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1 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP (Sample Examination) 9/10/2018 Page 1 of 53

2 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: 31 Choose the best answer to the following multiple choice questions. 1. In order to determine the restriction across a dry-type air filter on one of the diesel engines on your ship-docking tug, the engine should be operating at rated speed and load. What instrument would give the most accurate measurement of air filter element restriction? o (A) A bourdon tube vacuum gauge. (B) A water manometer. o (C) A mercury manometer. o (D) A bourdon tube compound gauge. If choice B is selected set score to The harbor tug to which you are assigned has a main engine fuel system as shown in the illustration. Besides preventing the attached fuel oil pump and the hand priming fuel oil pump from discharging through the other, what other purpose do the anti-flood check valves serve? Illustration MP-FO-06 (A) They prevent backflow of fuel from the engine to the day tank when the engine is shutdown and when the day tank is located below the engine. o (B) They prevent backflow of fuel from the engine to the day tank when the engine is shutdown and when the day tank is located above the engine. o (C) They prevent backflow of fuel from the engine to the day tank when the engine is running and when the day tank is located above the engine. o (D) They prevent backflow of fuel from the engine to the day tank when the engine is running and when the day tank is located below the engine. If choice A is selected set score to What maintenance practice represents the best protection against moisture carryover to the fuel injection system of the main engines on board your towing vessel? (A) Periodically opening, then reclosing, the drain valve on coalescing type diesel oil filters. o (B) Closing the diesel oil day tank vents, particularly when the relative humidity is high. o (C) Periodically opening, then reclosing, the vent valve on coalescing type diesel oil filters. o (D) Frequently replacing fuel injection pump and injector nozzle inlet fuel filters. If choice A is selected set score to While on deck, you are observing the stack of an oil-fired auxiliary boiler installed on your salvage tug. 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? (A) Dull or dazzling white flame. o (B) Reddish flame. o (C) Yellowish orange or golden yellow flame. o (D) Yellow flame. If choice A is selected set score to 1. 9/10/2018 Page 2 of 53

3 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The main diesel engines on your coast-wise tug are protected with an array of devices designed to provide an alarm or possible shutdown for various unsafe conditions. During the maintenance procedure for adjusting the alarm and/or trip point setting for such a device, which of the following devices would have a time delay associated with it? o (A) Engine crankcase high pressure trip/alarm device. o (B) Engine over speed trip/alarm device. (C) Engine low lube oil pressure trip/alarm device. o (D) Engine coolant high temperature alarm device. If choice C is selected set score to When interpreting the engine lube oil supply header pressures for the main engines on your river push boat, what statement is true assuming that the lube oil pump is engine-driven? o (A) As the lube oil temperature increases, the supply header pressure tends to decrease, and as the engine rpm increases, the supply header pressure tends to decrease. o (B) As the lube oil temperature increases, the supply header pressure tends to increase, and as the engine rpm increases, the supply header pressure tends to increase. (C) As the lube oil temperature increases, the supply header pressure tends to decrease, and as the engine rpm increases, the supply header pressure tends to increase. o (D) As the lube oil temperature increases, the supply header pressure tends to increase, and as the engine rpm increases, the supply header pressure tends to decrease. If choice C is selected set score to An auxiliary diesel engine on your tug uses a starting system similar to the one shown in the illustration. The hand pump is capable of charging the accumulator to the pressure necessary to start the engine and the engine successfully starts. While running, the engine driven pump is not capable of maintaining the accumulator in a state of being fully charged. Which of the following is most likely to be the cause? Illustration MP-SR-05 (A) The engine driven pump (H) drive belt is broken. o (B) The unloading valve (I) is set for too high a pressure. o (C) The full-flow filter (G) is bypassing the element. o (D) The hydro-starter (C) pistons are worn. If choice A is selected set score to You are assigned to a salvage tug fitted with main propulsion diesel engines of the type shown in the illustration. If the engine's crankshaft is turning at 720 rpm, what will be the rotational speed of the two camshafts? Illustration MO-0006 (A) 360 rpm o (B) 720 rpm o (C) 1440 rpm o (D) Not enough information is given to determine camshaft rpm. If choice A is selected set score to 1. 9/10/2018 Page 3 of 53

4 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The oil of a speed control governor on one of your tug's main diesel engines is foaming excessively, and internally governor parts are sticking due to corrosion. What is the most likely cause? o (A) The oil is excessively contaminated with solids. (B) The oil is excessively contaminated with water. o (C) The viscosity grade of the oil is improper for existing temperature conditions. o (D) The type of oil used is incompatible with governor seals. If choice B is selected set score to You are analyzing the data used for trend analysis for one of the main propulsion diesel engines on the ship-docking tug to which you are assigned. The cylinder exhaust temperature of one of the cylinders is significantly lower than the others. When analyzing compression and firing pressure data, however, the numbers are within the normal range for this particular cylinder. What condition would produce these results? o (A) Excessive carbon build-up on air inlet ports or valves of affected cylinder. o (B) Leaking fuel injector needle valve for affected cylinder. o (C) Leaking exhaust valve on affected cylinder. (D) Excessive carbon build-up on exhaust pyrometer probe of affected cylinder. If choice D is selected set score to The lubricating oil system supporting the main propulsion reduction gear on the salvage tug to which you are assigned is fitted with a sea water cooled 4-pass shell and tube lube oil cooler. The water box sacrificial zinc anodes must be inspected periodically. Which of the following listed actions correctly states maintenance criteria pertaining to scale build-up on the zincs as the result of mineral deposits (not to be confused with corrosion scaling)? o (A) Any accumulated scale build-up on sacrificial zinc anodes should be left intact to ensure proper protection from galvanic corrosion. (B) Any accumulated scale build-up on sacrificial zinc anodes should be scraped off until the zinc anodes are shiny. o (C) Any sacrificial zinc anodes with accumulated scale build-up should be replaced regardless of the degree of deterioration. o (D) There is no need to check for scale build-up on the sacrificial zinc anodes as this phenomenon is not physically possible. If choice B is selected set score to 1. 9/10/2018 Page 4 of 53

