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All of the latest questions and illustrations on "Engine Room Motor Propulsion" are in the Online Study.

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Engine Room Motor Propulsion

 

D The process of supplying a diesel engine cylinder with air at a pressure greater than atmospheric is called __________. engine displacement super-aspirating air injection supercharging Air- charge systems
A Forcing the exhaust gases from the cylinder of an operating two cycle diesel engine with the aid of a blower is known as __________. scavenging forced draft turbo charging aspiration Air- charge systems
A Which of the listed types of superchargers will NOT have a volumetric capacity proportional to engine speed? Exhaust gas turbocharger Roots blower Piston type blower Vane type blower Air- charge systems
A The relative air pressure in the inlet manifold of a turbocharged diesel engine is usually __________. greater than the average exhaust manifold pressure less than the average exhaust manifold pressure greater at the turbine wheel than at the impeller greater at reduced engine speed Air- charge systems
C After cooling of a turbocharged diesel engine will result in __________. higher torque but lower brake horsepower lower torque but higher brake horsepower higher torque and higher brake horsepower lower torque and lower brake horsepower Air- charge systems
B The process of scavenging a two-stroke/cycle diesel engine serves to __________. improve fuel flow volume cool the exhaust valves
reduce the intake air charge density
increase the temperature of exhaust gases Air- charge systems
B Why will a turbocharged diesel engine produce black smoke if excessive additional load is applied too quickly? Exhaust energy would draw excess air. The inertia of the turbocharger rotor causes a time lag which delays the turbocharger speed increase.
Exhaust gas pumping losses are increased due to turbine windage.
Exhaust gas back pressure falls slightly due to increased nozzle action. Air- charge systems
D According to the illustrated main engine cooling water systems drawing, which of the labeled heat exchangers represents the charge air coolers? Illustration MO-0111 3 and 4 4 and 5 4 and 6  5 and 6 Air- charge systems
D Which of the following devices will increase the power output of a diesel engine without increasing its frictional load? Positive displacement blower
 o
Roots-type rotary blower Gear-driven centrifugal blower Turbine-driven centrifugal blower Air- charge systems
B Some diesel engines are supercharged with a __________. slam charger turbocharger
 o
fuel atomizer
 o
fuel injector Air- charge systems
A The device shown in the illustration is commonly used to __________. Illustration MO-0080 utilize the flow of exhaust gases to supercharge the engine
protect the crankcase from overpressure in event of explosion
provide cooling water circulation through the engine
provide air starting pressure Air- charge systems
B At rated engine load and RPM, the diesel engine turbocharger is powered by __________. belt drive exhaust gases
electric motor
friction clutch Air- charge systems
B The operating speed of a turbocharger is directly dependent upon __________. engine speed engine load
intake manifold pressure
atmospheric pressure Air- charge systems
B What statement is true concerning the charge air system of a modern turbocharged slow-speed two-stroke cycle diesel engine? A mechanically driven auxiliary blower is usually provided because the turbocharger cannot provide enough air at low engine speeds and loads. An electrically driven auxiliary blower is usually provided because the turbocharger cannot provide enough air at low engine speeds and loads.
An electrically driven auxiliary blower is usually provided because the turbocharger cannot provide enough air at high engine speeds and loads.
A mechanically driven auxiliary blower is usually provided because the turbocharger cannot provide enough air at high engine speeds and loads. Air- charge systems
A What statement is true concerning the charge air system of a modern turbocharged slow-speed two-stroke cycle diesel engine? A charge air cooler is usually provided to increase the charge air density.
 o
A charge air heater is usually provided to decrease the charge air density.
 o
A charge air heater is usually provided to increase the charge air density.
 o
A charge air cooler is usually provided to decrease the charge air density. Air- charge systems
C On a typical turbo-charged marine diesel engine, what type of blower/compressor is used within the turbocharger? Rotary vane Rotary screw Centrifugal
 o
Axial flow Air- charge systems
D If oil discharges are detected when the scavenging air receiver drains are blown on a slow-speed, two-stroke, turbocharged, aftercooled engine, what is the most likely oil source?
Turbocharger lubricating oil Crosshead lubricating oil Bearing lubricating oil Cylinder lubricating oil Air- charge systems
C Upon conducting a machinery space round on a slow-speed main propulsion diesel, you detect a significant amount of oil discharge when blowing down the scavenging air receiver drains. What should you do? Notify the watch or duty engineer at some point during the day work period or watch. Notify the chief engineer the next time he or she is seen. Notify the watch or duty engineer immediately. Notify the first assistant engineer the next time he or she is seen. Air- charge systems
A You are asked by the watch or duty engineer to check for any evidence for turbocharger surging. What should you check for? By listening for cyclic changes in turbocharger sound pitch. By visually checking for cyclic changes in turbocharger sump oil levels. By visually checking for cyclic changes in charge air temperature. By visually checking for cyclic changes in exhaust gas temperature. Air- charge systems
C Upon conducting a machinery space round on a main propulsion diesel, you detect a significant amount of water discharge when blowing down the charge air cooler or scavenging air receiver drains. What should you do? Notify the watch or duty engineer at some point during the day work period or watch. Notify the first assistant engineer the next time he or she is seen. Notify the watch or duty engineer immediately. Notify the chief engineer the next time he or she is seen. Air- charge systems
A During the valve overlap period, the exhaust pressure of a turbocharged, four-stroke cycle diesel engine must be less than the intake manifold pressure to ensure __________. effective cylinder scavenging and cooling constant pressure from the turbochargers cooler operation of the exhaust system effective constant pressure for turbocharger operation Air- charge systems
D The power consumed during the scavenging process of a diesel engine is known as the __________. compression loss valve loss back pressure loss pumping loss Air- charge systems
C If a slow-speed two-stroke cycle diesel engine is fitted with exhaust valves located in the cylinder heads, what scavenging flow-pattern is utilized? Cross-flow scavenging Return-flow scavenging Uniflow scavenging Loop scavenging Air- charge systems
A If a slow-speed two-stroke cycle diesel engine is fitted with scavenging air ports and exhaust ports located on opposite sides of the cylinder wall, what scavenging flow-pattern is utilized? Cross-flow scavenging Uniflow scavenging  Return-flow scavenging Loop scavenging Air- charge systems
D As it applies to the combustion process associated with diesel engines, what is meant by the term "scavenging"? Scavenging is the process of filling the cylinder with a charge of fresh air ready for compression. Scavenging is the process of filling the cylinder with a charge of fresh air at pressures above atmospheric pressure. Scavenging is the process of filling the cylinder with a charge of fresh air at atmospheric pressure. Scavenging is the process of removing exhaust gases from the cylinder by blowing in fresh air. Air- charge systems
C Corrosion inhibitors and/or soluble oils are added to diesel engine cooling systems to __________. reduce the cooling water temperature increase cooling water hardness form a protective film on metal surfaces maintain low pH in the cooling water Cooling Systems
B Ethylene glycol, when used as a coolant in a closed cooling system for a diesel engine, is more advantageous than untreated raw water because it __________. has a higher freezing point and a lower boiling point has a lower freezing point and higher boiling point provides a constant pH below 7 provides better vapor-phase cooling Cooling Systems
B According to the illustrated main engine cooling water systems drawing, which labeled pump is the main engine sea water cooling water pump? Illustration MO-0111 7 8 15 20 Cooling Systems
B According to the illustrated main engine cooling water systems drawing, which labeled heat exchangers use sea water as a cooling medium? Illustration MO-0111 3, 4, 5, 6, and 23 3, 4, 5, 6, and 24 4, 5, 6, and 23 4, 5, 6, and 24 Cooling Systems
A According to the illustrated main engine cooling water systems drawing, which labeled sea water-cooled heat exchanger would have the highest sea water inlet temperature? Illustration
MO-0111
3 4 5 6 Cooling Systems
B According to the illustrated main engine cooling water systems diagram, which of the following labeled heat exchangers represents the main lube oil cooler? Illustration MO-0111 3 4 5 6 Cooling Systems
D According to the illustrated main engine cooling water systems diagram, which of the following heat exchangers would be isolated and bypassed while maneuvering in or out of port?
