Motor Engineering – MEO CLASS 4 MMD PAPER

SECTION 3

1. The color of the exhaust from a diesel engine should be
   A. clear
   B. hazy light brown
   C. hazy light blue
   D. hazy light grey

ANS.: A

2) In jerk type large fuel injection pumps, pulsations are absorbed by:

A. The fuel pump resilient foundation
B. The high pressure pipes
C. The shock absorbers mounted on fuel pumps
D. The shock absorbers mounted on high pressure pipes

ANS.: C

3) Which of the following can be a possible outcome of salt water contamination in fuel?

A. Cavitation and erosion of fuel injection components.
B. High temperature corrosion in exhaust valves and turbochargers
C. Unstable combustion
D. All of the above

ANS.: D

4) The water in a steaming auxiliary boiler should be tested daily for

A. dissolved oxygen
B. chlorides
C. sludge
D. dissolved nitrogen

ANS.: B

5) What fittings do you normally find in a main engine turbocharger prior to compressor inlet in the air flow path ?

A. Pre-filter and diffuser
B. Pre-filter , silencer and diffuser
C. Pre-filter , silencer and inducer
D. Pre-filter , silencer vibration damper

ANS.: C

6) Unit of kinematic viscosity

1. centipoises
2. centistokes
3. CCAI
4. none of above

ANS.: B

7) Exhaust valve seat material

1. stainless steel,
2. invar,
3. nimonic
4. inconnel

ANS.: D

8) Drop in compression pressure with high scavange box temp in a cylinder

1. late injection
2. early injection,
3. worn piston ring
4. leaky exhaust valve

ANS.: C

9) Which of the following statements is true?

A. The higher the viscosity index of a lubricant, the higher is the change of viscosity with temperature.
B. The higher the viscosity index of a lubricant, the lower is the change of viscosity with temperature.
C. Viscosity index is not a measure of a fluid’s change in viscosity with temperature.
D. None of the above

ANS.: B

10) In case of cross scavenged engines :

A. The exhaust ports are located above the scavenge ports and they open everytime the piston reaches near TDC and near BDC
B. The exhaust ports are located below the scavenge ports and they open everytime the piston reaches near TDC and near BDC
C. The exhaust ports are located above the scavenge ports and they open everytime the piston reaches near BDC
D. The exhaust ports are located below the scavenge ports and they open everytime the piston reaches near BDC

ANS.: C

11) While overhauling a piston rod stuffing box, if the butt clearance of scraper rings is found below or near the minimum, the correct remedial measure would be ______

A. To file the ends of the rings and increase the clearance
B. To renew the ring set or fit new lamellae
C. To swap the lower rings with the upper rings
D. To renew a segment or two of ring set to obtain the desired clearance

ANS.: A

12) In a electro- hydraulic steering gear, the movement of actuator is created by ___________

A. Starting the motors on both power units
B. Operating the isolating valves
C. Starting at least one power unit and actuating the direction valves
D. Starting both power units and actuating the direction valves

ANS.: C

SECTION 4

1)  A large change in ambient temperature, or using an oil of a viscosity different than the one recommended by the manufacturer in a mechanical hydraulic governor, will result in the need to adjust the

1. pilot valve opening
2. compensating needle valve
3. compensating spring tension
4. accumulator spring tension

ANS.: B

2)  When the prime movers of two paralleled generators, equipped with mechanical-hydraulic governors, are operating within their designed range, the unit with the least amount of speed drop will –

1. pick up more of any increase in load
2. pick up less of any increase in load
3. share an equal amount of any increase in load
4. drop an equal amount of any decrease in load

ANS.: A

3)  Clearance volume scavenging in a turbocharged , four-stroke/cycle diesel engine is accomplished

1. during the valve overlap period
2. with only the exhaust valve open
3. at a pressure below atmospheric
4. without cooling the cylinders or pistons

ANS.: A

4)  Trunk-type diesel engine pistons are most effectively cooled by heat uscg94

1. conducted through the engine block
2. conducted to water cooled cylinder walls
3. conducted through the piston crown
4. losses to escaping exhaust gasses

ANS.: B

5)   Fuel oil is injected into the cylinder of a four-stroke/cycle diesel engine during the

1. intake stroke
2. exhaust stroke
3. power stroke
4. compression stroke

ANS.: D

6)   The total starting air capacity required for reversible main engines is to be sufficient for a least

1. six consecutive starts
2. eight consecutive starts
3. ten consecutive starts
4. twelve consecutive starts

ANS.: D

7)  The light and medium fuels utilized in internal combustion engines provide a source ofuscg120

1. lubrication for pistons and rings
2. food for microbiological organisms
3. gases most detrimental to the ozone layer of the atmosphere
4. all of the above

ANS.: B

8)  Which bearing half will receive the greatest load in a two-stroke/cycle diesel engine?

1. Lower half of the connecting rod bearing at the crankshaft end of the rod
2. Upper half of the main bearing
3. Lower half of the piston pin bearing in the connecting rod
4. All bearing halves share an equal load

ANS.: C

9)  A naturally aspirated diesel engine at full throttle will have an intake manifold pressure  uscg136

1. slightly less than atmospheric pressure
2. approximately equal to exhaust manifold pressure at all times
3. That is widely fluctuating
4. constantly decreasing as engine load increases

ANS.: A

10)  The output pressure of a diesel engine lube oil pump is regulated by a/an

1. relief valve
2. metering valve
3. variable speed pump drive
4. orifice in the lube oil header

ANS.: A

11)   An increase in the air inlet manifold pressure of a diesel engine will result in a/an uscg 146

1. decrease in maximum cylinder pressure
2. increase in ignition lag
3. decrease in fuel consumption per horsepower-hour
4. decrease in exhaust manifold pressure

ANS.: C

12)   Maximum lube oil system pressure is normally controlled by

1. the capacity of the lube oil pump
2. the speed of the lube oil pump
3. the outlet pressure of the lube oil pump
4. a relief valve

ANS.: D

 13)   Which of the following statements is true concerning an oil cooler?

1. The oil temperature is less than the cooling water temperature
2. The oil pressure is less than the cooling water pressure
3. The oil pressure is greater than the cooling water pressure
4. The magnets are installed to remove metal particles

 ANS.: C

14)  Concerning diesel propelled vessels, the astern power is to provide for continues operation astern

1. equal to that available for ahead operation
2. at 70 percent of the ahead rpm at rated speed
3. while underway and under all normal conditions
4. at 70 percent of the ahead rpm of average continuous sea speed

ANS.: B

15) Maintaining the lowest possible scavenging air temperature at all times is not recommended due to the possibility of the

1. air charge density becoming too high
2. piston crown surfaces becoming too cold
3. formation of excessive quantities of condensate
4. compression pressure being greatly reduced

ANS.: C

 16)  The nuts of main bearings, connecting rod bolts and all other moving parts are to be secured by

1. hardened steel nut locks
2. cotter pins made of spring steel
3. split pins or other effective means
4. hydraulic nuts as commonly found on large low speed engines

ANS.: C