1. While diesel engine is operating ,one of the important pressure to check is ______
- A. steam pressure
- B. exhaust gas
- C. lubricating oil
- D. sarting air
Answer: C — lubricating oil
While checking various parameters is important, the lubricating oil pressure is a critical indicator of proper lubrication, essential for preventing engine damage. Low oil pressure signals a potential problem with the lubrication system and requires immediate attention.
2. One of the function of lubricating oil in a diesel engine is to reduce
- A. weight of the engine
- B. wexhaust gases
- C. friction between moving parts
- D. exhaust temperatures
Answer: C — friction between moving parts
The primary function of lubricating oil in a diesel engine is to reduce friction between moving parts, thereby minimizing wear and heat generation. It also provides cooling and sealing, but friction reduction is its most crucial role.
3. Function of crankcase lubricating oil in a diesel engine is to ____
- A. prevent corrosion
- B. supply power
- C. improve combustion
- D. turn crankshaft
Answer: A — prevent corrosion
Lubricating oil within the crankcase serves multiple purposes, including lubricating the crankshaft and connecting rod bearings, cooling these components, and preventing rust and corrosion on internal surfaces. It does not directly improve combustion or supply power.
4. The lower most ring on a diesel engine piston is called
- A. oil scraper ring
- B. compression ring
- C. pressure ring
- D. split ring
Answer: A — oil scraper ring
The bottom-most ring on a piston, typically featuring a tapered or spring-loaded design, is the oil scraper ring. Its function is to scrape excess lubricating oil from the cylinder walls during the piston's downstroke, preventing it from entering the combustion chamber.
5. For good combustion, the color of the exhaust from diesel engine should be
- A. bluish white
- B. light brown
- C. colourless
- D. light grey
Answer: C — colourless
For efficient combustion in a diesel engine, the exhaust gases should be colourless, indicating complete burning of the fuel. Any discolouration, such as black, blue, or white smoke, signifies incomplete combustion or other issues needing attention.
6. Ships propeller is fitted to
- A. intermediate shaft
- B. stern tube
- C. crankshaft
- D. tail shaft
Answer: D — tail shaft
The ship's propeller, which provides propulsion by converting engine power into thrust, is directly attached to the end of the tail shaft. This shaft extends from the gearbox or engine through the stern tube to the propeller.
7. The type of engine normally used for generators on a ship is ____________
- A. 4 stroke
- B. 6 stroke
- C. 2 stroke
- D. medium stroke
Answer: A — 4 stroke
Four-stroke engines are generally preferred for ship generators due to their better fuel efficiency, smoother operation, and lower emissions compared to two-stroke engines, which are typically used for main propulsion in larger vessels.
8. When starting engine on diesel oil, before injection the oil is
- A. heated to same temp s heavy oil
- B. passed through the purifier
- C. heated if necessary in cold climate
- D. mixed with steam
Answer: C — heated if necessary in cold climate
Diesel oil, used for generators and smaller engines, has a lower ignition point than heavy fuel oil and typically does not require significant heating for injection. It may require warming in very cold climates, but not to the extent of HFO, nor is it typically mixed with steam.
9. A cam shaft on diesel engine operates
- A. starting valves
- B. fuel valves
- C. flywheel
- D. fuel injection pump
Answer: D — fuel injection pump
The camshaft, driven by the engine's timing gears or chain, has lobes that push open the valves. It directly operates the fuel injection pumps in many diesel engine designs, ensuring precise fuel delivery timing.
10. Thrust block for main engine is fitted at the
- A. tail shaft
- B. aft side of engine
- C. forward side of engine
- D. end of the cam shaft
Answer: B — aft side of engine
The thrust block is a specialized bearing designed to absorb the significant axial thrust generated by the propeller and transmitted through the propeller shaft. It is fitted at the aft end of the engine, in line with the shafting, to transfer this force to the ship's structure.
11. The purpose of Injector valve on a generator engine is for _____
- A. Fresh air intake
- B. Safety
- C. Compress air
- D. Fuel inlet
Answer: D — Fuel inlet
The injector valve, also known as a fuel injector, is responsible for injecting a precisely metered amount of fuel into the engine cylinder at the correct time and pressure for combustion. Its primary role is fuel delivery, not safety or air intake.
12. Exhaust valve in a Diesel engine ______
- A. Rotates in place
- B. Stays in place
- C. Moves up and down
- D. Opens and closes
Answer: D — Opens and closes
The exhaust valve in a diesel engine is a critical component that opens to allow burned exhaust gases to exit the cylinder and closes to seal the combustion chamber during the compression and power strokes. Thus, it must open and close cyclically.
13. What specific safety precaution must be observed when managing human factors, communication, and risk assessment for Marine Engineering Knowledge on board?
- A. Disabling automated safety alarms to save time
- B. Delegating tasks exclusively to untrained crew members
- C. Proceeding without informing the officer on watch
- D. Conducting a thorough risk assessment and briefing all involved personnel prior to starting work
Answer: D — Conducting a thorough risk assessment and briefing all involved personnel prior to starting work
Risk assessments and pre-job briefings ensure all team members understand hazards during Marine Engineering Knowledge operations.
14. Piston in a Diesel engine _______
- A. Oscillates
- B. Moves up and down
- C. Rotates in place
- D. Stays in place
Answer: B — Moves up and down
In a diesel engine's operational cycle, the piston is designed to reciprocate, meaning it moves linearly up and down within the cylinder. This reciprocating motion is fundamental to converting the energy from fuel combustion into rotational mechanical work via the crankshaft.
15. The purpose of Exhaust Gas in a Diesel engine is to ___
- A. Turns turbo charger
- B. Reduces friction
- C. Gives power
- D. Increases air supply
Answer: A — Turns turbo charger
The primary purpose of the exhaust gases, which are at high temperature and pressure, is to drive the turbine wheel of the turbocharger. This rotation then powers the compressor, which forces more air into the cylinders, thereby increasing engine power and efficiency.