Illustration MO-0111
3 and 4 4 and 5  5 and 6  23 and 24 Cooling Systems
C Cooling water pumps driven by direct-reversing diesel engines are usually __________. curved impeller vane with tangential outlet straight impeller vane with tangential housing straight impeller vane with concentric housing curved impeller vane with concentric outlet Cooling Systems
A According to the illustrated diesel propulsion plant fresh water cooling systems diagram, in which subsystem is the deaerator located? Illustration MO-0072 Main engine cylinder jacket cooling water system Main engine fuel injector cooling water system SSDG cylinder jacket cooling water system Main engine piston cooling water system Cooling Systems
B The expansion tank for a diesel engine closed cooling system is designed to maintain a constant head on the system and __________. reduce water temperature allow for an increase in water volume as the engine warms up reduce water turbulence provide an air cushion Cooling Systems
C The highest pressure in any closed diesel engine freshwater cooling system is at the __________. jacket water outlet expansion tank inlet cooling water pump outlet heat exchanger inlet Cooling Systems
C The expansion tank in a diesel engine closed fresh water cooling system is located at __________. the lowest point in the system or near the tank top level the highest point in the system or near the floor plate level Cooling Systems
C A closed freshwater cooling system is commonly used with marine diesel engines because the __________. cooling water temperature differential is greater cooling water pumps are directly reversible jacket water temperature is more easily controlled need for water treatment is eliminated Cooling Systems
B Corrosion inhibitors and/or soluble oils are added to diesel engine cooling systems to __________. increase cooling water hardness form a protective film on metal surfaces reduce the cooling water temperature maintain low pH in the cooling water Cooling Systems
C According to the illustrated main and auxiliary diesel engine cooling water systems diagram, which of the following heat exchangers are connected directly in series with one another? Illustration MO-0129 Camshaft lube oil cooler and jacket water cooler Jacket water cooler and scavenge air coolers(s) Lube oil cooler and jacket water cooler Camshaft lube oil cooler and scavenge air coolers(s) Cooling Systems
B Sacrificial zinc anodes are used on the saltwater side of diesel engine heat exchangers to __________. keep heat transfer surfaces shiny and clean reduce electrolytic action on heat exchanger metals prevent rapid accumulation of marine growth provide a protective coating on heat exchanger surfaces Cooling Systems
A In a diesel engine jacket water cooler, with sea water cooling the fresh water, the __________. jacket water pressure should always be greater than the sea water pressure jacket water pressure must always be less than the sea water pressure jacket water temperature must always be less than 60F sea water temperature must never be warmer than 40F Cooling Systems
A When checking zincs in a saltwater cooled heat exchanger, you should __________. replace the zincs if they are approximately 50% consumed paint the zincs to stop corrosion file the zincs to change the shape insulate the zincs to alter the temperature Cooling Systems
A In a diesel engine lube oil cooler, with sea water cooling the lubricating oil, what statement is true? The lube oil pressure is always kept higher than the sea water pressure, and in case of a lube oil cooler leak, the lube oil sump level will decrease. The sea water pressure is always kept higher than the lube oil pressure, and in case of a lube oil cooler leak, the lube oil sump level will increase. The sea water pressure is always kept higher than the lube oil pressure, and in case of a lube oil cooler leak, the lube oil sump level will decrease. The lube oil pressure is always kept higher than the sea water pressure, and in case of a lube oil cooler leak, the lube oil sump level will increase. Cooling Systems
A in a diesel engine jacket water cooler, with sea water cooling the engine jacket cooling water, what statement is true? The jacket water pressure is always kept higher than the sea water pressure, and in case of a jacket water cooler leak, the jacket water expansion tank level will increase. he sea water pressure is always kept higher than the jacket water pressure, and in case of a jacket water cooler leak, the jacket water expansion tank level will increase. The jacket water pressure is always kept higher than the sea water pressure, and in case of a jacket water cooler leak, the jacket water expansion tank level will decrease. The sea water pressure is always kept higher than the jacket water pressure, and in case of a jacket water cooler leak, the jacket water expansion tank level will decrease. Cooling Systems
B A three-way thermostatic control valve regulates the diesel engine cooling water temperature by passing a portion of the water __________. overboard around the cooler to the expansion tank around the engine Cooling Systems
A What would be considered a normal temperature increase between the inlet and outlet jacket cooling water of a medium or high-speed diesel engine operating at normal load? 10 to 20F 1 to 5F 5 to 10F 50 to 100F Cooling Systems
B An electric heater built into some smaller diesel engines is used to __________. increase air inlet temperature increase jacket water temperature for easier starting in cold weather increase compression ratio raise lube oil viscosity for easier starting in cold weather Cooling Systems
D In a diesel engine closed freshwater cooling system employing a radiator, proper water temperature can be obtained by __________. passing cooling water through a space heater passing cooling water through the lube oil cooler piping exhaust gases across the radiator front adjusting the radiator louvers Cooling Systems
D The temperature at which an adjustable bellows type thermostatic valve operates is determined by __________. changing the position of the actuating bulb varying air loading pressure to the bellows replacing the bellows with a heavier spring changing the spring compression opposing the bellows Cooling Systems
C According to the illustrated diesel engine cooling water systems diagram, what fluid is the low temperature central fresh water thermostat designed to maintain? Illustration MO-0129 The low temperature central fresh water return header temperature. The low temperature central fresh water cooler outlet temperature. The low temperature central fresh water supply header temperature. The low temperature central fresh water cooler inlet temperature. Cooling Systems
C According to the illustrated diesel engine cooling water systems diagram, what is the functional description of the low temperature central fresh water thermostat? Illustration MO-0129 The thermostat is a two-way valve set up to throttle the flow bypassing around the central fresh water cooler. The thermostat is a two-way valve set up to throttle the flow through the central fresh water cooler. The thermostat is a three-way valve set up as a mixer proportioning flow through and around the central fresh water cooler. The thermostat is a three-way valve set up as a diverter proportioning flow through and around the central fresh water cooler. Cooling Systems
B If the cooling water temperature and the lube oil temperature in a diesel engine are too high, the cause can be __________. a dirty lube oil strainer excessive wear of the cooling water pump an oil suction line restriction internal water leaks Diesel Engine Principles 
B If the raw water supply pressure for a diesel engine cooling system is below normal, you should check for a __________. cracked head clogged sea strainer broken thermostat blown head gasket Diesel Engine Principles 
B Antifreeze solutions containing ethylene glycol should not be mixed with corrosion protection oils, as the resultant mixture __________. is dangerously flammable may cause frothing has a higher chloride content promotes scale buildup Diesel Engine Principles 