5 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The rated speed of the main propulsion diesel engines on your towing vessel is 900 rpm. The installed centrifugal over speed trip device similar to the one shown in the illustration is designed to shutdown the engine at 110% of rated speed. Upon testing the over speed trip device, you determine that the actual shutdown occurs at 945 rpm. Which of the following would account for this? Illustration MP-SF-06 o (A) The throw-out weight (item 10) link bolt (item 15 and 16) is binding within the spring guide (item 14) drilling. o (B) The throw-out weight (item 10) pivot bolt (not labelled) is binding within the counterweight (item 1 through 9) drilling. (C) The jam nut was not properly tightened against the adjusting nut (items 13) when the over speed trip was last set. o (D) The compression spring (item 12) was excessively compressed when the over speed trip was last set. If choice C is selected set score to In a closed, re-circulating fresh water cooling system used for the main engines on your sea-going salvage tug, what function would chemical treatment with nitrites primarily perform? o (A) Freezing point depression. o (B) Boiling point elevation. (C) Corrosion inhibition. o (D) Biological growth inhibition. If choice C is selected set score to The generator drive diesel engines on your river push boat are fitted with a multi-plunger injection pump with high pressure fuel lines leading to each hydraulically operated injector. If the engine is allowed to run out of fuel, it may become necessary to purge the high pressure fuel lines of air. How is this accomplished? (A) Slackening each high pressure fuel line fitting at the fuel injector while cranking over the engine with the starter or rotating the injection pump by hand and allowing air to escape, then retightening when a solid stream of fuel is observed. o (B) Slackening each high pressure fuel line fitting at the fuel injector while stroking the manually operated priming pump and allowing air to escape, then retightening when a solid stream of fuel is observed. o (C) Slackening each high pressure fuel line fitting at the fuel injector while cranking over the engine with the starter or rotating the injection pump by hand and allowing air to escape, then retightening when air bubbly fuel is observed. o (D) Slackening each high pressure fuel line fitting at the fuel injector while stroking the manually operated priming pump and allowing air to escape, then retightening when bubbly fuel is observed. If choice A is selected set score to 1. 9/10/2018 Page 5 of 53

6 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The diesel engines on your towing vessel are all protected with dry-type air filters. The air filters should be inspected and replaced in accordance with manufacturer instructions. What is the generally accepted criteria that would dictate when filter replacement becomes necessary? (A) The air filter element should be replaced when the pressure drop across the element increases above the specified maximum. o (B) The air filter element should be replaced when the pressure rise across the element decreases below the specified minimum. o (C) The air filter element should be replaced when the pressure drop across the element decreases below the specified minimum. o (D) The air filter element should be replaced when the pressure rise across the element increases above the specified maximum. If choice A is selected set score to You suspect that a diesel generator set on your salvage tug has a defective unit injector because the engine, although warm, is running roughly. The two-stroke engine is fitted with mechanically operated unit injectors. When you push and hold down the No. 3 cylinder injector follower, there is no real change, as the engine continues to run roughly as before. What does this indicate? o (A) Either the No. 4, No. 5, or No. 6 cylinder unit injector is faulty. The No. 1 and No. 2 cylinder unit injectors are functioning properly. o (B) The No. 3 cylinder unit injector is functioning properly. One of the other cylinder unit injectors must be faulty. o (C) Either the No. 1 or No. 2 cylinder unit injector is faulty. The No. 4, No. 5 and No. 6 cylinder unit injectors are functioning properly. (D) The No. 3 cylinder unit injector is faulty. You have successfully isolated the faulty unit injector. If choice D is selected set score to When rolling over a main engine on your river push boat prior to starting with the cylinder test valves open to expel any fluids accumulated within the cylinders, a rather large amount of water is discharged. What is the appropriate response? (A) Do not allow the engine to be started until the cause of the water discharge has been determined and corrected. o (B) Start the engine, but monitor all fluid levels very closely, especially that of the jacket water. o (C) Start the engine, but run the engine with the cylinder test valves cracked slightly open. o (D) Start the engine, but maintain the jacket water expansion tank level higher than normal. If choice A is selected set score to 1. 9/10/2018 Page 6 of 53

7 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: When cleaning burner atomizers associated with an oil-fired auxiliary boiler fitted on your harbor tug, which of the following metals would be recommended to use in fabricating a tool for the purposes of carbon removal? o (A) Titanium o (B) Chrome-moly steel (C) Copper o (D) Tungsten If choice C is selected set score to The ship-docking tug 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 If choice B is selected set score to The harbor tug to which you are assigned is fitted with 4-stroke cycle, 6-cylinder in-line diesel generator sets. Using the chart shown in the illustration, what is the firing order of the engines? Illustration MP-HS-05 o (A) o (B) (C) o (D) Not enough information is provided to determine the firing order. If choice C is selected set score to The main propulsion main engines on the ship-docking tug to which you are assigned are fitted with turbochargers as shown in the illustration. What statement is true concerning the over-running clutch and gear-drive train as fitted to this turbocharger type? Illustration MP-CA-08 o (A) The turbocharger is gear-driven under all engine load and starting conditions, and as such is considered both exhaust gas and mechanically driven. o (B) The turbocharger is free-wheeling and exhaust gas driven under all engine load and starting conditions, and mechanical drive arrangements are for emergency use only. (C) The turbocharger is gear-driven from the engine under low load and starting conditions only. Under high load conditions, the turbocharger is free-wheeling and exhaust gas driven. o (D) The turbocharger is gear-driven from the engine under high load conditions only. Under low load and starting conditions, the turbocharger is free-wheeling and exhaust gas driven. If choice C is selected set score to 1. 9/10/2018 Page 7 of 53

