cleaned and rinsed with a non-flammable solvent, then blown dry with high-pressure compressed air.

o (D) The strainers should be washed with soap and water and rinsed with fresh water, then blown dry with low-pressure compressed air.


38. The rated speed of the main propulsion diesel engines on your offshore supply vessel is 900 rpm. The installed centrifugal overspeed trip device similar to the one shown in the illustration is designed to shutdown the engine at 110% of rated speed. Upon testing the overspeed trip device, you determine that the actual shutdown occurs at 945 rpm. Which of the following would account for this? Illustration MO-0101

o (A) The throw-out weight (item #10) link bolt (item #15 & #16) is binding within the spring guide (item #11) drilling.

o (B) The throw-out weight (item #10) pivot bolt (not labeled) is binding within the counterweight (item 1 through 9) drilling.

o (C) The compression spring (item #12) was excessively compressed when the overspeed trip was last set.

• (D) The jam nut (item #14) was not properly tightened against the adjusting nut (items #13) when the overspeed trip was last set.



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U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 39. If the water level as indicated by the gauge glass of an auxiliary boiler is in question, it should be

blown down. Which of the following statements represents the proper procedure for performing a gauge glass blowdown?

• (A) The gauge glass should be blown down twice; first with the lower cut-out valve open and then with the upper cut-out valve open.

o (B) The gauge glass should be blown down twice; first with the upper cut-out valve open and then with the lower cut-out valve open.

o (C) The gauge glass should be blown down once with the lower cut-out valve open. o (D) The gauge glass should be blown down once with both the upper cut-out and lower cut-out

valves open simultaneously.


40. The main propulsion diesel engines fitted on your OSV are started with vane-type air-starting motors. What statement concerning air-start motor lubricator maintenance is true? (Assume a metal bowl fitted with a tubular sight glass.)

• (A) The lubricator reservoir bowl should be re-filled with clean oil when it becomes approximately half full as shown in the glass.

o (B) The lubricator reservoir bowl should be re-filled with clean oil when the level is no longer visible in the glass.

o (C) The lubricator reservoir bowl should be re-filled with clean oil as soon as the level drops to the very upper part of the glass.

o (D) The lubricator reservoir bowl should be re-filled with clean oil when it is estimated that the bowl is completely empty.


41. The multi-purpose supply vessel to which you are assigned has main engines fitted with injectors similar to those shown in the illustration. What statement is true concerning the operating principle of this type of injector? Illustration MP-FI-22

o (A) The fuel pressure within the annulus and the compression load on the spring are both needle valve closing forces.

o (B) The fuel pressure within the annulus is a needle valve closing force, the compression load on the spring is a needle valve opening force.

• (C) The fuel pressure within the annulus is a needle valve opening force, the compression load on the spring is a needle valve closing force.

o (D) The fuel pressure within the annulus and the compression load on the spring are both needle valve opening forces.



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42. In order to minimize the abrasive action of dust particles entering the combustion spaces of the diesel engines used on the offshore supply vessel to which you are assigned, each engine is protected with a heavy-duty air intake filter. Which one of the listed air intake filter elements is periodically cleaned as opposed to being periodically replaced with a new element?

o (A) Panel-type filter element. • (B) Wire-mesh filter element. o (C) Spiral-rotor filter element. o (D) Multi-tube filter element.


43. You suspect that a diesel generator set on your anchor-handling supply vessel has a misfiring cylinder because the engine, although warm, is running roughly. The six-cylinder engine is fitted with a multi-plunger in-line high pressure fuel injection pump with hydraulically operated injector nozzles. When you slacken the high pressure fuel line fitting at #5 fuel injector nozzle, the engine continues to run roughly as before with no real change. Upon re-tightening the high pressure fuel line fitting, the engine begins and continues to run smoothly. What does this indicate?

o (A) #5 cylinder was and continues to be firing properly. #1, #2, #3, or #4 cylinder is misfiring. # 6 cylinder is firing properly.

• (B) #5 cylinder had been misfiring. You have successfully purged the air from the #5 cylinder high pressure fuel line, and the engine is no longer misfiring.

o (C) #5 cylinder was and continues to be firing properly. #6 cylinder is misfiring. #1, #2, #3, and #4 cylinders are all firing properly.

o (D) #5 cylinder was and continues to be misfiring. You have successfully located the misfiring cylinder.