D In a closed cooling water system, which of the following problems can cause the water pressure to fluctuate? An open vent in the cooling system. A restricted water passage in the engine. A fouled sea chest. Air entrained in the cooling water. Diesel Engine Principles 
A When a leak has developed in the lube oil cooler of an operating diesel engine, which of the listed operating conditions can be expected to occur? Lube oil level decreases Lube oil level increases Lube oil contaminated with fresh water coolant Lube oil contaminated with saltwater Diesel Engine Principles 
B On small diesel engines, a noticeable decrease in the time interval between the replacement of the lube filter cartridge indicates __________. excessive oil temperature piston ring blow-by excessive oil pressure dirty air filter Diesel Engine Principles 
D Scale and dirt accumulation in the waterside of a lube oil cooler will be indicated by a gradual increase in the lube oil __________. foaming viscosity TBN number temperature Diesel Engine Principles 
A How is the illustrated strainer element cleaned during engine operation? Illustration MO-0057 The T-handle is rotated. The housing is removed and the element is cleaned with a solvent. The drain plug is removed and the housing is drained. The strainer element is removed, cleaned in kerosene or solvent, and dried with an air brush. Diesel Engine Principles 
B In a normally operating diesel engine, the main source of lubricating oil contamination in the crankcase is a result of the __________. air when no air cleaners are used combustion byproducts removed from the cylinder walls condensation of water vapors metal particles loosened by wear Diesel Engine Principles 
D A dirty diesel engine oil filter element can best be detected by __________. visual inspection of the elements high lube oil sump temperature decrease in oil viscosity from the filter the pressure drop across the filter Diesel Engine Principles 
B The color of the diesel engine detergent type lube oil in an operating diesel engine is black, this indicates __________. water dilution normal oil condition fuel dilution worn out' oil Diesel Engine Principles 
C A dirty lube oil strainer can result in __________. crankcase dilution low lube oil temperature low bearing oil pressure excessive oil consumption Diesel Engine Principles 
B In an operating diesel engine, pre-ignition can be caused by __________. excessively late fuel injection oil in the air charge water in the fuel injection continuing after the fuel charge is ignited Diesel Engine Principles 
D Irregular engine speed in a diesel generator can be caused by __________. high generator load low fuel viscosity high injection pressure binding in the fuel control linkage Diesel Engine Principles 
B If fuel oil were being discharged from the waste water outlet of a fuel oil disk type centrifuge, operated as a separator, you should __________. remove the discharge ring reprime the purifier with sealing water slow the centrifuge to its proper speed install an additional discharge ring Diesel Engine Principles 
D A modern centrifuge, similar to the device shown in the illustration, is opened for periodic cleaning. The most common cause of operating failure after reassembling, is due to __________. Illustration MO-0012 low drive motor RPM excessive back pressure in the bowl and fuel oil break over the failure of the opening and closing water supply not replacing the bowl O-rings that have taken a permanent set Diesel Engine Principles 
B Heat damage to fuel injection nozzles can be prevented by avoiding __________. excessive fuel oil temperature long periods of engine overload metallic contact between nozzles and cylinder heads hard carbon deposit and varnish on the nozzles Diesel Engine Principles 
A One cause of diesel engine surging can be a result of __________. injection pump fuel rack binding or sticking low compression solenoid stuck open fuel booster pump pressure too high Diesel Engine Principles 
A Which of the following problems can occur if you continually fail to drain off condensate from a starting air receiver? Corrosion and eventual failure of the tank. Gumming of the tank relief valves. Immediate failure of components downstream of the compressed air system. Boiling of the water oil mixture as pressure is reduced. Diesel Engine Principles 
A On a diesel engine with direct-cylinder admission air starting, a leaking air starting valve would be indicated by __________. an overheated starting air supply pipe excessive smoke from the engine exhaust carbon deposit on the exhaust valves early fuel ignition Diesel Engine Principles 
B Which of the following conditions is most likely to occur if the electric starter motor pinion gear fails to disengage from the flywheel of a diesel engine after the engine has started? Engine will stop Starting motor will dangerously over speed Flywheel will be damaged Combustion gases will enter the air starting system Diesel Engine Principles 
C When starting air is admitted, a diesel engine turns over very slowly without firing. The cause may be __________. an obstruction in an engine cylinder water accumulation in some engine cylinders low starting air pressure low scavenge air pressure Diesel Engine Principles 
B When an additional load is applied to a diesel engine which is using an inadequately inflated air bladder clutch unit, you can expect __________. pneumatic seizure overheating because of slipping shoes chipped reduction gear teeth excessive wear on the thrust bearings Diesel Engine Principles 
B Misalignment of the drive shaft and propeller shaft flanges can be detected by using a dial indicator or __________. inside micrometer feeler gage adjustable trammel sighting device Diesel Engine Principles 
B One of the most common causes of reduction gear failure is gear wear caused by scoring as a result of __________. surface fatigue of the gears an inadequate lube oil film plastic flow of the gears fretting corrosion from water contamination Diesel Engine Principles 
A In a diesel engine, a leaking exhaust valve can cause __________. misfiring preignition interrupted scavenging reduced scavenging Diesel Engine Principles 
B A dry-type exhaust silencer clogged with soot, will cause __________. low exhaust temperature loss of engine power burned intake valves engine racing Diesel Engine Principles 
D White smoke exhausting from a diesel engine can result from __________. high exhaust temperature high lube oil temperature low turbocharger speed low cooling water temperature Diesel Engine Principles 
C Black smoke exhausting from an operating diesel engine is an indication of poor combustion which may be caused by __________. water in the fuel insufficient fuel for combustion clogged air intake passages burning lubricating oil Diesel Engine Principles 
A A diesel engine may be hard to start if the __________. air intake is restricted engine is cranked too fast vibration dampener is faulty exhaust back pressure is low Diesel Engine Principles 
B Which of the following conditions is indicated by the presence of water in the scavenging air receiver? Leaking cylinder head gaskets Leaking after cooler
Excessively high scavenge air temperature
Auxiliary blower failure Diesel Engine Principles 
D Excessive mechanical and pulsating vibrations developed in a main propulsion diesel engine may be more likely to cause damage to an attached __________. scavenged air pump because it is designed for steady state operation rather than pulsating gas load
reciprocating scavenge pump because of its direct linkage to the crankshaft
centrifugal cooling water pump because of the close tolerances required between the impeller rim and the volute gas driven turbocharger because it has a wide speed range, high operating temperatures and close tolerances. Diesel Engine Principles 
C Maintaining the lowest possible scavenging air temperature at all times is not recommended due to the possibility of the __________. air charge density becoming too high piston crown surfaces becoming too cold formation of excessive quantities of condensate compression pressure being greatly reduced Diesel Engine Principles 