8 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The main propulsion engines onboard your harbor tug use a lubricating oil system as shown in the illustration. What item number represents the scavenging lube oil pump? Illustration MP-LO-07 o (A) 2 (B) 4 o (C) 9 o (D) 12 If choice B is selected set score to The ship-docking tug to which you are assigned has diesel generators fitted with unit injectors with the operating principle as shown in the illustration. What statement is true concerning the beginning and ending of injection? Illustration MP-FI-12 o (A) Injection begins when the upper fuel port is covered by the upper helix of the upward moving plunger, and injection ends when the lower fuel port is uncovered by the lower helix of the upward moving plunger. (B) Injection begins when the upper fuel port is covered by the upper helix of the downward moving plunger, and injection ends when the lower fuel port is uncovered by the lower helix of the downward moving plunger. o (C) Injection begins when the lower fuel port is covered by the lower helix of the downward moving plunger, and injection ends when the upper fuel port is uncovered by the upper helix of the downward moving plunger. o (D) Injection begins when the lower fuel port is covered by the lower helix of the upward moving plunger, and injection ends when the upper fuel port is uncovered by the upper helix of the upward moving plunger. If choice B is selected set score to The winch drive engine on the harbor tug 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 (A) Rotor "1" turns counter-clockwise, and rotor "2" turns clockwise. Area "3" is the discharge passage, and area "4" is the suction passage. o (B) Rotor "1" turns clockwise, and rotor "2" turns counter-clockwise. Area "3" is the suction passage, and area "4" is the discharge passage. o (C) Rotor "1" turns clockwise, and rotor "2" turns counter-clockwise. Area "3" is the discharge passage, and area "4" is the suction passage. o (D) Rotor "1" turns counter-clockwise, and rotor "2" turns clockwise. Area "3" is the suction passage, and area "4" is the discharge passage. If choice A is selected set score to 1. 9/10/2018 Page 8 of 53

9 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: You are on a ship-docking tug using main propulsion engines of the type shown in the illustration. Assuming that the piston is properly positioned, what statement represents the procedure for inspection of the compression rings while in place inside the engine? Illustration MP-MS-07 (A) It is not possible to inspect the compression rings while in place inside the engine. o (B) The inspection takes place by removing the appropriate side cover and viewing through the resulting opening. o (C) The inspection takes place by removing the appropriate crankcase access door and viewing through the resulting opening. o (D) The inspection takes place by removing the appropriate cylinder head valve cover and viewing through the resulting opening. If choice A is selected set score to Exhaust system back pressure is customarily measured at the discharge of a turbocharger. If the exhaust system back pressure is higher than normal for a given engine load on your salvage tug at the point of measurement, which of the following conditions would most likely account for this? o (A) Restricted turbocharger turbine inlet screen. o (B) Restricted turbocharger air intake filter. (C) Restricted exhaust silencer/muffler. o (D) Restricted exhaust ports or valves. = If choice C is selected set score to Prior to starting a main propulsion diesel engine fitted on your salvage tug, it has been determined that the transfer of make-up oil is required. At what checked level should you stop adding make-up oil? (A) When the oil level rises to the FULL mark on the side of the dipstick marked ENGINE STOPPED and OIL COLD. o (B) When the oil level rises to the between the ADD and FULL marks on the side of the dipstick marked ENGINE STOPPED and OIL COLD. o (C) When the oil level rises to the ADD mark on the side of the dipstick marked ENGINE STOPPED and OIL COLD. o (D) When the oil level rises to a level well above the FULL mark on the side of the dipstick marked ENGINE STOPPED and OIL COLD. If choice A is selected set score to 1. 9/10/2018 Page 9 of 53

10 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: An engine that runs rough or expels large amounts of black smoke may indicate a misfiring cylinder. Assume that the auxiliary diesel engines on your river push boat 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 the engine is running and noting the engine response. If before the injector is disabled the engine is running rough and expelling large amounts of black smoke, and after the injector is disabled, the engine continues to run equally rough, but the engine now produces a clear stack, what is indicated? o (A) This indicates that the cylinder associated with the disabled injector is firing properly, but at least one other injector is misfiring. (B) This indicates that the cylinder associated with the disabled injector is misfiring, but all other injectors are firing properly. o (C) This indicates that the cylinder associated with the disabled injector is misfiring, and at least one other injector is misfiring. o (D) This indicates that the cylinder associated with the disabled injector is firing properly, and all other injectors are firing properly. If choice B is selected set score to The engine manufacturer for the main engines used on your harbor tug specifies a supplemental coolant additive consisting of molybdate and nitrite be used to supplement the heavy-duty antifreeze for the closed, re-circulating fresh water cooling system. A test-strip comparison chart as shown in the illustration is used for coolant testing purposes. If the molybdate concentration color corresponds to row 2 and the nitrite concentration color corresponds to column B, what statement is true? Illustration MP-WC-12 o (A) The molybdate and nitrite concentrations levels are too high, and a portion of the coolant must be drained and replaced with fresh water. (B) The molybdate and nitrite concentrations levels are too low, and additional supplementary coolant additive is required. o (C) The molybdate and nitrite concentrations levels are within acceptable limits, and no further correction is required. o (D) It is not possible to determine the molybdate and nitrite concentration levels from the information given. If choice B is selected set score to 1. 9/10/2018 Page 10 of 53