44. The winch drive engine on the anchor handling supply vessel to which you are assigned is fitted with a Roots-type blower as shown in the illustration. What statement is true concerning this blower? Illustration MP-CA-09

o (A) Rotor "1" turns counter-clockwise, and rotor "2" turns clockwise. Area "3" is the suction passage, and area "4" is the discharge passage.

o (B) Rotor "1" turns clockwise, and rotor "2" turns counter-clockwise. Area "3" is the discharge passage, and area "4" is the suction passage.

o (C) Rotor "1" turns clockwise, and rotor "2" turns counter-clockwise. Area "3" is the suction passage, and area "4" is the discharge passage.

• (D) Rotor "1" turns counter-clockwise, and rotor "2" turns clockwise. Area "3" is the discharge passage, and area "4" is the suction passage.



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U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 45. You are assigned as an engineer on an offshore platform supply vessel using main propulsion

engines of the type shown in the illustration. What statement represents the procedure for inspection of the upper cylinder liner bore while in place inside the engine? Illustration MP-MS-04

o (A) With the particular piston positioned at TDC and the corresponding oil pan handhold cover removed, inspect the upper liner bore through the scavenging air ports.

• (B) With the particular piston positioned at BDC and the corresponding air box handhold cover removed, inspect the upper liner bore through the scavenging air ports.

o (C) With the particular piston positioned at TDC and the corresponding air box handhold cover removed, inspect the upper liner bore through the scavenging air ports.

o (D) With the particular piston positioned at BDC and the corresponding oil pan handhold cover removed, inspect the upper liner bore through the scavenging air ports.


46. The offshore supply vessel to which you are assigned is fitted with reversing reduction gears equipped with airflex pneumatic tire-type friction clutches. With the bridge in control of the main engines, you hear unusual screeching noises coming from the clutches, but only when transitioning from one direction to the other. Given the situation of changing direction from ahead to astern as an example, what is the most likely cause?

o (A) The EOT handle is being left in ahead idle and then in neutral for too long a period of time. • (B) The EOT handle is being left in neutral and then in astern idle for too short a period of time. o (C) The EOT handle is being left in ahead idle and then in neutral for too short a period of time. o (D) The EOT handle is being left in neutral and then in astern idle for too long a period of time.


47. While underway in open waters on your platform supply vessel, the low clutch air pressure alarm sounds and the faint odor of burning rubber is detected. What is the appropriate response?

o (A) Reduce the load and speed on the engine, then investigate the cause of low clutch air pressure.

o (B) Investigate the cause of low clutch air pressure, then reduce the engine load and speed if necessary.

o (C) Investigate the cause of low clutch air pressure, then bring the throttle and clutch control to the stop position if necessary.

• (D) Bring the throttle and clutch control to the stop position, then investigate the cause of low clutch air pressure.



5/25/2018


48. A main propulsion diesel engine on your anchor-handling supply vessel produces gray to black smoke under virtually all load conditions as observed at the stack. The heavier the load on the engine, the darker the smoke becomes. What condition would most likely account for this?

• (A) Excessively restricted exhaust silencer/muffler. o (B) Excessively worn exhaust valve guides. o (C) Leaking exhaust piping expansion joints. o (D) Leaking exhaust manifold cooling water jackets.


49. You are observing the flame condition on an oil-fired auxiliary boiler installed on your anchor-handling supply vessel through an observation window peephole. The flame is a reddish color accompanied by a noticeably panting/pulsating furnace. What would be the correlating color of the gases exhausting from the stack under these conditions?

o (A) Light brown haze o (B) White smoke o (C) Clear stack • (D) Dense black smoke


50. The lubricating oil system supporting the main propulsion reduction gear on your offshore supply vessel is fitted with a lube oil strainer as shown in the illustration. How often should the handle "A" be rotated for cleaning purposes? Illustration MO-0057

• (A) Once per watch while underway. o (B) Once per month. o (C) Once every six months. o (D) Once per year.


51. The turbochargers on the main propulsion engines on the OSV to which you are assigned are fitted with an exhaust inlet screen to protect the turbocharger turbine. Upon inspection, pieces of broken piston rings or exhaust valves are found in the foreign object trap box. Besides removing this debris, with respect to the screen what should be done?

o (A) The screen should be placed in a press to remove any indentations from impingement. o (B) The screen should be replaced without conducting any further checking or investigation. • (C) The screen should be magnafluxed to check for damage not visible to the naked eye. o (D) The screen should be replaced only when damage is obvious to the naked eye.



