Assistant Engineer – Limited, Revision & Practice Exams

The minimum temperature requirements for fuel oil in storage tanks is related to the _________.

1. pumpability of the oil ✓
2. size of the containment area in case of overflow
3. fire point of the oil
4. size of the vents

A centrifugal flow gas turbine uses what type of combustion chamber?

1. can ✓
2. annular
3. can-annular
4. double-annular

The longer an oil fire is permitted to burn, the __________.

1. easier it is to control
2. easier it is to extinguish
3. harder it is to extinguish ✓
4. less chance there is of reignition

Before any auxiliary diesel engine hydraulic starting system is opened for servicing or repair, you must __________.

1. Place all control levers in the "HOLD" position
2. Ensure that the hydraulic fluid reservoir is full
3. Block all hydraulic hoses using high-pressure covers
4. Bleed off all hydraulic pressure from the system ✓

Which of the following statements is true concerning the cetane number of diesel fuel?

1. The cetane number affects the amount of injection lag.
2. The cetane number is an indication of the fuel's viscosity.
3. Ignition lag is reduced with fuels having a high cetane number. ✓
4. The cetane number is of little significance in the combustion process.

Compared to a naturally aspirated diesel engine, a supercharged diesel engine has __________.

1. a cylinder air charge of higher pressure ✓
2. reduced cylinder mean effective pressure
3. less valve overlap
4. reduced blow-by

Which of the following conditions could cause the feed pump for an auxiliary boiler to lose suction?

1. Increased suction head pressure
2. Decreased feedwater temperature
3. Pump recirculating line being open too much
4. Excessive feedwater temperature ✓

An auxiliary diesel engine on your vessel has experienced a safety shutdown due to high lubricating oil temperature. What is the appropriate response?

1. Allow the engine to cool off for two minutes, then restart and monitor the lubricating oil temperature to verify the cause of the shutdown.
2. Immediately restart the engine, and monitor the oil temperature to verify the cause of the shutdown.
3. 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. ✓
4. Immediately perform the engine inspections to determine the cause of the high oil temperature safety shutdown.

An open cycle gas turbine engine is best described by which of the following statements?

1. Energy is neither created nor destroyed and the cycle is therefore perpetual.
2. Working fluids are taken in, transformed, and then recuperated.
3. Working fluids are taken in, transformed, and then discarded. ✓
4. Energy is added externally.

How do you manually lockout an SSS clutch?

1. Using the special wrench provided ✓
2. Calculate the engagement speed of the SSS clutch
3. Remove the SSS clutch locking pawls
4. Using air pressure

When conducting a borescope inspection, you must be aware of all of the following factors EXCEPT which?

1. The inspection areas and ports.
2. The limitations of your equipment.
3. The engineer’s experience. ✓
4. The internal reference points.

What is the primary purpose of the diffuser and distributor on the GE LM2500 gas turbine?

1. To provide even temperature distribution at the compressor
2. To provide uniform air flow to the combustor ✓
3. To provide uniform air flow to the turbine
4. To provide uniform air flow to the compressor

Which of the following statements is true concerning the fuel oil ignition system of the gas turbine engine shown in the illustration? Illustration GT-0017

1. The igniters remain energized throughout the normal operation of the engine.
2. The igniters will de-energize when the power turbine exceeds a preset RPM.
3. The igniters will de-energize when the gas generator exceeds a preset RPM. ✓
4. The igniters will only energize if the exhaust gas temperature falls below a preset value.

The wooden shoring shown in the illustration is bearing against the hatch coaming and is supporting a load in the direction indicated by the arrows. Which of the following statements is correct for this condition? Illustration SF-0018

1. Shore "A" will support the greatest load
2. Shore "A" will not slip under load
3. Shore "B" will support the load without it cracking ✓
4. Shore "B" will crack at the pointed end

Which of the gases listed is the poisonous gas most likely to be found in a closed compartment involved in a fire?

1. Nitrogen
2. Hydrogen
3. Carbon dioxide
4. Carbon monoxide ✓

An LNG carrier has an approved type of gas detecting system to detect methane leaks. What area(s) would this be NOT used in?

1. Barrier spaces
2. Boiler burner supply piping
3. Cargo handling rooms
4. Habitability Spaces ✓

During operating periods of a multi-box refrigeration system using a capacity-controlled compressor, when all of the evaporators of a four box plant are actively being fed with liquid refrigerant, the control oil pressure acting on the hydraulic relay piston shown in the illustration will be at what value? Illustration RA-0013

1. the lowest
2. at its mid-range
3. the highest ✓
4. of no consequence as the lube oil is not used in the operation of the unloader

Which of the illustrated motors has an open, drip-proof (ODP) motor enclosure? Illustration EL-0001

1. A
2. B
3. C ✓
4. D

How is the difference between the synchronous speed of a three-phase induction motor and its operating speed correctly expressed?