11 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The fresh water cooling systems serving the main engines on your ship-docking tug are arranged as shown in the illustration. If coolant drain valves are inadvertently opened during engine operation, what combination set of symptoms would most likely result? Illustration MP-CW-16 o o (A) Low level in the jacket water expansion tank. Low fresh water outlet temperature from the engine. Low fresh water pump(s) discharge pressure. (B) High level in the jacket water expansion tank. High fresh water outlet temperature from the engine. High fresh water pump(s) discharge pressure. (C) Low level in the jacket water expansion tank. High fresh water outlet temperature from the engine. Low fresh water pump(s) discharge pressure. o (D) Low level in the jacket water expansion tank. High fresh water outlet temperature from the engine. High fresh water pump(s) discharge pressure. If choice C is selected set score to The auxiliary oil-fired water-tube steam boiler on your tug is equipped with a water column similar to that shown in the illustration. The most accurate way to determine the boiler water level is by alternately opening and reclosing the tri-cocks. At what point is the normal operating water level (NOWL) of the boiler? Illustration MO-0093 o (A) At a point coinciding with the uppermost tri-cock. (B) At a point coinciding with the middle tri-cock. o (C) At a point coinciding with the lowermost tri-cock. o (D) The level can normally be anywhere within the water column. If choice B is selected set score to After a main diesel engine on your river push boat 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 excessively rapid cooling. (B) Opening the crankcase before 2 hours has elapsed may result in a crankcase explosion. o (C) Opening the crankcase before 2 hours has elapsed may result in crankshaft rotation. o (D) Opening the crankcase before 2 hours has elapsed may result in the engine spontaneously restarting. If choice B is selected set score to 1. 9/10/2018 Page 11 of 53

12 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: A diesel engine driven winch on your towing vessel is fitted with a reversing reduction gear equipped with dry-type friction clutches. Which of the operational conditions listed below is most likely to result in clutch slippage and associated clutch disc wear? o (A) Habitually disengaging the clutch at engine idle speed. o (B) Habitually disengaging the clutch at high engine speed. o (C) Habitually engaging the clutch at engine idle speed. (D) Habitually engaging the clutch at high engine speed. If choice D is selected set score to The river pushboat to which you are assigned is fitted with main propulsion reduction gears as shown in the illustration. What statement is true concerning this type of reduction gear? Illustration MP-DS-16 o (A) This type of reduction gear is used with a controllable pitch propeller and a non-reversing engine. o (B) This type of reduction gear is used with a controllable pitch propeller and a reversing engine. (C) This type of reduction gear is used with a fixed pitch propeller and a non-reversing engine. o (D) This type of reduction gear is used with a fixed pitch propeller and a reversing engine. If choice C is selected set score to The generator drive engines fitted on your articulated tug-barge unit are started by the type of starter shown in figure "B" of the illustration. What is the purpose of the gear train situated between the air turbine rotor shaft and the pinion shaft? Illustration MP-SR-09 o (A) It DECREASES the speed of the pinion shaft as compared to the air turbine rotor shaft for the purposes of DECREASING starter motor torque. o (B) It INCREASES the speed of the pinion shaft as compared to the air turbine rotor shaft for the purposes of INCREASING starter motor torque. o (C) It INCREASES the speed of the pinion shaft as compared to the air turbine rotor shaft for the purposes of DECREASING starter motor torque. (D) It DECREASES the speed of the pinion shaft as compared to the air turbine rotor shaft for the purposes of INCREASING starter motor torque. If choice D is selected set score to You are replacing an automotive type cooling water thermostat on one of the diesel generator sets on your ship docking tug. The markings on the original thermostat indicate that it was set to begin opening at 180 o F. Which of the following thermostats marked for Celsius would be a replacement that comes closest to the value at which opening begins as compared to the original thermostat? o (A) 70 o C (B) 80 o C o (C) 90 o C o (D) 100 o C If choice B is selected set score to 1. 9/10/2018 Page 12 of 53

13 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: In preparation for getting a tug-barge unit underway, if enough time has elapsed since the last main engine shutdown, it may be necessary to blow down the engine's cylinders to expel any accumulated water or oil. What statement concerning cylinder blow down is true? o (A) The engine is rolled over with fuel delivery and with the cylinder test valves (indicator cocks) open. o (B) The engine is rolled over with fuel delivery and with the cylinder test valves (indicator cocks) closed. (C) The engine is rolled over with no fuel delivery and with the cylinder test valves (indicator cocks) open. o (D) The engine is rolled over with no fuel delivery and with the cylinder test valves (indicator cocks) closed. If choice C is selected set score to The main engines on your ocean-going tug are fitted with speed control governors of the type shown in the illustration. What is the purpose of the compensation system, consisting of the buffer cylinder, buffer piston, buffer springs, and compensation needle valve? Illustration MP-GV-14 (A) It prevents engine hunting when responding to load changes. o (B) It limits engine speed to a maximum value to prevent over speeding. o (C) It senses the actual engine speed of rotation. o (D) It senses the engine speed setting delivered from the bridge. If choice A is selected set score to The ship-docking tug to which you are assigned has a fire pump drive engine as shown in the illustration. What statement concerning common air inlet and exhaust outlet pressures is true, if the engine is running at rated speed? Illustration MP-IX-11 o (A) There is no predictable, consistent relationship between the common exhaust outlet and air inlet pressures. (B) The common exhaust outlet pressure will be lower than the common air inlet pressure. o (C) The common exhaust outlet pressure will be equal to the common air inlet pressure. o (D) The common exhaust outlet pressure will be higher than the common air inlet pressure. If choice B is selected set score to The harbor tug to which you are assigned has main engines fitted with open type combustion chambers featuring direct injection. Of the listed figures below found in the illustration, which figure represents the most likely type of injector nozzle type? Illustration MP-FI-18 (A) 1 o (B) 2 o (C) 3 o (D) 4 If choice A is selected set score to 1. 9/10/2018 Page 13 of 53