C The power output of a turbo-charged diesel engine will drop if the cooling water flow through the after cooler is interrupted because the __________. turbocharger stalls exhaust pressure increases air charge density decreases scavenge effect increases Diesel Engine Principles 
D Which condition indicates the air side fouling of an aftercooler on a turbocharged diesel engine? An increased air temperature differential between the cooler inlet and outlet. A decrease in the air pressure differential across the cooler. Excessive condensate forming in the air box. A decrease in the air temperature differential between the cooler inlet and outlet. Diesel Engine Principles 
C Which of the following problems can cause an above normal air temperature to develop in the intake manifold of a turbocharged and after cooled diesel engine? Faulty turbocharger turbine diffuser ring Faulty turbocharger compressor ring Insufficient cooling water flow to the after coolers Clogged air intake filters Diesel Engine Principles 
A An operating diesel engine that suddenly loses power, is due to a/an __________. restricted turbocharger air intake oil leak into the turbocharger dribbling injector low fuel viscosity Diesel Engine Principles 
D Corrosion and grooving on the blading of an exhaust driven turbocharger is caused by certain components of residual fuel oils. These components are vanadium, sodium, and __________. copper carbon hydrogen sulfur Diesel Engine Principles 
A A sudden power loss from a turbocharged and aftercooled diesel engine is an indication of a/an __________. turbocharger malfunction or failure crankcase exhauster overload overload on the intercooler obstruction in the engine cylinders Diesel Engine Principles 
D A thin film of oil on the lobes of a Roots-type blower indicates __________. proper lubrication
timing out of adjustment excessive cylinder lubrication leaking rotor bearing oil seals Diesel Engine Principles 
C The theoretical minimum compression ratio necessary to ensure compression ignition in a direct injection diesel engine is __________. 18:1 10:1 12:1 8:1 Diesel Engine Principles 
D If the compression ratio is increased on any diesel engine, __________. the expansion ratio will decrease combustion will be slowed down thermal efficiency will decrease thermal efficiency will increase Diesel Engine Principles 
B The most important factor in engine performance is the actual power output at the end of the crankshaft available for doing work. This is known as __________. indicated horsepower brake horsepower net horsepower friction horsepower Diesel Engine Principles 
A Which of the following relationships exist between the temperature developed in a combustion space, and the compression ratio of the engine? Higher compression ratios create higher temperatures. Higher temperatures create higher compression ratios. Lower temperatures create higher compression ratios. Higher compression ratios create lower temperatures. Diesel Engine Principles 
B Which of the following reasons represents why the designed compression ratio of a gasoline engine is lower than that of a diesel engine? Compression must be low for smooth operation. The heat of compression is not used as an ignition source of the fuel. Compression must be low to have effective preignition. Compression must be low for effective spark ignition. Diesel Engine Principles 
B In the starting process of a diesel engine, the main object is to attain the compression conditions sufficient to __________. turn the flywheel ignite the fuel reduce friction overcome inertia Diesel Engine Principles 
A The thermal energy produced by an internal combustion engine is transformed into __________. mechanical energy external energy internal energy combustion energy Diesel Engine Principles 
C Diesel engines are classified as reciprocating internal combustion engines because they __________. burn fuel in a combustion chamber that moves back and forth use a continuous combustion process to impart rotary motion to the Pistons burn fuel in a closed chamber which imparts linear motion to Pistons use energy from fuel burned outside their cylinders Diesel Engine Principles 
C The highest pressure in a diesel engine cylinder normally occurs __________. at TDC before TDC after TDC during air starting Diesel Engine Principles 
A The load is always placed on the lower half of the main bearings in a/an __________. two-stroke/cycle engine four-stroke/cycle engine reverse cycle engine double acting engine Diesel Engine Principles 
B Which of the terms listed below represents the operational speed at which excessive engine vibration is created? Non-harmonic speed. Critical speed. Maximum speed. Design maximum speed. Diesel Engine Principles 
D The cubic inch (or liter) displacement of a cylinder is determined by the diameter of the piston and the __________. length of the crankshaft volume of the clearance space weight of the piston length of the stroke Diesel Engine Principles 
C Which of the following is an example of a solid bearing? Turbo-generator turbine bearing Thrust bearing Piston pin bushing Spring bearing Diesel Engine Principles 
C The proper location for journal bearing oil grooves is __________. halfway between bottom and where shells meet at the bottom of the bearing as a side relief where the two shells meet in the region of the load bearing surface Diesel Engine Principles 
B Which of the bearings listed below is most widely used for the main and connecting rod bearings of a modern high-speed diesel engine? Poured Babbitt, self-aligning Precision insert Steel-lined Split roller Diesel Engine Principles 
C The linear motion of a diesel engine piston is converted into the rotary motion required to drive gears, propeller shafts, and generators by the __________. journal bearings camshaft crankshaft flywheel Diesel Engine Principles 
D Connecting rods in a diesel engine are used to connect the __________. crankshaft to the gear train rocker arm to the camshaft engine to the bed piston to the crankshaft Diesel Engine Principles 
D Component 'U' of the diesel engine shown in the illustration is called the __________. Illustration MO-0122 frame stiffener main bearing support assembly frequency tuner crankshaft counterweight Diesel Engine Principles 
C The diesel engine component labeled "3", shown in the illustration is called the __________. Illustration MO-0122 scavenging air space cylinder liner cylinder head head valve assembly Diesel Engine Principles 
B In the illustrated diesel engine, which label points to the piston? Illustration MO-0122 6 4 3 K Diesel Engine Principles 
B The diesel engine wrist pin in the illustration is indicated by the component labeled __________. Illustration MO-0122 "G" "7" "17" "S" Diesel Engine Principles 
B A normally operating diesel engine is shutdown by __________. over speeding the engine securing the fuel supply shutting off the air supply securing the ignition system Diesel Engine Principles 
B Before starting a diesel engine, you should always __________. clean the air filter check the crankcase oil level change the fuel oil strainers check the pyrometer readings Diesel Engine Principles 
A Which of the listed diesel engine operating conditions should be checked immediately after any diesel engine is started? Lube oil pressure Exhaust temperature Lube oil level Water level in the expansion tank Diesel Engine Principles 
D When attempting to restart a warm high-speed engine, which of the following reactions can you expect? Excessive fuel use Higher than normal lube oil pressure Longer starting periods Higher than normal temperatures for start up Diesel Engine Principles 
B Before starting a diesel engine that has an engine driven lube oil pump, you should __________. top off the expansion tank pressurize the lube oil system with the pre-lube pump open the bypass line cut in the lube oil cooler Diesel Engine Principles 
A Babbitt is a metal alloy commonly used for lining __________. precision bearings shim stock valve seats saltwater piping Drive Systems
c When checking a water-lubricated stern tube bearing while underway, what should be checked for? Ensure that the stuffing box packing gland is loose enough so that the last ring of packing is visible. Ensure that the stuffing box packing gland is tight enough so that there is no leakoff
whatsoever.