5/25/2018

U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 52. Concerning the diesel fuels used for the auxiliary and main propulsion diesel engines on-board

the offshore supply vessel to which you are assigned, what fuel property is directly a measure of the ignition quality of the fuel?

o (A) Heating value o (B) Viscosity • (C) Cetane rating o (D) Density


53. The OSV to which you are assigned is fitted with hydraulic clutches similar to that shown in the illustration. If the time required for the clutch to disengage is unacceptably long, which of the following conditions would most likely be responsible for this? Illustration MO-0089

o (A) Fluid clutch sump level maintained at too high a level. o (B) Clutch operating fluid is maintained at too high a temperature. o (C) Clutch operating fluid is maintained at too low a temperature. • (D) Solid contaminants are present in the hydraulic fluid.


54. Which offshore supply boat diesel fuel oil day tank condition would be most likely to result in water-contaminated fuel?

o (A) Maintaining relatively low day tank levels when the relative humidity of the atmosphere is low. o (B) Maintaining relatively high day tank levels when the relative humidity of the atmosphere is

low. • (C) Maintaining relatively low day tank levels when the relative humidity of the atmosphere is

high. o (D) Maintaining relatively high day tank levels when the relative humidity of the atmosphere is

high.


55. The main diesel engines on the OSV to which you are assigned are fitted with a basket type lube oil strainer, which must be periodically cleaned. The engine manufacturer recommends using a petroleum based solvent for cleaning. Which of the following would typically be acceptable?

• (A) A high flash point solvent such as kerosene or diesel fuel. o (B) A low flash point solvent such as gasoline. o (C) An aromatic solvent such as benzene or toluene. o (D) A chlorinated solvent such as perchlorethylene or trichloroethylene.



5/25/2018

U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 56. The diesel fuels burned in auxiliary and main diesel engines of offshore supply vessels serving

drilling platforms are required to meet certain specifications. Among these are limits of certain contaminants to limit atmospheric emissions to acceptable levels. Which of the following soluble contaminants is applicable?

o (A) Total sediment • (B) Sulfur o (C) Water o (D) Asphaltenes


57. The offshore supply vessel to which you are assigned has a pneumatic propulsion control system as shown in the illustration. Which valve is responsible for processing a clutch inflation pressure at speed signal pilot pressure during periods of clutch slip maneuvering at low engine rpm? Illustration MP-IC-08

o (A) H5 governor limit relay air valve o (B) H5 inflation air relay valve o (C) H5 boost relay air valve • (D) C2 speed-slip relay valve


58. You suspect that a diesel generator set on your OSV has a misfiring cylinder because the engine, although warm, is running roughly. The six-cylinder engine is fitted with a multi-plunger in-line high-pressure fuel injection pump with hydraulically operated injector nozzles. When you slacken the high-pressure fuel line fitting at #3 fuel injector nozzle, the engine continues to run roughly as before with no real change. Upon re-tightening the high-pressure fuel line fitting, there is no real change, as the engine continues to run roughly as before. What does this indicate?

• (A) # 3 cylinder is misfiring. You have successfully located the misfiring cylinder. o (B) Either #4, #5 or #6 cylinder is misfiring. #1 and #2 cylinders are firing properly. o (C) # 3 cylinder is firing properly. One of the other cylinders must be misfiring. o (D) Either #1 or #2 cylinder is misfiring. #4, #5, and #6 cylinders are firing properly.


59. The tank-type full-flow lubricating oil filter is situated on the discharge side of the engine-driven lube oil pump on the main engines on your anchor-handling supply boat. Assuming oil pressure readings are observed at constant engine rpm and lube oil temperature, what is the indication of gradually clogging filter elements as long as the bypass relief valve remains closed?

o (A) The filter inlet pressure gradually drops, while the filter outlet pressure gradually rises. • (B) The filter inlet pressure gradually rises, while the filter outlet pressure gradually drops. o (C) The filter inlet AND outlet pressures BOTH gradually rise. o (D) The filter inlet AND outlet pressures BOTH gradually drop.



5/25/2018

U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 60. You are in the process of setting up a system for collecting engine data for trend analysis for the

main propulsion engines on your offshore supply vessel. In terms of the conditions under which readings are to be taken and recorded, what statement is true?

o (A) Data should be collected under conditions of load and speed as variable as possible. o (B) Data should be collected under random conditions of load and speed. o (C) Data should be collected with no particular concern for conditions of load and speed. • (D) Data should be collected under conditions of load and speed that are similar, if not constant.