14 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: You have just replaced a mechanically operated unit injector on a two-stroke cycle auxiliary diesel engine's #1 cylinder on your river push boat. You are using an injector timing tool to set the injector follower height. To do this you must ensure that the fuel cam follower is riding on the fuel cam base circle. Which of the following statements represents the best assurance that the crankshaft is properly positioned? o (A) The crankshaft should be barred in the direction of rotation until the #1 cylinder's intake valves are fully opened. o (B) The crankshaft should be barred in the direction of rotation until the #1 cylinder's intake valves are fully closed. (C) The crankshaft should be barred in the direction of rotation until the #1 cylinder's exhaust valves are fully opened. o (D) The crankshaft should be barred in the direction of rotation until the #1 cylinder's exhaust valves are fully closed. If choice C is selected set score to Assuming the use of ultra-low sulfur content diesel fuel, what combination of conditions associated with harbor tug engine room operations would require the most frequent draining of exhaust systems of condensation? o (A) Summer operations with prolonged idling on station. o (B) Winter operations with lengthy ship escort transit times. o (C) Summer operations with lengthy ship escort transit times. (D) Winter operations with prolonged idling on station. If choice D is selected set score to In terms of the diesel fuels burned in auxiliary and main propulsion diesel engines used on board towing vessels, which of the listed fuel properties would be most critical to consider when transferring and forwarding fuel in extremely low ambient temperature conditions? o (A) Heating value o (B) Ash content (C) Pour point o (D) Flash point If choice C is selected set score to You are inspecting the blower of a Roots-blown, two-stroke cycle main propulsion engine on the ocean-going tug to which you are assigned and discover the presence of aluminum dust on the rotors and on the air duct surfaces. What would most likely be the direct cause of this? o (A) Restricted scavenging air intake ports. (B) Worn blower rotor shaft bearings. o (C) Restricted blower air intake filter. o (D) Worn blower rotor shaft seals. If choice B is selected set score to 1. 9/10/2018 Page 14 of 53

15 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The thermal fluid heating oil system on your articulated tug-barge unit is configured similarly to that shown in the illustration. What system component performs expansion and dearation functions? Illustration MP-SP-23 o (A) 1 o (B) 2 o (C) 4 (D) 5 If choice D is selected set score to A main propulsion diesel engine on your ship-docking tug has experienced a safety shutdown due to high lubricating oil temperature. What is the appropriate response? o (A) Immediately restart the engine, and monitor the oil temperature to verify the cause of the shutdown. o (B) Immediately perform the engine inspections to determine the cause of the high oil temperature safety shutdown. o (C) Allow the engine to cool off for two minutes, then restart and monitor the lubricating oil temperature to verify the cause of the shutdown. (D) Allow 2 hours for the engine to cool down before attempting to inspect the engine and correct the cause of the trip before attempting to restart the engine. If choice D is selected set score to The deck winch drive engine onboard your salvage tug uses a lubricating oil filtration scheme as shown in the illustration. What type of filtration system is illustrated? Illustration MP-LO-06 o (A) Sump filtration o (B) Shunt filtration (C) Bypass filtration o (D) Full-flow filtration If choice C is selected set score to 1. 9/10/2018 Page 15 of 53

16 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: What statement concerning fuel cetane rating and the ignition delay period is true as it applies to towboat main propulsion diesel engines? o o (A) The ignition delay period is the lag in time between when fuel injection actually begins and when combustion actually begins, and the higher the cetane rating of the fuel the longer the ignition delay period. (B) The ignition delay period is the lag in time between when fuel injection is initiated and when fuel injection actually begins, and the higher the cetane rating of the fuel the shorter the ignition delay period. (C) The ignition delay period is the lag in time between when fuel injection actually begins and when combustion actually begins, and the higher the cetane rating of the fuel the shorter the ignition delay period. o (D) The ignition delay period is the lag in time between when fuel injection is initiated and when fuel injection actually begins, and the higher the cetane rating of the fuel the longer the ignition delay period. If choice C is selected set score to The tractor tug to which you are assigned has main engines fitted with intake and exhaust systems as shown in the illustration. What statement best describes the configuration of the multiple turbochargers? Illustration MP-IX-08 (A) Two (2) turbochargers are used, one for each cylinder bank, to reduce exhaust back pressure. o (B) Four (4) turbochargers are used and configured in series for a four-staging effect to boost charge air pressure. o (C) Two (2) turbochargers are used and configured in series for a two-staging effect to boost charge air pressure. o (D) Four (4) turbochargers are used, two for each cylinder bank, to reduce exhaust back pressure. If choice A is selected set score to You are assigned to a river push boat fitted with main propulsion diesel engines operating on the cycle represented in the polar timing diagram shown in the illustration. In consideration of the direction of rotation, what combustion cycle event occurs from point "A" to point "D"? Illustration MO o (A) Compression (B) Intake o (C) Exhaust o (D) Power If choice B is selected set score to 1. 9/10/2018 Page 16 of 53

17 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: Since towing vessels take on fresh water from shore as a source of make-up water for the closed, re-circulating cooling water systems supporting diesel engines, what property of the make-up water is most important in contributing to cooling system problems? o (A) The degree of contamination of suspended solids, such as sand. o (B) The degree of contamination with microbiological organisms. o (C) The amount of dissolved oxygen (and other various gases). (D) The amount of dissolved solids associated with mineral content. If choice D is selected set score to The fresh water cooling systems serving the main engines of the towing vessel to which you are assigned are arranged as shown in the illustration. What statement best describes the arrangement of the fresh water keel cooler shown in the system diagram? Illustration MP-CW-16 o (A) The keel cooler is mounted on the outside of the hull above the water line. (B) The keel cooler is mounted on the outside of the hull below the water line. o (C) The keel cooler is mounted on the inside of the hull below the water line. o (D) The keel cooler is mounted on the inside of the hull above the water line. If choice B is selected set score to The generator drive engines fitted on your harbor tug are started by the type of starter shown in figure "A" of the illustration. What type of starter is shown? Illustration MP-SR-09 o (A) Radial piston hydraulic motor o (B) Turbine type air motor (C) Axial piston hydraulic motor o (D) Sliding vane air motor If choice C is selected set score to The tractor tug to which you are assigned is fitted with main propulsion diesel engines of the type shown in the illustration. In terms of valve operating gear, cylinder liner type, and connecting rod type, what statement is true? Illustration MP-MS-12 o (A) This is a pushrod operated overhead valve engine, with jacketed cylinder liners and conventional connecting rods. o (B) This is a pushrod operated overhead valve engine, with wet cylinder liners and hinged-strap, fork-and-blade connecting rods. (C) This is an overhead cam engine, with jacketed cylinder liners and hinged-strap, fork-andblade connecting rods. o (D) This is an overhead cam engine, with wet cylinder liners, and marine-type connecting rods. If choice C is selected set score to 1. 9/10/2018 Page 17 of 53