Ensure that the stuffing box packing gland is taken up just enough so that the leakoff rate is a periodic drip. Ensure that the stuffing box packing gland is loose enough so that there is a steady stream of water leaking by. Drive Systems
B Which of the following methods is used to securely fasten the Babbitt lining of a reduction gear bearing to its shell? The Babbitt has a crescent shaped pocket cast symmetrically about the bearing split. The Babbitt is centrifugally spun into the bearings or cast under a pressure head. The Babbitt is securely bonded to the shell by the pressure of the hydrodynamic oil wedge. The Babbitt is relieved in way of the split and held in place by locking pins. Drive Systems
D As found in a reduction gear drive system, thrust bearings serve to __________. hold the main engine in place increase the shaft speed limit the radial movement of the shaft transmit the force produced by the propeller to the structure of the ship Drive Systems
B By what means are two sections of propulsion line shafting typically joined together? By the use of a sleeve or clamp type solid coupling By the use of a flange type solid coupling By the use of a chain type flexible coupling By the use of a gear type flexible coupling Drive Systems
B In addition to checking the lube oil sump level and temperature of a line shaft steady bearing, what else must be checked for? Ensure flow through the gravity head tank overflow sight glass. Ensure free rotation of the oiling ring with the shaft. Ensure that the oiling ring does not rotate with the shaft. Ensure adequate lube oil pump discharge pressure. Drive Systems
C What is the primary purpose of self-aligning spherically-seated line shaft bearings? To compensate for torsional twisting of the shaft in response to torque variations. To compensate for variations in propeller thrust loading in response to load changes. To compensate for flexing of the hull in response to different loading conditions. To compensate for propeller induced vibrations as a result of propeller irregularities. Drive Systems
D What statement is true concerning oil-lubricated stern tube bearings? The forward and after seals are both designed to prevent the ingress of sea water and the after seal is designed to retain the lubricating oil within the bearing. The forward and after seals are both designed to prevent the ingress of sea water and the forward seal is designed to retain the lubricating oil within the bearing. The forward and after seals are both designed to retain the lubricating oil within the bearings and the forward seal is designed to prevent the ingress of sea water. The forward and after seals are both designed to retain the lubricating oil within the bearings and the after seal is designed to prevent the ingress of sea water. Drive Systems
D Which of the devices listed is commonly used to compensate for the expansion and minor misalignments occurring between the main turbine rotor and the reduction gear? Quill shaft Expansion gear Sliding sleeve  Gear-type flexible coupling Drive Systems
A Hydraulic couplings will transmit torque equal to the input torque by means of energy changes in a rotating vortex of liquid. For the vortices to form there must be __________. slip between the impeller and runner
less than 2 per cent slip between the impeller and runner
axial thrust generated by the runner pinion shaft
momentary torsional vibration transmitted by the driving impeller Drive Systems
C The pinion gear shown in the illustration, is located __________. Illustration MO-0086 below "2" and "4" between "2" and "4" between "1" and "3" below "1" and "3" Drive Systems
A One advantage of electromagnetic slip couplings is __________. torsional vibrations are reduced
torque increases with a decrease in excitation current
the coupling rapidly responds to sudden changes of load
excitation and induction power losses appear as a change in torque instead of rotational speed between the primary and secondary elements Drive Systems
A What type of clutch is used in the illustrated medium-speed diesel engine reduction gear? Illustration MO-0085 Pneumatic  Mechanical Electromagnetic Hydraulic Drive Systems
B What type of clutch is pictured in the illustration? Illustration MO-0089 Mechanical Hydraulic Electromagnetic Pneumatic Drive Systems
A Which of the following methods is used to lubricate main propulsion medium-speed diesel engine reduction gears? Oil is sprayed through nozzles at the point of gear mesh. Oil rings in channels outside the gears dip into oil in the sump and carry it to the gear teeth. The gears run through an open oil sump and oil is carried along on the gear teeth. Oil is pressure fed through internal drilled passages which force oil to the gear's periphery. Drive Systems
C The purpose of the main diesel engine reduction gears is to __________. transmit vibration and thrust to the ship's hull provide a means of reversing the main diesel engines in an emergency reduce high diesel engine RPM to an efficient propeller RPM reduce engine room noise levels during high-speed operations Drive Systems
B The component shown in the illustration, labeled "I", is the __________. Illustration SE-0013 first reduction pinion first reduction gear second reduction gear second reduction pinion Drive Systems
C What type of reduction gear would most commonly be used with twin medium-speed propulsion diesel engines driving a single shaft? Single reduction, planetary Single reduction, single input Single reduction, double input
 o
Double reduction, double input, articulated Drive Systems
B Reduction gear casings are vented in order to __________. allow windage to exist for cooling the gears avoid a buildup of pressure within the gear case
minimize lube oil foaming within the case
allow for axial clearance between the gears Drive Systems
B In addition to achieving a speed reduction for efficient propeller operation, what statement represents other possible functional purposes for reduction gears? Reduction gears can be used for engine rotation reversal and reduction gears can be used for multiple propeller shaft outputs. Reduction gears can be used for propeller thrust reversal and reduction gears can be used for multiple prime mover inputs. Reduction gears can be used for propeller thrust reversal and reduction gears can be used for
multiple propeller shaft outputs.
Reduction gears can be used for engine rotation reversal and reduction gears can be used for
multiple prime mover inputs.
Drive Systems
D What would be the most accurate description of the illustrated cutaway drawing of a reduction gear as used for medium-speed diesel propulsion? Illustration MO-0085 Single input, single reduction, non-reversing gear Single input, double reduction, non-reversing gear Single input, double reduction, reversing gear Single input, single reduction, reversing gear Drive Systems
A Which of the statements represents a characteristic of the thrust collar in a Kingsbury thrust bearing? It turns with the shaft and the pivot shoes do not rotate.
It is stationary and the shoes turn with the shaft.
It is turned by the base ring of the bearing.
