Anna University-Automotive Engines-Question bank



 AUTOMOTIVE  ENGINES

QUESTIONS FROM UNIVERSITY EXAM

Semester: III                                                                          Max. Marks: 100

PART – A                                                                              (10 x 2 = 20 marks)


  1. What is the use of air standard cycle?
  2. Draw the Otto cycle on P-V diagram
  3. what are the firing order used in 4 and 6 cylinder engines
  4. what is stiochiometric air fuel ratio
  5. what are the three basic types of carburetors
  6. what are the different methods of engine cooling
  7. what is blow by
  8. what is flame front
  9. what are the various types of combustion chambers used in SI engines
  10. what is scvangening efficiency
  11. what is short circuiting
  12. what is carnot cycle  and its importance
  13. What are different air fuel mixtures on which an engine can operate
  14. Write down the firing order for four and six cylinder engines
  15. what is indicator diagram
  16. what is the necessity of firing order in a multicylinder engines
  17. what are the mixture limits for inflammability
  18. what is the difference between a constant choke carburetor and a constant vacuum carburetor
  19. what is a thermostat
  20. what is the need for providing crankcase ventilation
  21. what are the variable s that affect the knock of SI engines
  22. How is the location of the spark plug can influence knocking tendency
  23. why scavenging is important in two stroke engines compared to four stroke engines
  24. Define trapping efficiency
  25. List the different types of ignition system used in vehicles 
  26. What is the use of condenser in ignition system
  27. What are the main functions of air injection pump?
  28. What is meant by crank case ventilation?
  29. Write the reason for cooling an engine
  30. what is the advantage of air cooling system
  31. what is meant by abnormal combustion
  32. What is delay period and what are the factors that affect the delay period?
  33. Define enthalpy
  34. Write down the components of ignition system used in automobiles
  35. Write down the possible faults in conventional ignition system


  1. Draw the diagram for an ignition coil and name the components
  2. Write any four advantage of  4 stroke petrol engine over 2 stroke petrol engine
  3. write the air standard efficiency of an Otto cycle
  4.  write ant four factor that affects the process of combustion
  5. what are the various requirement of good carburetor
  6. what is the main function of an spark plug
  7. write different methods of SI lubricating system
  8. write the reason for cooling an engine
  9. what is meant by abnormal combustion
  10. What is a homogeneous and heterogeneous mixture?
  11. what is opposed piston engine
  12. Define dwell angle and mention its importance
  13. Briefly explain about two types of spark plug used in automobiles
  14. List the advantage of Electronic ignition system with conventional type
  15. Write down the firing order for four and six cylinder engines
  16. List the different types of ignition system used in vehicles 
  17. What is the use of condenser in ignition system
  18. Write down the components of ignition system used in automobiles
  19. Write down the possible faults in conventional ignition system
                                            
PART – B                                                                                    (16 x 2 = 32 marks)

  1. Compare four stroke and two stroke cycle engines and bring out their relative merits and demerits
  2. Describe with suitables sketches the idling system and accelerating pump of a modern carburetor
  3. sketch a mechanical fuel pump and describe its working
  4. Explain with a neat sketch the forced circulation cooling system
  5. Discuss the different properties of lubricants
  6. Discuss the design criteria for a S.I engine combustion chamber
  7. Explain with neat sketches the two different types of two stroke engines
  8. Explain the various scavenging pumps used in a two stroke engines
  9. Discuss the two stroke engine construction and operation with neat sketches
  10. with a neat sketch explain the working principles of a simple carburetor
  11. Explain briefly the electronic fuel injection system used in some modern cars
  12. Explain with neat sketches the thermosypon cooling system and pressure cooling system
  13. Discuss the various types of combustion chambers used in SI engines
  14. Explain with a graph the three possible theoretical scvangening processes
  15. Explain with neat sketch the cross flow scvangening and uniflow scvangening 
  16. Briefly explain the principle of four stroke petrol engine with a simple sketch
  17. Draw the ideal and actual indicator diagram for a four stroke petrol engine and explain why they differ each other.
  18. Draw the sketch of a downdraught carburetor. How do the idle and low speed circuits work in this carburetor

  1. Briefly explain the working principle of line fuel injection pump
  2. Explain the dry sump lubricating system with neat sketch
  3. What is an air cooling system and in which type of engine it is normally used.
  4. Explain the desirable properties of a good lubricant
  5. What are the various types of combustion chamber used in SI engines? explain them briefly
  6. Write any one type of scavenging pump used in a 2 stroke petrol engine and explain briefly.
  7. Define the following

i)                    Delivery ratio
ii)                  Trapping efficiency
iii)                Relative cylinder charge
iv)                Scavenging efficiency

  1. A gas working on the Otto cycle has a cylinder of diameter 200 mm and stroke 250 m. The clearance volume is 1570 CC. Find the air standard efficiency. Assue Cp= 1.004 KJ/kg K and Cv = 0.7171 KJ/kg K for air.
  2. With a suitable sketches explain the various modern automobiles carburetors
  3. Give brief account of the injection in SI engine
  4. Clearly explain the various Wet sump lubricating system. Compare wet sump and dry sump lubrication
  5. With suitable sketches explain the liquid cooling system of an Automobile.
  6. Explain the phenomenon of knock in SI engine and compare with it with CI engines
  7. Explain various scavenging pumps used in a two stroke engines
  8. what are the advantage and disadvantage of 2 stroke engine
  9. Explain with figures various types of combustion chambers used in SI engines.
  10. With the aid of a circuit diagram explain the working principles of a battery coil ignition system.
  11. Describe the working principles of a centrifugal spark advance mechanism with 
       neat diagram
  1. Describe the necessity of the spark advance mechanism in an engine
  2. With the aid of a diagram describe  vacuum spark advance mechanism
  3. Draw the diagram for an ignition coil and name the components
  4. With the aid of a circuit diagram explain the working principles of a battery coil ignition system.
  5. Describe the working principles of a centrifugal spark advance mechanism with 
       neat diagram
97. Describe the necessity of the spark advance mechanism in an engine
98. With the aid of a diagram describe vacuum spark advance mechanism