18 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: Regarding the high-pressure pump of a reverse osmosis fresh water generator, what statement is true? o (A) The high-pressure pump is typically a two-stage centrifugal pump, but may be a twostage rotary pump. o (B) The high-pressure pump is typically a single-cylinder reciprocating pump, but may be a singlestage centrifugal pump. o (C) The high-pressure pump is typically a two-stage rotary pump, but may be a two-stage centrifugal pump. (D) The high-pressure pump is typically a multiple-cylinder reciprocating pump, but may be a multi-stage centrifugal pump. If choice D is selected set score to A diesel generator set on your salvage tug has a simplex lube oil strainer of the type shown in the illustration, situated on the discharge side of the lube oil pump. At a specified engine rpm and lube oil temperature, you notice that the pressure drop becomes unacceptably high. When you rotate the cleaning handle, you notice that it is extremely difficult to rotate. What should be done? Illustration MO-0057 (A) After stopping the engine, the strainer element should be withdrawn and soaked in solvent to break up the heavy deposits on the disk stack (C). o (B) After stopping the engine, the drain plug (B) should be removed to drain the accumulated sludge from the strainer sump. o (C) No special consideration need be taken as long as the cleaning handle (A) rotates, even if it rotates with great difficulty. o (D) The cleaning handle (A) should be forced to rotate, even if it requires an extender handle to produce greater rotating torque. If choice A is selected set score to The two-stroke cycle main propulsion engines on the harbor tug to which you are assigned are fitted with turbochargers for scavenging purposes. Assume that you are checking the air box drains in an installation that is valved with external drain piping to a drains tank. When you open the air box drain valves, no drainage occurs when in fact there is an accumulation of oil and moisture on the floor of the air boxes. What should you do? o (A) Blow through the drain openings with compressed air to clear the drains. o (B) Increase the crankcase pressure to blow the air box drain openings clear. o (C) Increase the air box pressure to blow the air box drain openings clear. (D) Mechanically poke through the drain openings with a rod to clear the drains. If choice D is selected set score to 1. 9/10/2018 Page 18 of 53

19 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The pneumatic propulsion control system used on your towing vessel is configured as shown in the illustration. In terms of clutch air system maintenance, what statement best represents operational requirements? Illustration MP-IC-12 o (A) Whereas the cleanliness of clutch air is critical, the dryness and pressure are clutch air are of secondary concern. o (B) Whereas the dryness of clutch air is critical, the pressure and cleanliness of the clutch air are of secondary concern. o (C) Whereas the clutch air pressure is critical, the dryness and cleanliness of the clutch air are of secondary concern. (D) The pressure, dryness, and cleanliness of clutch air are all critical to successful pneumatic propulsion control operations. If choice D is selected set score to The river push boat to which you are assigned has diesel generators fitted with intake and exhaust systems as shown in the illustration. What does the component labeled "2" represent? Illustration MP-IX-06 o (A) Exhaust manifold o (B) Wet muffler (C) Charge air manifold o (D) Charge air cooler If choice C is selected set score to The towing vessel to which you are assigned is fitted with a pneumatic propulsion control system as shown in the illustration. If propulsion control functions perfectly from the engine room control station, but will not function at all from any of the remote stations, 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 local port. o (B) The pilot house/remote transfer valve at the pilot house has a blocked remote port. o (C) The attendance valve at the pneumatic remote control station has a blocked outlet port. (D) The local/remote transfer valve at the engine room control station has a blocked remote port. If choice D is selected set score to The ocean-going tug to which you are assigned is fitted with auxiliary engines as partly shown in the illustration. What statement is true concerning the valve guide and valve seat arrangements? Illustration MP-HS-03 o (A) The valve guides are replaceable inserts, and the valve seats are integral (non-replaceable). o (B) The valve guides are integral (non-replaceable), and the valve seats are replaceable inserts. o (C) The valve guides and the valve seats are both integral (non-replaceable). (D) The valve guides and the valve seats are both replaceable inserts. If choice D is selected set score to 1. 9/10/2018 Page 19 of 53

20 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The ship-docking tug to which you are assigned is fitted with a totally pneumatic propulsion control system as shown in the illustration. If the astern clutch fails to engage from the engine room control station, but engages properly from all remote control stations, 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 local port. o (B) The astern clutch engagement pilot air tubing has separated from the clutch actuator 4-way control valve at the clutch control panel. (C) The control lever at the engine room control station has a blocked astern clutch engagement pilot port. o (D) The clutch actuator 4-way control valve at the clutch control panel has a restricted astern clutch quick exhaust port opening. If choice C is selected set score to When checking the crankcase oil level on an off-line diesel generator set engine on your shipdocking tug, what should be the oil level as indicated on the dipstick? o (A) The level should be below the ADD mark on the dipstick. (B) The level should be between the FULL and ADD marks on the dipstick. o (C) The level should be well above the FULL mark on the dipstick. o (D) The actual level is unimportant as long as it is visible on the dipstick. If choice B is selected set score to Suppose the diesel generator set drive engines are of the type shown in the illustration on your ship docking tug. What description best represents the operating cycle and aspiration method? Illustration MP-HS-07 o (A) Crankcase scavenged, two-stroke cycle engine. o (B) Naturally aspirated, two-stroke cycle engine (C) Roots-blown, two-stroke cycle engine. o (D) Roots-blown, four-stroke cycle engine. If choice C is selected set score to Suppose the main propulsion diesel engines on your river pushboat are fitted with pressurecompensated governors as shown in the illustration. What function does the engine lube oil pressure connection provide? Illustration MP-GV-03 o (A) It is used as a governor lubricant and as a hydraulic power medium for the power cylinder. o (B) It is used solely for the purpose of achieving engine shutdown on low engine lube oil pressure. o (C) It is used solely for the purpose of activating an alarm on low engine lube oil pressure. (D) It is used for both activating an alarm and achieving engine shutdown on low engine lube oil pressure. If choice D is selected set score to 1. 9/10/2018 Page 20 of 53