It is held in position by the bearing base ring. Drive Systems
A The bearing shown in the illustration is designed to carry thrust when applied __________. Illustration MO-0001 right to left only the bearing pictured is not designed to carry thrust in either direction left to right only Drive Systems
B What is the function of the main thrust bearing? Prevents lateral movement of the slow speed gear. Transmits propeller thrust to the hull. Keeps spring bearings in line. Prevents main reduction gear axial movement. Drive Systems
A Kingsbury thrust bearings are lubricated by __________. flooding the thrust bearing assembly with oil submerging oil wiper rings in an oil bath pressure lubricating through internal passages spraying oil directly on the thrust collar and shoes Drive Systems
B On a large diesel engine installation, crankshaft axial alignment is maintained by the __________. piston rod guides engine thrust bearing crosshead bearing main shaft flexible coupling Drive Systems
C With a direct drive main propulsion arrangement, what statement is true? The engine to propeller shaft speed ratio is variable. The engine speed is greater than the propeller shaft speed. The engine speed is equal to the propeller shaft speed. The engine speed is lower than the propeller shaft speed. Drive Systems
C When a slow-speed diesel engine is used to directly drive a fixed-pitch propeller, how is a stop order met? Both the ahead and astern clutches must be disengaged. The propulsion clutch must be disengaged. The engine itself must be stopped.  The propeller must be brought to zero pitch. Drive Systems
C What type of propeller thrust reversing method (or methods) is or are used with a main propulsion slow-speed crosshead type diesel engine installation? A non-reversing engine driving a fixed-pitch propeller is the only method used. A reversing engine driving a controllable-pitch propeller is the only method used. Either a reversible engine driving a fixed-pitch propeller or a non-reversible engine driving a controllable-pitch propeller could be used.  Either a reversible engine driving a controllable-pitch propeller or a non-reversible engine driving a fixed-pitch propeller could be used. Drive Systems
D Diesel engines powering large vessels that drive fixed-pitch propellers through a nonreversing reduction gear are of what type? Medium-speed, non-reversing engines Slow-speed, reversing engines Slow-speed, non-reversing engines  Medium-speed, reversing engines Drive Systems
D Fuel is admitted to a diesel engine cylinder through the __________. intake valves carburetor exhaust ports injector nozzles Fuel Service Systems
C Fuel injection systems are designed to primarily meter fuel, atomize fuel, and __________. create turbulence in the combustion chamber aid in completing cylinder scavenging inject fuel at the proper time minimize fuel penetration into the cylinder Fuel Service Systems
D Movement of the pump control rack in a fuel injection system using individual plunger-type pumps __________. varies the compression of the delivery valve spring changes the length of the pump stroke changes the position of the fuel inlet ports varies the quantity of fuel delivered Fuel Service Systems
B Fuel oil discharged into the diesel engine cylinder is atomized at the __________. turbocharger injector nozzle tip carburetor fuel oil pump Fuel Service Systems
B The illustrated device is operated directly by __________. Illustration MO-0041 a rocker arm and push rod fuel oil pressure cam action excessively high combustion pressure Fuel Service Systems
A The main advantage of unit injectors over other fuel injection systems is __________. the lack of high pressure fuel lines their relatively low injection pressures reduced wear of spray orifices the lessened chance of fuel leaks into the engine sump Fuel Service Systems
D Injection pressure in a common rail fuel system is controlled by __________. engine speed varying the fuel pump piston stroke varying the injector needle valve clearance a bypass valve Fuel Service Systems
B Fuel injection pumps using the port and helix metering principle requires the use of a __________. crosshatched design lapped plunger and barrel variable stroke variable cam lift Fuel Service Systems
C Which of the fuel injection systems listed uses a spring loaded differential spray needle valve and an individual pump for each cylinder? Common-rail injection Air injection Jerk pump injection Distributor injection Fuel Service Systems
C The amount of fuel delivered by a helical plunger fuel injection pump is controlled by __________. varying the pump discharge pressure varying the pump return pressure rotation of the pump plunger rotation of the pump barrel Fuel Service Systems
A In what location is heavy fuel oil kept below the flash point? Heavy fuel oil settling and day tanks  Heavy fuel oil mixing tank Heavy fuel oil purifier heater outlet Heavy fuel oil final heater outlet Fuel Service Systems
C In what location is heavy fuel oil kept above the flash point, but below the boiling point of water? Heavy fuel oil settling and day tanks Heavy fuel oil mixing tank Heavy fuel oil final heater outlet Heavy fuel oil purifier heater outlet Fuel Service Systems
C In an HFO service system, what is the immediate destination of the fuel unconsumed by the main propulsion diesel engine? The unconsumed fuel is recirculated back to the fuel injection pumps suction. The unconsumed fuel is recirculated back to the settling tank. The unconsumed fuel is recirculated back to the mixing tank (if fitted) or to the day tank. The unconsumed fuel is recirculated back to the booster pump suction. Fuel Service Systems
A Which of the listed substances can be satisfactorily removed from diesel fuel by centrifuging? Sludge Gasoline Fuel oil Lube oil Fuel Service Systems
B Whether using a centrifuge or a simple filter, oil cleaning and filtration will be the most effective when the oil is at a __________. high temperature and a high viscosity high temperature and a low viscosity low temperature and a high viscosity low temperature and a low viscosity Fuel Service Systems
B When monitoring a heavy fuel oil treatment plant, what would be an indication that the treatment plant throughput volume is less than the main engine consumption? The HFO settling tank will continuously drop in level. The HFO day tank will continuously drop in level. The HFO day tank will rise and eventually overflow into the HFO settling tank. The HFO settling tank will rise and eventually overflow into the HFO day tank. Fuel Service Systems
D According to the illustrated diesel engine fuel treatment and fuel service systems schematic, what would be the appropriate valve configuration for operating the two heavy fuel oil purifiers in series? Illustration MO-0077 Valves 2, 3, and 6 all OPEN Valves 2, 3, and 6 all CLOSED Valves 2 and 3 OPEN, and Valve 6 CLOSED Valves 2 and 3 CLOSED, and Valve 6 OPEN Fuel Service Systems
A According to the illustrated diesel engine fuel treatment and fuel service systems schematic, what statement is true concerning the valves labeled "4" and "5"? Illustration MO-0077 Valves 4 and 5 are closed during normal operation, but when opened will allow one of the HFO purifiers to be used as a backup DO purifier, should the DO purifier become disabled. Valves 4 and 5 are closed during normal operation, but when opened will allow the DO purifier to be used as a backup HFO purifier, should one of the HFO purifiers become disabled. Valves 4 and 5 are closed during normal operation, but when opened will allow all three purifiers to centrifuge HFO while in series. Valves 4 and 5 are closed during normal operation, but when opened will allow all three purifiers to centrifuge HFO while in parallel. Fuel Service Systems
A Valve '1', as shown in the illustration when, should be operated when __________. Illustration MO-0077 entering or departing port. starting auxiliary boilers. viscosimeter 'V' measures low viscosity. mixing tank is 'full'. Fuel Service Systems
D To minimize corrosion, fuel oil strainer disks, spacers and scraper blades are made of __________. brass copper iron monel metal or stainless steel Fuel Service Systems
A For a continuous operation diesel engine, a duplex filter unit would be the best arrangement because __________. changing filter elements would not interrupt engine operation filtering occurs twice in each pass of oil through the system clogging will not occur dropping pressure is half of that through a single filter unit Fuel Service Systems
C According to the illustrated diesel engine fuel treatment and fuel service systems schematic, what is the purpose of the valve labeled "1"? Illustration MO-0077 HFO/DO fuel mixing valve for main engine HFO/DO fuel changeover valve for auxiliary engines (and boiler) HFO/DO fuel changeover valve for main engine HFO/DO fuel mixing valve for auxiliary engines (and boiler) Fuel Service Systems
B What would be the primary indication that a heavy fuel oil purifier supply pump suction strainer needed cleaning? An increase in fuel oil supply temperature to the bowl. An increased pressure drop across the strainer (more differential). A decreased pressure drop across the strainer (less differential). A drop in purifier bowl speed. Fuel Service Systems
B What would be the primary indication that a fuel oil service system booster pump duplex suction strainer needed to be shifted over and cleaned? A decreased pressure drop across the strainer element on service (less differential). An increased pressure drop across the strainer on service (more differential). A drop in fuel oil service system booster pump rotational speed. An increase in fuel oil service system booster pump discharge pressure. Fuel Service Systems