16. What is to be checked on a running Main engine , during watch.
- A. Oil coming out of water side
- B. Steering angle
- C. Exhaust temperature
- D. Discharge pressure of liquid
Answer: C — Exhaust temperature
During a watch, monitoring the exhaust temperature of the main engine is crucial. Abnormal fluctuations can indicate potential issues like cylinder imbalance, cooling problems, or combustion irregularities, allowing for early intervention.
17. Air starting valve in a Diesel engine _____
- A. Moves from side to side
- B. Oscillates
- C. Opens only at engine starting
- D. Moves up and down
Answer: C — Opens only at engine starting
The air starting valve in a diesel engine is designed to operate intermittently. It opens only during the starting sequence to admit compressed air into the cylinders, initiating rotation; it remains closed during normal operation.
18. The purpose of Indicator valve on a generator engine is for _________
- A. Compressed air
- B. Blowing through
- C. Fuel inlet
- D. Fresh air intake
Answer: B — Blowing through
The indicator valve on a diesel engine serves as a port to connect a pressure indicator or to release compressed air during the 'blowing through' phase before starting. This allows for clearing residual gases or checking cylinder compression.
19. Which of these is NOT a moving part of a diesel engine:
- A. Piston
- B. Crankcase
- C. Connecting rod
- D. Crankshaft
Answer: B — Crankcase
The crankcase forms the main body of the engine housing but is typically stationary. The connecting rod, piston, and crankshaft are all essential moving components that translate combustion forces into rotational motion.
20. Cylinder Head in a Diesel engine ____
- A. Stays in place
- B. Rotates in place
- C. Moves up and down
- D. Oscillates
Answer: A — Stays in place
The cylinder head is a fixed component that seals the top of the engine cylinder. It houses the valves and injectors and remains stationary during the engine's operation.
21. The purpose of Inlet valve on a generator engine is for ________
- A. Compress air
- B. Fresh air intake
- C. Safety
- D. Fuel inlet
Answer: B — Fresh air intake
The purpose of the inlet valve on a generator engine is to allow the intake of the fresh air-fuel mixture into the cylinder for combustion. This process is critical for the engine's power generation cycle.
22. The purpose of Exhaust valve on a generator engine is for _________
- A. Fuel inlet
- B. Combustion Gases
- C. Stop fuel
- D. Fresh air intake
Answer: B — Combustion Gases
The exhaust valve on a generator engine opens to allow the expulsion of burnt combustion gases from the cylinder. This clears the cylinder, preparing it for the next intake stroke.
23. Before starting a generator engine, LO hand pump should be operated to
- A. Turn the engine
- B. Warm up the engine
- C. Supply lub oil to moving parts
- D. Check the level of the tank
Answer: C — Supply lub oil to moving parts
Operating the LO hand pump before starting a generator engine ensures that lubrication oil is distributed to critical moving parts. This pre-lubrication is vital to minimize wear and prevent damage during the initial start-up phase.
24. Connecting rod in a Diesel engine ___________.
- A. Moves up and down
- B. Oscillates
- C. Rotates in place
- D. Stays in place
Answer: B — Oscillates
The connecting rod in a diesel engine undergoes an oscillating motion. It links the reciprocating piston to the rotating crankshaft, converting the linear movement into rotational movement.
25. The purpose of Fuel Oil in a Diesel engine is to _____
- A. Causes explosion
- B. Reduces friction
- C. Turns turbo charger
- D. Gives power
Answer: D — Gives power
The primary function of fuel oil in a diesel engine is to provide the energy for combustion. When ignited under pressure, it releases chemical energy, which is converted into mechanical power to drive the engine.
26. The purpose of Lubricating Oil in a Diesel engine is to _______
- A. Gives power
- B. Turns turbo charger
- C. Increases air supply
- D. Reduces friction
Answer: D — Reduces friction
Lubricating oil plays a crucial role in a diesel engine by reducing friction between moving parts. This minimizes wear, dissipates heat, and prevents seizing, thereby ensuring efficient and prolonged engine operation.
27. Crankshaft in a Diesel engine _______
- A. Rotates in place
- B. Moves up and down
- C. Stays in place
- D. Oscillates
Answer: A — Rotates in place
The crankshaft in a diesel engine is designed to rotate continuously. It converts the reciprocating motion of the pistons, transmitted through the connecting rods, into the rotational force needed to drive the propeller shaft.
28. The purpose of "COMPRESSED AIR" in a diesel engine is to_________
- A. Starts Engine
- B. Controls fuel Supply
- C. Gives Power
- D. Turns turbo Charger
Answer: A — Starts Engine
Compressed air is used in diesel engines primarily for starting the engine. It is injected into the cylinders at high pressure to initiate the crankshaft's rotation, allowing the combustion cycle to begin.
29. Generator engine on board ships is started using
- A. Compressed air
- B. Turbo generator
- C. Hydraulic Oil Motors / Pressure
- D. Air compressor
Answer: A — Compressed air
Generator engines on ships are typically started using a compressed air system. A dedicated starting air receiver stores air under pressure, which is then admitted to the cylinders to turn the engine over.
30. Function of crankcase lubricating oil in a diesel engine is to reduce friction between moving parts, cooling the parts and to _______________
- A. Improve combustion
- B. Prevent corrosion
- C. Supply power
- D. Turn the crankshaft
Answer: B — Prevent corrosion
Besides reducing friction and cooling, lubricating oil in the crankcase also serves to prevent corrosion on internal engine components. It forms a protective film that inhibits rust and oxidation, especially during periods of inactivity.