1. deviation
2. a decimal fraction of full load speed
3. slip ✓
4. a percent of full load speed

What type of AC motor would use a rheostat in the rotor circuit to vary the speed of the motor?

1. wound-rotor induction motor ✓
2. synchronous motor
3. regenerative braking motor
4. squirrel-cage induction motor

Which of the following voltage testers would be associated with high quality, be safe to use, and minimize the electric shock hazard?

1. a voltage tester with a high input impedance and a voltage rating higher than any expected measured voltages ✓
2. a voltage tester with a high input impedance and a lower voltage rating than any expected measured voltages
3. a voltage tester with a low input impedance and a higher voltage rating than any expected measured voltages
4. a voltage tester with a low input impedance and a lower voltage rating than any expected measured voltages

Fuel oil solenoid valves at the burner fronts should be of the manual reset type to __________.

1. permit the operator to secure each burner during a blackout
2. prevent the furnace from filling with oil after restoration of power ✓
3. prevent the furnace from filling with oil during a power failure
4. permit the operator to secure each burner after a blackout

Insufficient combustion air supply will cause an atomizer flame to appear as a __________.

1. dull red flame with black streaks ✓
2. ragged flame
3. pointed flame
4. light yellow flame with white streaks

Auxiliary steam at full operating pressure is supplied from the boiler directly to the __________.

1. turbogenerators
2. main air ejectors
3. distilling plants
4. sootblowers ✓

Which of the petroleum products listed has a flash point below 150°F?

1. Road oils
2. Light fuel oils ✓
3. Lubricating oils
4. Asphalt

In order for a live-line tester to be used to test and prove dead a high voltage circuit, what must be done to verify the ability of the tester to detect a voltage?

1. The live-line tester need not be checked prior to testing the circuit to be worked upon as long as it has not been declared inoperative.
2. The live-line tester should be checked by connecting to a known high voltage source only before testing the circuit to be worked upon.
3. The live-line tester should be checked by connecting to a known high voltage source before and after the circuit to be worked upon is tested. ✓
4. The live-line tester should be checked by connecting to a known high voltage source only after testing the circuit to be worked upon.

Which of the following actions should be taken FIRST when water is found in the fuel oil settling tank?

1. Determine the extent of water contamination by reading the pneumercators.
2. Shift to alternate or standby fuel oil service pump.
3. Sound the settling tank with water indicating paste.
4. Shift pump suction to an alternate settling tank. ✓

The most practical method of determining the condition of a shaft bearing while the shaft is in operation is to __________.

1. check the lube oil viscosity
2. visually inspect the bearing
3. perform a carbon blot test on an oil sample from the bearing
4. check the lube oil temperature ✓

One method of constructing large marine diesel engines and reducing the total engine frame weight is through __________.

1. casting interlocking components
2. welding plates to form sections for assembly ✓
3. forging integral components
4. case hardening integral components

In a modern two stroke, slow speed, internal combustion diesel engine, what is the part of the engine that houses the crankshaft?

1. bedplate ✓
2. sump
3. cylinder block
4. frame

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

1. The engine should be running at idle RPM with no load (propulsion clutch disengaged).
2. The engine should be running at idle RPM with minimal load (propulsion clutch engaged).
3. The engine should be running at rated RPM with full load (propulsion clutch engaged). ✓
4. The engine should be running at rated RPM with no load (propulsion clutch disengaged).

Hydraulic starters are installed on many lifeboat diesel engines instead of comparable air start systems, because __________.

1. hydraulic starters are the least expensive of all starting systems
2. the system does not require high-pressure piping
3. hydraulic systems turn diesel engines at higher rates of speed than air starters
4. the system can be manually recharged ✓

As shown in the illustration of the fuel injection pump, the component labeled "N" would be identified as the __________. Illustration MO-0061

1. control rack
2. sleeve
3. plunger
4. barrel ✓

What is the purpose of the delivery check valve used in a diesel fuel injection jerk pump?

1. To assist in a quick cutoff of fuel injection ✓
2. To allow oil backflow from the injector to the helix
3. To meter the quantity of fuel delivered
4. To reduce fuel oil pressure between injection strokes

The expansion tank for a diesel engine closed cooling system is designed to maintain a constant head on the system and __________.