21 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The main propulsion diesel engines used to power the ship-docking tug to which you are assigned are started with vane-type air-starting motors designed to operate at 250 psig. The in-line lubricator should provide 3 drops of oil per cranking minute, as long as the in-line lubricator oil viscosity is as specified. If the start air pressure is within the normal range and the oil viscosity is correct, but the oil injection rate is only 1 drop per minute, what should be done? o (A) The in-line lubricator oil injection metering needle valve should be further closed. (B) The in-line lubricator oil injection metering needle valve should be further opened. o (C) The starting air pressure supplied to the air-starting motors should be increased. o (D) The oil in the in-line lubricator should be replaced with oil of lower viscosity than specified. If choice B is selected set score to Suppose one of the overhead camshafts on the V-type main propulsion diesel engines on your tug are fitted on the forward end with the device shown in the illustration. In addition to serving as a counterweight, what other function does the device serve? Illustration MP-SF-06 o (A) Torsional vibration damper (B) Overspeed trip o (C) Overload sensor o (D) Harmonic balancer If choice B is selected set score to Which tugboat 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. (B) Maintaining relatively low day tank levels when the relative humidity of the atmosphere is high. o (C) Maintaining relatively high 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 low. If choice B is selected set score to The main engines on your harbor tug are equipped with over speed trip devices as shown in the illustration. By what method is the engine shutdown on an over speed condition? Illustration MP-IC- 15 (A) A trip shaft cam positions all the unit injectors plungers to the bottom of their respective strokes, preventing plunger reciprocation, which results in engine shutdown. o (B) A solenoid valve in the common fuel supply line to the unit injectors is closed, which results in engine shutdown. o (C) A trip shaft cam positions all the unit injectors plungers to the top of their respective strokes, preventing plunger reciprocation, which results in engine shutdown. o (D) The fuel control linkage controlling the unit injector racks goes to the no fuel position, which results in engine shutdown. If choice A is selected set score to 1. 9/10/2018 Page 21 of 53

22 U.S.C.G. Merchant Marine Exam DDE-Unlimited HP Illustrations: The salvage tug to which you are assigned has main engines fitted with intake and exhaust systems as shown in the illustration. Assume that the vacuum between the air filter and the turbocharger blower inlet is 12" of water column (negative with respect to atmospheric pressure) when the engine is running at 50% of maximum, continuous rated load. What will happen to the suction vacuum when the load is increased to 100% of maximum continuous rated load? Illustration MP-IX-14 o (A) The depth of vacuum will decrease (reading less inches of water column negative with respect to atmospheric pressure). o (B) No change in the depth of vacuum will occur (reading the same inches of water column negative with respect to atmospheric pressure). (C) The depth of vacuum will increase (reading more inches of water column negative with respect to atmospheric pressure). o (D) A loss of vacuum will occur (now reading inches of water column positive with respect to atmospheric pressure). If choice C is selected set score to 1. 9/10/2018 Page 22 of 53

23 MO /3/2016 Adapted for testing purposes only from WILBUR, Pounder's Marine Diesel Engines, Sixth edition Copyright 1986 Butterworth's Publishers Further reproduction prohibited without permission. Page 23 of 53

24 A MO-0057 D C B 4/15/2015 Adapted for testing purposes only from GUNTHER, Lubrication. Copyright 1971 by Raymond C. Gunther. Further reproduction prohibited without permission. Page 24 of 53

25 MO /22/2018 Adapted for testing purposes only from Engineman 3 Copyright NAVEDTRA Further reproduction prohibited without permission. Page 25 of 53

26 MO /10/2016 Adapted for testing purposes only from MAGNETROL, Installation, Maintenance, Operating Instructions for Models W126, W127, W251, W252, W291 Copyright Magnetrol division of Schaub Engineering Co. Further reproduction prohibited without permission. Page 26 of 53

27 MP-CA-08 EMD Turbocharger Adapted for testing purposes only from 645E7B Turbo Marine Engine/Systems, 1 st Edition 9/15/2017 Copyright 1980 by Electro-Motive Division of General Motors Page 27 of 53 Further reproduction prohibited without permission

28 MP-CA-09 3/1/2018 Adapted for testing purposes only from KATES/LUCK, Diesel and High Compression Gas Engines, 3 rd edition Copyright 1974 by American Technical Society Further reproduction prohibited without permission. Page 28 of 53

29 MP-CW-16 EMD Engine Fresh Water Cooling System with Keel Cooler 8/2/2017 Adapted for testing purposes only from Marine Propulsion Unit Operating Manual Copyright 1988 by Electro-Motive Division, General Motors Corporation Page 29 of 53 Further reproduction prohibited without permission

30 MP-DS-16 Reversing Reduction Gear Operation 8/3/2017 Adapted for testing purposes only from Engineman 3 NAVEDTRA Further reproduction prohibited without permission Page 30 of 53

31 MP-FI-12 Detroit Diesel 71 Series Engine Unit Injector 8/10/2017 Adapted for testing purposes only from NORMAN Diesel Technology: Fundamentals, Service, Repair Copyright 2007 by The Goodheart-Wilcox Company, Inc. Page 31 of 53 Further reproduction prohibited without permission