61. The OSV to which you are assigned is fitted with a pneumatic propulsion control system as shown in the illustration. All propulsion controls function properly from all locations with the exception of the pneumatic remote control station. Here the propulsion engine will run only at idle and neither propulsion clutch will engage regardless of the throttle lever control position. Which of the following system faults best accounts for these symptoms? Illustration MP-IC-12

o (A) The local/remote transfer valve at the engine room control station has a blocked remote port. o (B) The attendance valve at the pilothouse pneumatic master control station has a blocked outlet

port. o (C) The throttle lever control at the pneumatic remote control station has a blocked speed signal

pilot air port. • (D) The pilot house/remote transfer valve at the pilothouse pneumatic master control station has

a blocked remote port.


62. While on deck, you are observing the stack of an oil-fired auxiliary boiler installed on your general-purpose supply vessel. The gases exiting the stack are a dense white smoke. Eliminating water vapor as a possible cause of the white smoke, what would be the correlating flame color as observed through an observation window peephole?

o (A) Yellow flame o (B) Yellowish orange or golden yellow flame o (C) Reddish flame • (D) Dull or dazzling white flame


63. The oil spill response vessel to which you are assigned is fitted with reduction gears as shown in the illustration. What statement is true concerning this type of reduction gear? Illustration MP-DS-04

o (A) The reduction gear is a double-input, double-reduction type of gear. • (B) The reduction gear is a single-input, single-reduction type of gear. o (C) The reduction gear is a double-input, single-reduction type of gear. o (D) The reduction gear is a single-input, double-reduction type of gear.



5/25/2018

U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 64. The anchor handling supply vessel to which you are assigned has diesel generators fitted with fuel

injectors with the operating principle as shown in the illustration. In figure "B”, which plunger rotation position corresponds to the engine running under no load at idle RPM? Illustration MP-FI-12

o (A) 1 • (B) 2 o (C) 3 o (D) 4


65. After a main diesel engine on your oil platform construction support vessel has experienced a safety shutdown due to excessive crankcase pressure, why is it important to wait 2 hours before opening the crankcase to investigate the cause of the trip?

o (A) Opening the crankcase before 2 hours has elapsed may result in the engine spontaneously restarting.

o (B) Opening the crankcase before 2 hours has elapsed may result in excessively rapid cooling. • (C) Opening the crankcase before 2 hours has elapsed may result in a crankcase explosion. o (D) Opening the crankcase before 2 hours has elapsed may result in crankshaft rotation.


66. Assuming the use of ultra-low sulfur content diesel fuel, what combination of conditions associated with OSV engine room operations would require the most frequent draining of exhaust systems of condensation?

o (A) Winter operations with lengthy ship escort transit times. o (B) Summer operations with lengthy ship escort transit times. o (C) Summer operations with prolonged idling on station. • (D) Winter operations with prolonged idling on station.


67. You are serving as a Chief Engineer (DDE) onboard an OSV equipped with main propulsion diesel engines of the type represented by the polar timing diagram shown in the illustration. What description best describes the engine type? Illustration MO-0084

• (A) Turbocharged, 4-stroke cycle engine. o (B) Turbocharged, 2-stroke cycle engine. o (C) Naturally aspirated, 4-stroke cycle engine. o (D) Naturally aspirated, 2-stroke cycle engine.



5/25/2018

U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680. Motor Plants Illustrations: 17 68. The fresh water cooling systems serving the main engines on your anchor-handling supply boat are

arranged as shown in the illustration. If the fresh water thermostatic control valve fails in the position where 100% of the flow from flange "A" is permanently ported to flange "C" and flange "B" is permanently blocked, while starting and warming the engine with no load, what would be the resulting warm up time period? Illustration MP-CW-15

• (A) With no load, the engine would require a much longer than normal time frame to warm up. o (B) With no load, the engine would require a relatively normal time frame to warm up. o (C) With no load, it is not possible to describe the time frame required to warm up the engine. o (D) With no load, the engine would require a much shorter than normal time frame to warm up.


69. A main propulsion diesel engine on your anchor-handling supply boat has experienced a safety shutdown on high crankcase pressure, which was accompanied by an alarm. After waiting 2 hours as recommended by the manufacturer, the crankcase is opened up and suitable repairs are accomplished. After re-closing the crankcase, the engine fails to start. Which of the following would account for this?

o (A) The high crankcase pressure detector protective device must have its diaphragm replaced first before the engine can be restarted.

o (B) The high crankcase pressure detector protective device's pressure chamber must be evacuated with a vacuum pump first before the engine can be restarted.

o (C) The high crankcase pressure detector protective device must have its switch lever replaced first before the engine can be restarted.