1. Provide an aircushion
2. Reduce water temperature
3. Reduce water turbulence
4. Allow for an increase in water volume as the engine warms up ✓

When installing the bearing cap on the device shown in the illustration, which of the precautions listed must be observed? Illustration MO-0121

1. Prior to installing the cap, position the thrust shoes in their proper locations.
2. Once the bearing cap is properly torqued, measure the end gap dimensions to ascertain even tightening of the cap. ✓
3. If the device is covered with abrasive material or contaminates, the unit may be reassembled, provided an abnormal method of reassembly is followed.
4. After applying anti-seize to the external threads, torque one side at a time to the appropriate values using a quality torque wrench.

The main engines on your vessel are fitted with speed control governors based on the operating principle shown in the illustration. What statement is true concerning the illustrated pressure-compensated governor? Illustration MO-0159

1. With the speeder spring compression force and the flyweight centrifugal force in equilibrium, the flyweights are pivoted outward and the pilot valve plunger will be in the lowered position aligning the control port to the drain port.
2. With the speeder spring compression force and the flyweight centrifugal force in equilibrium, the flyweights are pivoted inward and the pilot valve plunger will be in the raised position aligning the control port to the pressure port.
3. With the speeder spring compression force and the flyweight centrifugal force in equilibrium, the flyweights are pivoted to vertical and the pilot valve plunger will be in the centered position blocking off the control port. ✓
4. With the speeder spring compression force and the flyweight centrifugal force in equilibrium, the flyweights are pivoted to vertical and the pilot valve plunger can be positioned in any position.

The primary function of a flame safeguard system, as used on an automatically fired auxiliary boiler, is to prevent what condition?

1. Accidental dry firing and overpressure
2. Uncontrolled fires in the furnace
3. Explosions in the boiler furnace ✓
4. Overheating of the pressure parts

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

1. Reduce the load and speed on the engine and continue to monitor the oil pressure.
2. Monitor closely oil pressures, temperatures, and levels while continuing to run the engine.
3. Immediately add make-up oil or service lube oil coolers, strainers, and filters, as appropriate.
4. Immediately shut down the engine, then investigate the cause for the low-pressure alarm. ✓

After a main diesel engine on your vessel has experienced a safety shutdown due to excessive crank-case pressure, why is it important to wait 2 hours before opening the crankcase to investigate the cause of the trip?

1. Opening the crankcase before 2 hours has elapsed may result in a crankcase explosion. ✓
2. Opening the crankcase before 2 hours has elapsed may result in the engine spontaneously restarting.
3. Opening the crankcase before 2 hours has elapsed may result in crankshaft rotation.
4. Opening the crankcase before 2 hours has elapsed may result in excessively rapid cooling.

Steam assist fuel atomizers are converted to straight mechanical atomizers in order to __________.

1. Raise steam on the idle boiler
2. Cold start a boiler with diesel oil ✓
3. Provide the best fuel economy
4. Meet minimum boiler steam demands

The advantage of installing waterwall tubes in a boiler furnace is to __________.

1. permit higher combustion rates ✓
2. increase heat transfer to the mud drum
3. increase the flow of gases through the furnace
4. decrease the flow of gases through the furnace

Which color burner flame would indicate too much excess air?

1. Yellowish orange
2. Bright red
3. Incandescent white ✓
4. Orange red

A single element boiler feedwater regulating system used aboard ship utilizes __________.

1. proportional plus reset action
2. proportional plus reset plus rate action
3. two-position differential gap action
4. proportional action ✓

In an impulse turbine, the fixed blades function to __________.

1. prevent steam turbulence
2. decrease steam velocity
3. equalize pressure differences
4. change the direction of steam flow ✓

Labyrinth seals are used on rotating steam turbine shafts to reduce external leakage. How is this accomplished?

1. Successive temperature drops through the seal stages
2. Successive pressure drops through the seal stages ✓
3. Increased turbulence through successively larger labyrinth clearances
4. Pressure increases through successive seal stages

Before placing the jacking gear in operation on a main turbine unit, you must always ensure that __________.

1. the main lube oil system is operating ✓
2. the condensate system is operating
3. the gland seal steam system is operating
4. the main saltwater circulating pump is operating

Labyrinth seals used to reduce leakage around a turbine shaft are constructed of __________.

1. spring bound carbon segments
2. braided asbestos covered core segments
3. machined metallic packing strips or fins ✓
4. staged rubber composition seal stripping

To test an automatic low lube oil pressure trip on an idling turbogenerator and at the same time prevent the chance of bearing damage, you should __________.