32 National Maritime Center MP-FI-18 9/22/2017 Adapted for testing purposes only from NORMAN Diesel Technology: Fundamentals, Service, Repair Copyright 2007 by The Goodheart-Wilcox Company, Inc. Page 32 of 53 Further reproduction prohibited without permission

33 MP-FO-06 EMD 645 Series Engine Fuel Oil System 8/14/2017 Adapted for testing purposes only from Marine Propulsion Unit Operating Manual Copyright 1988 by Electro-Motive Division, General Motors Corporation Page 33 of 53 Further reproduction prohibited without permission

34 MP-GV-03 Woodward Type PGA Governor Schematic Diagram 10/2/2017 Adapted for testing purposes only from 645E7B Turbocharged Marine Engine/Systems, 1 st Edition Copyright 1980 Electro-Motive Division of General Motors Page 34 of 53 Further reproduction prohibited without permission

35 MP-GV-14 10/10/2017 Adapted for testing purposes only from PGA Marine Governor Copyright 1975 by Woodward Governor Company Further reproduction prohibited without permission Page 35 of 53

36 MP-HS-03 10/23/2017 Adapted for testing purposes only from TOBOLDT, Diesel Fundamentals, Service, Repair Copyright 1973 by the Goodheart-Willcox Co., Inc. Further reproduction prohibited without permission. Page 36 of 53

37 MP-HS-05 10/12/2017 Adapted for testing purposes only from STINSON, Diesel Engineering Handbook, 12 th Edition Copyright 1981 by Business Journals, Inc. Further reproduction prohibited without permission. Page 37 of 53

38 MP-HS-07 10/17/2017 Adapted for testing purposes only from TOBOLDT, Diesel Fundamentals, Service, Repair Copyright 1973 by the Goodheart-Willcox Co., Inc. Further reproduction prohibited without permission. Page 38 of 53

39 MP-IC-12 Pneumatic Propulsion Control System 8/15/2017 Adapted for testing purposes only from Falk Marine Reduction Drives, Installation, Operation and Maintenance Manual Copyright 1976 Faulk Page 39 of 53 Further reproduction prohibited without permission.

40 MP-IC-15 EMD 645 Overspeed and Manual Trips Adapted for testing purposes only from 645E7B Turbocharged Marine Engine/Systems, 1 st Edition 8/18/2017 Copyright 1980 by Electro-Motive Division of General Motors Page 40 of 53 Further reproduction prohibited without permission

41 MP-IX-06 10/25/2017 Adapted for testing purposes only from WOODYARD, Pounder s Marine Diesel Engines and Gas Turbines Copyright 2009 by Elsevier, Ltd. Further reproduction prohibited without permission Page 41 of 53

42 MP-IX-08 9/5/2017 Adapted for testing purposes only from KNAK, Diesel Motor Ships Engines and Machinery; Diagrams Copyright 1990 by The Institute of Marine Engineers Page 42 of 53 Further reproduction prohibited without permission

43 MP-IX-11 Generic Turbocharged 2-Stroke Engine Intake and Exhaust Systems 10/27/2017 Adapted for testing purposes only from KATES, Diesel and High Compression Gas Engines, 3 rd Edition Copyright 1974 by American Technical Society Page 43 of 53 Further reproduction prohibited without permission

44 MP-IX-14 7/5/2016 Adapted for testing purposes only Further reproduction prohibited without permission. Page 44 of 53

45 MP-LO-06 Simplified Lube Oil Filtration System 10/30/2017 Adapted for testing purposes only from NORMAN Diesel Technology: Fundamentals, Service, Repair Copyright 2007 by The Goodheart-Wilcox Company, Inc. Page 45 of 53 Further reproduction prohibited without permission

46 MP-LO-07 12/4/2017 Adapted for testing purposes only from BAKER, Diesel Engines and Electric Power Copyright 1998 by The University of Texas at Austin Further reproduction prohibited without permission Page 46 of 53

47 MP-MS-07 ALCO 251 Series Engine 11/16/2017 Adapted for testing purposes only from ALCO 251 Instruction Manual Copyright ALCO Further reproduction prohibited without permission Page 47 of 53

48 MP-MS-12 3/5/2018 Adapted for testing purposes only from EMD 645E9 Turbocharged Engine Maintenance Manual Copyright 1973 Electro-Motive Division, General Motors. Further reproduction prohibited without permission. Page 48 of 53

49 MP-SF-06 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 Further reproduction prohibited without permission. Page 49 of 53 9/20/2016

50 MP-SP-23 Thermal Fluid Heating Oil System 8/25/2017 Adapted for testing purposes only from Fulton Installation and Operation Manual Vertical Coil Design Thermal Fluid Heater Model FT-C and FT-S Copyright 2013 by The Fulton Companies Further reproduction prohibited without permission Page 50 of 53

51 MP-SR-05 A B D C E F I H G Adapted for testing purposes only from CATERPILLAR, Service Manual, D353 Industrial and Marine Engines. Copyright Caterpillar. 3/18/2015 Further reproduction prohibited without permission. Page 51 of 53

52 MP-SR-09 Starting Motors Fig. A: Adapted for testing purposes only from STINSON, Diesel Engineering Handbook Copyright 1981 by Business Journals, Inc. Further reproduction prohibited without permission 11/29/2017 Fig. B: Adapted for testing purposes only from KUIKEN, Diesel Engines for Ship Propulsion and Power Plants Copyright 2012 by Target Global Energy Training Further reproduction prohibited without permission Page 52 of 53

53 MP-WC-12 11/30/2017 Adapted for testing purposes only from Acustrip CTS-4 Four-Way Antifreeze Specifications & Instructions Copyright 2013 by Acustrip Company Further reproduction prohibited without permission Page 53 of 53