• (D) The high crankcase pressure detector protective device must be reset first before the engine can be restarted.


70. A Roots-blown, two-stroke cycle main propulsion engine on the platform supply vessel to which you are assigned is emitting excessive bluish-tinged smoke from the stack. Further investigation reveals excessive lube oil consumption. What condition would most likely account for this?

o (A) Restricted blower air intake filter. o (B) Leaking fuel injector needle valve. • (C) Worn blower rotor shaft seals. o (D) Restricted scavenging air intake ports.



5/25/2018


3/27/2015

MO-0052

Adapted for testing purposes only from WABTEC H5 Relayair Valve, Operation and

Maintenance Instruction. © 2000 WABCO Locomotive Products.

Further reproduction prohibited without permission. Page 23 of 39 Q680 Motor Plants


4/15/2015

MO-0057

Adapted for testing purposes only from GUNTHER, Lubrication.

Copyright © 1971 by Raymond C. Gunther.

Further reproduction prohibited without permission.

A

B

D

C



2/22/2018

MO-0084

Adapted for testing purposes only from Engineman 3 Copyright © NAVEDTRA 14331



7/25/2016

MO-0089

Adapted for testing purposes only from STINSON, Diesel Engineering Handbook, 12th

Edition

Copyright © 1981 Business Journals, Inc.



9/20/2016

MO-0101

Adapted for testing purposes only from Replacement Parts Catalog No. 302, Diesel Engine

Model 645 For Power Generation and Marine Propulsion

Copyright © 1989 Electro-Motive Division, General Motors Corporation



3/1/2018

MP-CA-09

Adapted for testing purposes only from KATES/LUCK, Diesel and High Compression Gas Engines, 3rd edition

Copyright © 1974 by American Technical Society Further reproduction prohibited without permission. Page 28 of 39

Q680 Motor Plants

National Maritime Center

Providing Credentials to Mariners

8/1/2017

MP-CW-15 EMD Engine Fresh Water

Cooling System with Heat Exchanger

Adapted for testing purposes only from Marine Propulsion Unit Operating Manual

Copyright © 1988 by Electro-Motive Division, General Motors Corporation

Further reproduction prohibited without permission



8/9/2016

MP-DS-04

Adapted for testing purposes only from Falk Marine Reduction Drives,

Installation, Operation and Maintenance Manual

Copyright © Falk




9/18/2017

MP-FI-10 Detroit Diesel 60 Series Engine

Unit Injector Arrangements

Adapted for testing purposes only from NORMAN Diesel Technology:

Fundamentals, Service, Repair

Copyright © 2007 by The Goodheart-Wilcox Company, Inc.





8/10/2017

MP-FI-12 Detroit Diesel 71 Series Engine Unit Injector








8/14/2017

MP-FI-22







11/21/2017

MP-IC-08 Pneumatic Propulsion Control System with

Single Lever Pilot House Control

Adapted for testing purposes only from Marine Reverse-Reduction Gear Controls Copyright © 1976 by the Falk Corporation





8/15/2017

MP-IC-12

Pneumatic Propulsion Control System

Adapted for testing purposes only from Falk Marine Reduction Drives,

Installation, Operation and Maintenance Manual

Copyright © 1976 Faulk

Further reproduction prohibited without permission.




8/18/2017

MP-IC-15 EMD 645 Overspeed and Manual Trips

Adapted for testing purposes only from 645E7B Turbocharged Marine Engine/Systems, 1st

Edition

Copyright © 1980 by Electro-Motive Division of General Motors

Further reproduction prohibited without permission Page 36 of 39

Q680 Motor Plants



8/17/2017

MP-MS-04

Adapted for testing purposes only from WOODYARD, Pounder's Marine Diesel Engines

and Gas Turbines, Ninth edition

Copyright © 2009 by Elsevier Ltd.

Further reproduction prohibited without permission. Page 37 of 39

Q680 Motor Plants



8/21/2017

MP-SR-13 Simplified Air Starting System

Adapted for testing purposes only from Waukesha Marine Systems Installation Manual

Copyright © 1972 by Waukesha Motor Company


Q680 Motor Plants



8/22/2017

MP-WC-04 Freezing Point of Coolant as a

Function of Glycol Concentration

Adapted for testing purposes only


Q680 Motor Plants

Documents

U.S.C.G. Merchant Marine Exam Chief Engineer-OSV Q680 ... · provided an abnormal method of reassembly is ... Thermostatically controlled electric water jacket heater ... Lower heat