D Cooling the intake air supplied to a diesel engine will __________. reduce mean effective pressure decrease average compression ratio decrease air charge density increase peak power output Intake and Exhaust Systems
C A large, low-speed, main propulsion diesel engine uses sea water to directly cool the __________. cylinder heads exhaust valves scavenging air injectors Intake and Exhaust Systems
C An increase in the air inlet manifold pressure of a diesel engine will result in a/an __________. decrease in maximum cylinder pressure increase in ignition lag decrease in fuel consumption per horsepower-hour decrease in exhaust manifold pressure Intake and Exhaust Systems
B In a naturally aspirated diesel engine, the volume of air intake is directly associated with engine __________. compression ratio displacement fuel pressure cylinder clearance volume Intake and Exhaust Systems
C What is the function of the intake system for a diesel engine? The intake system's function is to ensure an adequate supply of clean lubricating oil to support engine lubrication. The intake system's function is to ensure an adequate supply of clean sea water to support engine cooling. The intake system's function is to ensure an adequate supply of clean air to support engine combustion and scavenging. The intake system's function is to ensure an adequate supply of clean air to support engine crankcase ventilation. Intake and Exhaust Systems
D What is the function of the after coolers installed in the diesel engine air intake system? Decrease the air density Increase the exhaust temperature Decrease the lube oil temperature Increase the air density Intake and Exhaust Systems
C The section of the turbocharger which would be connected to the aftercooler inlet is labeled __________. Illustration MO-0080 C H B K Intake and Exhaust Systems
A Compared to a naturally aspirated diesel engine, a supercharged diesel engine has __________. a cylinder air charge of higher pressure reduced cylinder mean effective pressure less valve overlap reduced blow-by Intake and Exhaust Systems
A A naturally aspirated diesel engine at full throttle will have an intake manifold pressure __________. slightly less than atmospheric pressure approximately equal to exhaust manifold pressure at all times that is widely fluctuating constantly decreasing as engine load increases Intake and Exhaust Systems
D The most common instrument used to measure diesel engine exhaust pressure is the __________. pyrometer bourdon gauge pneumercator manometer Intake and Exhaust Systems
B In a diesel engine exhaust system, the cooling of the exhaust gases below their dew point, will result in __________. increased engine back pressure sulfuric acid corrosion surface pitting of the turbocharger compressor blades moisture impingement on the turbocharger compressor blading Intake and Exhaust Systems
B One of the factors limiting the amount of load which can be put on a modern marine diesel engine is the __________. governor sensitivity exhaust temperature fuel injection pressure speed of the cam shaft Intake and Exhaust Systems
C Exhaust pipes for separate main propulsion diesel engines can be combined only when __________. space limitations prevent separately run pipes the engines are small auxiliary units they are arranged to prevent gas backflow to each engine a waste heat boiler is installed Intake and Exhaust Systems
B The exhaust system for a turbocharged diesel engine functions to __________. power the after coolers power the turbocharger reduce the cylinder scavenge effect cool the turbocharger Intake and Exhaust Systems
D The lube oil strainer shown in the illustration is used on the reduction gear of a mid-size diesel engine. The strainer elements consist of __________. Illustration MO-0057 fibrous braid wire mesh pleated paper metal disks Lubrication Systems
D Lube oil cannot be efficiently filtered if it's __________. pump capacity is greater than the system's needs viscosity is too low pump discharge pressure is higher than the system's pressure temperature is too low Lubrication Systems
A A magnetic strainer is primarily used in diesel engine reduction gear oil systems to remove small particles of __________. ferrous materials Babbitt copper acidic materials Lubrication Systems
A Where would a coarse screen wire-mesh strainer normally be found on a diesel engine lubrication system? pump suction line filter bypass return line pump discharge line gravity tank inlet line Lubrication Systems
A Which of the following statements is true concerning a main diesel engine oil cooler? The oil pressure is greater than the cooling water pressure. The oil flow control valve is always installed in the oil input line. The oil temperature is less than the cooling water temperature. The oil pressure is less than the cooling water pressure. Lubrication Systems
A The lube oil cooler is located after the lube oil filter in order for __________. the filter to operate more efficiently galvanic action in the cooler to be minimized positive lube oil pump suction to be assured the lube oil cooler to be bypassed Lubrication Systems
A Heat exchangers are most commonly found in a small auxiliary diesel engine __________. lube oil system governing system air starting system fuel oil system Lubrication Systems
A The purpose of an oil mist detector in a main propulsion diesel engine is to warn of __________. a possible overheated bearing excessive carbon buildup in the lube oil low cylinder oil pressure excessively high crankcase vacuum Lubrication Systems
A Which of the following problems could develop due to the accumulation of oil vapors in the crankcase of a diesel engine? Crankcase explosion Poor fuel economy Reduced lubrication Combustion knock Lubrication Systems
B The possibility of a diesel engine crankcase explosion will be increased by operating an engine __________. with a crankcase vacuum between 1.5" and 2" of water with a leaking crankcase inspection cover gasket equipped with a crankcase exhaust blower which vents to fresh air in cooler sea water temperatures Lubrication Systems
A If a diesel engine has been stopped because of piston seizure due to severe overheating, the crankcase __________. inspection covers should not be opened until the engine has cooled scavenge pump should be immediately secured to prevent loss of lube oil ventilation system should be continued in operation for one hour for cooling explosion covers should be opened slightly to provide extra ventilation Lubrication Systems
B Which of the following methods is normally used to lubricate bearings in a small high-speed diesel engine? Splash lubrication Pressure lubrication Sight feed lubricators Mechanical lubricators Lubrication Systems
B In an auxiliary diesel engine "by-pass type" lubricating oil system, the main lube oil pump forces __________. all of the oil used by the engine through a filter some of the oil used by the engine through a filter some of the oil used by the engine through a centrifuge all of the oil used by the engine through a centrifuge Lubrication Systems
D Lubrication for the main reduction gears used with diesel engines is usually supplied by __________. oil from the main engine sump the stern bearing head tank the stern bearing sump tank an independent lube oil system Lubrication Systems
D Lube oil pumps taking suction from the sump of most small marine engines are usually __________. diaphragm type eductor type centrifugal type positive displacement type Lubrication Systems
A Which of the routine maintenance procedures listed is required for starting air receivers? Frequent draining of accumulated moisture. Frequent testing of relief valves. A close watch on temperature to prevent fluctuations in pressure. Frequent cleaning to remove oil and foreign matter. Starting Systems
B Starting air check valves are held firmly on their seats by __________. cam rollers on the camshaft spring force air pressure on top of the valve differential piston air pressure on the bottom of the valve differential piston Starting Systems
D A two-stroke/cycle diesel engine requires less starting air than a four-stroke/cycle diesel engine, of equal displacement, because the two-stroke/cycle diesel engine __________. has little or no internal friction has a lower effective compression ratio operates with scavenge air under a positive pressure operates without energy absorbing intake and exhaust strokes Starting Systems
B Where is the air charge for an air starting system stored? Air compressor Pressurized tank Distributor assembly Cylinder check valve Starting Systems
D An accumulator used in a hydraulic starting system is generally located between the __________. pump and the compressor storage tank and the pump starting motor and the reserve tank pump and the starting motor Starting Systems
C For a diesel engine, approximately how long can an electric starter motor be operated continuously before damage may begin to occur due to overheating? Overheating the motor cannot occur. Not more than 90 seconds Not more than 30 seconds Not more than 60 seconds Starting Systems
A Auxiliary diesel engine electric starting motors use __________. battery power direct current 400 cycle per second motor-generator power alternating current transformers low amperage, high voltage AC power Starting Systems