1. secure the steam supply valve to the throttle valve and observe the oil pressure as the throttle trips during the slowdown and ensure a supply of oil with the hand or standby pump when the pressure drops to 2-3 psi ✓
2. actuate the overspeed trip, making a note at what pressure the oil is dumped from under the operating piston
3. ensure the standby lube oil pump, if so equipped, is properly lined up and set in the "auto" mode, or the hand pump is being operated and then actuate the emergency trip
4. close the generator steam throttle valve and then ensure a supply of oil through the hand or standby pump when the pressure drops to 5-6 psi

Chamfers, located at the parting edges of horizontal split sleeve type bearings, are used to facilitate oil storage and distribution. They are machined __________.

1. radially the full length of the bearing
2. axially, approaching but not extending to the end of the bearing ✓
3. axially the full length of the bearing
4. radially, to within 45 degrees of the normal bearing surface

As found in a reduction gear drive system, thrust bearings serve to __________.

1. transmit the force produced by the propeller to the structure of the ship ✓
2. increase the shaft speed
3. limit the radial movement of the shaft
4. hold the main engine in place

Which of the listed sequence of events occurs when an automatic auxiliary boiler is pre-purged?

1. The damper on the inlet side of the furnace is moved to the open position for a given number of seconds and then moved to the closed position.
2. The damper on the inlet side of the furnace is moved to the open position for a given number of seconds and then moved to the low fire position. ✓
3. The damper is moved to the closed position for a given number of seconds and then moved to the low fire position.
4. The damper in the uptakes is moved to the wide-open position for a given number of seconds and then moved to the low firing rate position.

Compared to other types of engines, what is the biggest advantage of a gas turbine engine?

1. Simplicity of installation
2. Simplicity of the control circuits
3. Low power-to-weight ratio
4. Highest power-to-weight ratio ✓

The acronym GG represents which of the following?

1. Vibration-gas generator
2. Temperature-gas generator
3. Speed-gas generator
4. Gas generator ✓

The acronym FOD stands for which of the following?

1. Flow offset design
2. Foreign object damage ✓
3. Fuel oil discharge
4. Fuel override demand

Under standard atmospheric conditions, 208.7 PSIG converts to approximately what in absolute pressure?

1. 104.7 PSIA
2. 223.4 PSIA ✓
3. 214.7 PSIA
4. 194.0 PSIA

Which of the following terms refers to thermal energy in transition?

1. Power
2. Horsepower
3. Heat ✓
4. Foot-Pound

Variable stator vanes give an axial gas turbine compressor which of the following capabilities?

1. Ability to maintain constant turbine primary air flow across all speeds.
2. Ability to maximize turbine surge capacity across all speeds.
3. Ability to maximize turbine efficiency across all speeds. ✓
4. Ability to maintain constant turbine compression ratio across all speeds.

Which of the following statements is true about the "lockout control" on a synchronous self-shifting (SSS) clutch?

1. It is an automatically operated control.
2. The mechanism is incorporated into the input assembly of the clutch.
3. Permits operation of the GTE without the rotation of the main reduction gear. ✓
4. None of the above.

Rotation of the controllable-pitch propeller (CPP) blades is achieved through axial movement of what component in the hub body assembly?

1. Crosshead ✓
2. Sliding block
3. Crank pin ring
4. Servomotor piston

Compressor surge is caused by which of the following factors?

1. Maximum fuel pressure
2. Increased demand for secondary air
3. Low ambient air temperature
4. Interrupted air flow ✓

When a compressor is in a stall condition, what will happen to the combustor and turbine temperatures?

1. Rapidly increase ✓
2. Slowly increase
3. Slowly decrease
4. Rapidly decrease

What is meant by the term independent bilge suction?

1. The means by which the machinery space bilge is pumped out by a pump not normally used as a bilge pump but using either bilge manifolds or automatic bilge suction valves.
2. The means by which a cargo-hold bilge is pumped out by a pump normally used as a bilge pump but independent of any bilge manifolds or automatic bilge suction valves.
3. The means by which a cargo-hold bilge is pumped out by a pump not normally used as a bilge pump but using either bilge manifolds or automatic bilge suction valves.
4. The means by which the machinery space bilge is pumped out by a pump normally used as a bilge pump but independent of any bilge manifolds or automatic bilge suction valves. ✓

With regard to a ballast system associated with a dry cargo ship, what is the primary purpose of the fore peak and aft peak tanks?

1. Correcting a condition of hogging or sagging of the vessel
2. Adjusting the overall draft of the vessel
3. Correcting a list condition on the vessel
4. Adjusting the trim of the vessel ✓

Which of the following statements represents the proper procedural sequence for adjusting the metering rate of an in-line lubricator as used in a ship's service air system hose station? Assume that the pressure regulator has been properly set.