B Diesel engine electric starting motors generally require heavier duty motors and operate at higher voltages than comparable starting motors for gasoline engines due to __________. flywheel effect higher compression pressures lower starting temperatures higher speed required Starting Systems
A Air motors used for starting some auxiliary diesel engines are generally the type known as a/an __________. vane motors accumulator motors plunger motors gear motors Starting Systems
D Hydraulic starters are installed on many lifeboat diesel engines instead of comparable air start systems, because __________. hydraulic starters are the least expensive of all starting systems the system does not require high pressure piping hydraulic systems turn diesel engines at higher rates of speed than air starters the system can be manually recharged Starting Systems
B When an engine fitted with a hydraulic starting system starts up, the starter is protected from the higher speed of the engine by __________. the immediate increase in hydraulic pressure the overrunning clutch closing the starting check valves the pivoting of the shaft from being engaged with the flywheel Starting Systems
A The purpose of the engine-driven hydraulic pump in an auxiliary diesel engine hydraulic starting system is to __________. restore hydraulic pressure in the accumulator after starting engage the starter motor with the flywheel fill the sump and prevent low level in the system bypass the hydraulic motor when the engine is running Starting Systems
D A Bendix drive starting motor disengages the drive gear from the flywheel by __________. applying accumulator pressure spring force rotating of the starting cam having the flywheel impart a torque to the starter pinion Starting Systems
D The pinion of an auxiliary diesel electric starting motor normally engages the flywheel ring gear by means of a/an __________. magnetic type coupling automatic follow-up muff coupling and release Bendix drive or similar mechanism Starting Systems
D Auxiliary diesel engine electric starting motors use __________. low amperage, high voltage AC power alternating current transformers 400 cycle per second motor-generator power battery power direct current Starting Systems
C Starting systems for large, direct reversing, main propulsion diesel engines are usually __________. hydraulic starting motor electric starting motor direct air admission vane type air motors Starting Systems
A During the starting of a diesel engine, compression gases are prevented from backing into the air starting system, shown in the illustration, by the __________. Illustration MO-0046 cylinder air starting check valves high pressure in the starting air manifold air starting control valve individual distribution valves Starting Systems
C When an air started, four-stroke/cycle diesel engine is being cranked over; the starting air is admitted to each cylinder during the beginning of its __________. intake stroke compression stroke power stroke exhaust stroke Starting Systems
D In a medium-speed marine propulsion engine equipped with direct admission air starting valves, the cylinders without air starting valves fire first because the __________. operation is under higher compression fuel is admitted only to these cylinders during cranking compression is released during starting by opening the exhaust valve cylinders are not chilled by the expansion of the starting air Starting Systems
B Auxiliary boilers are divided into several classifications, one of which is __________. water-tube supercritical circulation water-tube forced circulation fire-tube controlled circulation fire-tube express circulation Waste Heat / Auxiliary Boiler
A In a coil-type forced circulation auxiliary water-tube boiler,__________. steam demand response is comparatively rapid steam is recirculated through heating coils in the boiler unevaporated feed water is discharged through the skim tube steam demand response is slow Waste Heat / Auxiliary Boiler
A Which of the following statements concerning fire-tube boilers is correct? Combustion gases flow through the tubes. Flames impinge on the tubes. Combustion occurs in the tubes. Water flows through the tubes. Waste Heat / Auxiliary Boiler
D Bottom blow valves are installed on auxiliary water-tube boilers to __________. completely drain the boiler in an emergency prevent sludge from forming in the steam drum remove floating impurities from the boiler water surface remove settled solids from the water drum Waste Heat / Auxiliary Boiler
A The purpose of try-cocks used on an auxiliary boiler is to __________. provide an alternate means of determining the water level, if the gage glass fails provide a means of adding chemical feed to the boiler water provide a means for blowing down the gage glass act as a steam sentinel valve, if any of the fusible plugs should melt Waste Heat / Auxiliary Boiler
D An exhaust gas bypass is installed on a waste heat boiler in order to __________. bypass exhaust gas at high loads to prevent excessive back pressure
bypass a portion of the exhaust gas at peak loads for better efficiency recycle exhaust gas to the turbocharger minimize moisture condensation in the boiler gas passages at low loads Waste Heat / Auxiliary Boiler
B The maximum pressure developed by a waste heat boiler is determined by the main engine exhaust __________. gas composition gas temperature
pressure
timing Waste Heat / Auxiliary Boiler
D Casing drains may be required on a waste heat boiler gas passage side to __________. prevent an accumulation of boiler water entering gas passages as a result of a pinhole tube leak
 o
as a means to sample stack gases for testing release excess pressure drain off condensation Waste Heat / Auxiliary Boiler
B As shown in the illustration, the function of component "1" is to __________. Illustration MO-0128 condense excess steam produced in the boiler evaporate circulating boiler water into saturated steam
maintain a water level in the steam drum
generate superheated steam to operate the turbo generator Waste Heat / Auxiliary Boiler
D As shown in the illustration, what component would normally be installed at location "D? Illustration MO-0128 Boiler soot blower unit
Boiler water level indicator Flue gas smoke indicator Oil fired mechanical burner Waste Heat / Auxiliary Boiler
A Which of the following statements concerning fire-tube boilers is correct? Combustion gases flow through the tubes. Flames impinge on the tubes. Combustion occurs in the tubes. Water flows through the tubes. Waste Heat / Auxiliary Boiler
D The boiler shown in the illustration would be classed as __________. Illustration MO-0064 forced circulation, coil-type two-pass, water-tube two-pass, scotch marine single-pass, fire-tube, scotch marine Waste Heat / Auxiliary Boiler
B The tube sheets installed in a fire-tube auxiliary boiler are normally connected by __________. girder stays fire-tubes and stay-tubes external boiler plating separate crown sheets Waste Heat / Auxiliary Boiler
B Fusible plugs are installed in fire-tube boilers to __________. provide a means of draining the boiler warn the engineer of low water level cool the crown sheet at high firing rates open the burners' electrical firing circuits Waste Heat / Auxiliary Boiler
D Constant capacity, pressure atomizing, fuel burners designed to meet a wide variation in steaming loads on an auxiliary boiler, are __________. automatically supplied with warmer air on demand automatically supplied with more fuel on demand equipped with standard variable capacity atomize cycled on and off in response to steam demand

Waste Heat / Auxiliary Boiler
C The primary function of a flame safeguard system, as used on an automatically fired auxiliary boiler, is to prevent __________. accidental dry firing and overpressure uncontrolled fires in the furnace explosions in the boiler furna overheating of the pressure parts Waste Heat / Auxiliary Boiler
A A photoelectric cell installed in an automatically fired auxiliary boiler burner management system __________. opens the burner circuit upon sensing a flame failure detects a flame failure by monitoring radiant heat from glowing refractory requires mechanical linkage to secure the burner fuel supply must be bypassed at low firing rates Waste Heat / Auxiliary Boiler
D The pressuretrol which is installed on an auxiliary boiler senses steam pressure changes and __________. controls the flow of feed water to the boiler monitors the boiler high water level secures the fires when a fusible plug burns out automatically regulates the quantity of oil and air flow to the burner Waste Heat / Auxiliary Boiler
B A variable capacity, pressure atomizing, fuel oil burner functions to __________. maintain a constant fuel temperature provide a wide range of combustion provide a constant fuel return pressure maintain smokeless fuel oil atomization Waste Heat / Auxiliary Boiler
C The solenoid valves in the fuel oil supply line to an automatically fired auxiliary boiler, are automatically closed by __________. a decrease in feed temperature high furnace air pressure high steam pressure low steam pressure Waste Heat / Auxiliary Boiler
B Control of the fuel oil metering valve in an automatically fired auxiliary boiler is accomplished by a __________. pressure magnifying device in the steam coil outlet steam pressure sensing device with linkage to the damper air vanes metering device in the air supply line signal from the feed water electrode Waste Heat / Auxiliary Boiler