1. Establish normal air flow. Determine drip rate. Further open needle valve to increase drip rate or further close needle valve to decrease drip rate, as appropriate. ✓
2. Establish normal air flow. Determine drip rate. Further open needle valve to decrease drip rate or further close needle valve to increase drip rate, as appropriate.
3. Temporarily shut-off air flow. Determine drip rate. Further open needle valve to increase drip rate or further close needle valve to decrease drip rate, as appropriate. Re-establish normal air flow.
4. Temporarily shut-off air flow. Determine drip rate. Further open needle valve to decrease drip rate or further close needle valve to increase drip rate, as appropriate. Re-establish normal air flow.

If a belt-driven reciprocating air compressor is operating at a lower than design displacement capacity (in cubic feet per minute), which of the following would be a cause?

1. Excessively tensioned drive belts.
2. Insufficiently tensioned drive belts. ✓
3. Misalignment between the compressor and its driver.
4. Improperly lubricated bearings.

With regard to the number of passes through the tubes of shell-and-tube heat exchangers, what statement is true?

1. In two-pass and four-pass heat exchangers, the inlet and outlet tube-side fluid connections are at the same end. ✓
2. In single-pass and two-pass heat exchangers, the inlet and outlet tube-side fluid connections are at the same end.
3. In single-pass and two-pass heat exchangers, the inlet and outlet tube-side fluid connections are at opposite ends.
4. In two-pass and four-pass heat exchangers, the inlet and outlet tube-side fluid connections are at opposite ends.

A flare-type tubing connector is used in the hydraulic hatch cover system and has developed a slight leak. To stop the leak, you should __________.

1. Stop the system and use only one wrench to tighten the flare nut
2. Keep the system in operation and tighten the flare nut
3. Shut down the power unit and use two wrenches to avoid damaging the tubing when tightening ✓
4. Replace both the tubing sections and the fitting

Which characteristic or condition will have the greatest effect on increasing a hydraulic oil's viscosity?

1. Cloud point
2. Pour point
3. Vacuum
4. Pressure ✓

With respect to lubricating oils, what statement is true concerning viscosity and viscosity index?

1. Viscosity is a measure of an oil's internal resistance to flow and viscosity index is a measure of an oil's ability to resist change in viscosity as the temperature changes. ✓
2. Viscosity is a measure of an oil's resistance to emulsification and viscosity index is a measure of an oil's ability to resist change in viscosity as the temperature changes.
3. Viscosity is a measure of an oil's ability to resist oxidation and viscosity index is a measure of an oil's ability to resist change in viscosity as the temperature changes.
4. Viscosity is a measure of an oil's lubricity and viscosity index is a measure of an oil's ability to resist change in lubricity as the pressure changes.

What effect does preheating, concurrent heating, or post heating have on welding a joint?

1. Increasing the temperature gradient in the weld area and intensifying internal stresses.
2. Increasing the temperature gradient in the weld area and relieving internal stresses.
3. Decreasing the temperature gradient in the weld area and relieving internal stresses. ✓
4. Decreasing the temperature gradient in the weld area and intensifying internal stresses.

A 'centerline' depicted in a drawing or blueprint is represented by which of the figures shown in the illustration? Illustration GS-0031

1. A
2. E ✓
3. C
4. D

Air leakage between the shaft and stuffing box packing in a centrifugal pump is prevented by __________.

1. lantern rings between the packing rings
2. the stuffing box gland
3. a compressed packing gland
4. a liquid seal ✓

On a ship with a continuously manned engine room, with a three-person watch rotation, what is the watch and rest period rotation?

1. 4 hours on watch followed by 8 hours rest ✓
2. 6 hours on watch followed by 6 hours rest
3. 8 hours on watch followed by 4 hours rest
4. 8 hours on watch followed by 8 hours rest

What is the physical state and pressure condition of refrigerant as it leaves a receiver in a typical refrigeration system?

1. high-pressure vapor
2. high-pressure liquid ✓
3. low-pressure liquid
4. low-pressure vapor

In a refrigeration system, the bulb for the thermal expansion valve is always located where?

1. in the middle of the evaporator coils
2. at the evaporator coil inlet
3. at the evaporator coil outlet ✓
4. at the beginning of the bottom row of the evaporator coils

The amount of HCFC-123 in a storage cylinder is measured by what means?

1. saturation temperature
2. weight ✓
3. saturation pressure
4. volume