1. l.c engines are those engines where fuel is burnt —
a) Inside the combustion chamber
b) Outside the combustion chamber
c) Inside the induction manifold d) Inside tho exhaust manifold

In a four stroke engine how many power stroke is / are available in two revolutions of crank   shaft?
a) Four
b) Three
c) Two
d) One

In petrol or gas engine the fuel is ignited by
a) Spark from electric spark plug
b) Igniter plug
c) The heat of compressed air
d) The hot exhaust

The diesel engine is also known as —
a) S.I. engine
b) C.I. engine
c) Steam engine
d) Boiler

The "Clearance volume" is the volume of the cylinder above the piston when piston is at —
a) TDC
b) BDC
c) In between TDC and BDC
d) None of the above

To find out the RPM of an engineis used.
a) Tachometer
b) Ammeter
c) Odometer
d) Trip - Odometer

In petrol engine the compression ratio range is —
a)13 to 15 :
b) 8 to 12 : 1
c) 16 to 20
d) 21 to 25 : I

T   Slot is provided in the piston —
a) For the passage of lubricating oil
b) For cooling purpose
c) To accommodate the expansion of piston when heated up.
d) None of the above

The material of crank shaft is
a) High carbon steel
b) Cast iron
c) Alluminium alloy
d) Copper

The function of connecting rod is to
a) Transmit the piston motion to the crankshaft
b) Turn the flywheel
c) Turn the fuel pump
d) Turn the drive plate

In a 4 — stroke diesel engine the fuel is injected into the combustion chamber at the end of stroke-
a) Suction
b) Compression
c) Power
d) Exhaust

Which is the hottest portion of the poppet valve during operation in I-C. engine?
a) Valve face
b) Valve head
c) Valve stem
d) Valve neck

The period in crank angle at which both inlet and exhaust valves remains in open position at the  end of exhaust and beginning of induction stroke is called
a) Valve lead
b) Valve lag
c) Valve overlap
d) Valve throw

Generally in 4-stroke diesel engine the inlet valve opens —
a) 100 before TDC
b) 20 0 before TDC
c) 30 0 before TDC
d) 400 before TDC

The diesel fuel is rated by
a) Octane number
b) Cetane number
c) Flash point
d) Fire point

For water cooled engine generally the butt gap of piston ring 0.12 mm. is provided for every
 mm. bore diarneter.
c) 20 d) 25
17. When the gudgeon pin (piston pin ) is free, both in piston bosses as well as in small end of the  connecting rod, the type of locking method of piston pin is called   a) Semi — floating b) 'Three quarter floating

c) Free pin d) Fully Floating

Which type of cylinder liner outer surface does not have direct contact with liquid coolant or water?
a) Dry liner
b) Wet liner
c) Semi wet liner
d) None of these

Disadvantage of Pre combustion chamber is
a) Power loss
b) Problem of leakage of change
c) Cold starting problem
d) None of these

Firing order of a 6 — cylinder engine is
a) 1-6-4*3-5-2
b) 1-3-6-2-5-4
c) 1-5-3-604
d) 14-2-5-3-6

The function of flywheel is to
a) Maintain the speed of crank shaft
b) Transmit the engine power to the transmission system
c) Start the engine with the help of starter ring fitted on it
d) All of the above

For fitting piston rings in grooves the tool is used — p
a) Piston ring expander
b) Piston ring compressor
c) Piston ring filer
d) Screw Driver

The working pressure of low pressure lubrication system is

a) Up to 5 Kg/cm
b) Up to 4 Kg./cm2
c) Up to 3 Kg./cm2
d) Up to 1.5 Kg./cm2

Radiator pressure cap is fitted to
a) Reduce boiling point of water
b) Increase boiling point of water by increasing pressure
c) Reduce the overflow of water
d) Reduce pressure

The temperature at which the thermostat valve opens maximum is
a) 55 0 C
b) 60 65 0C
c) 70 - 75 0 c
d) 80 85 0c

The disadvantage of air cooling system is —
a) Effciency is lower than water cooling system
b) Working temperature remains high
c) Heat removal rate highly depends on the atmospheric temperature.
d) All ofthe above

The function of injector is to inject fuel to the combustion chamber in —
a) Droplet form
b) Atomized form
c) Liquid form
d) Any form

The advantage of dry gump lubrication system is
a) It reduces the engine height
b) Better lubrication
c) The system is cheap
d) Less quantity of oil required

Oil pressure relief valve is fitted to —
a) Oil sump
b) Main oil gallery
c) Oil pump
d) Oil strainer

The super charger is called Turbo charger when the turbine of the super charger  is driven by
a) Engine power
b) Exhaust gases of engine
c) AC 230 volts supply
d) Vehicle battery
a) Governor b) Injector
c) Camshaft of FIP d) None of these

Plunger type fuel feed pump of diesel engine is operated by —

The full form of CRDI is -
a) Common Rail Direct Injection
b) Common Rail Diesel Injection
c) Common Rate Diesel Injection d) Common Rate Direct Injection

Engine which are used for electric Generator is called —
a) High speed engine
b) Low speed engine
c) Variable speed engine
d) Constant speed engine

Which one of the following toxic components of exhaust gas separates oxygen in three way catalytic converter?
a) CO
b) HC
c) NOX
d) N2

IvVhich one of the toxic component is reduced by an EGR system?
a) NOX
c) HC d) CO
36. Starter motor runs but pinion does not engage with ring gear of fly wheel the probable cause is —
c) Defective splines
37. Loss of compression may cause — Any one of the above
  a) Excessive fuel consumption b) Noisy Engine
c) Engine back fires d) Smoky exhaust
a) Worn out pinion teeth b) Worn out teeth of ring gear

38. "The engine is noisy" the probable cause is —
a) Use of low octane fuel b) Loose piston pin
 c) Broken piston ring jd) Any one of the above
39. What is the full form of SAE?
a) Special Automobile Engine B) Society of Automotive Engineers
c) Society of Automotive Engines d) None of these
 40. Which of the following multi grade oil is used in modern car engine?

J SAE 20w 40 b) SAE - 20W30  c) SAE 30W40 d) SAE - 40W50
41. Which type of oil pump is generally fitted in light car engines?
a)/ Gear type b) Reciprocating
c) Electic type d) Any one of these

42. Most commonly used water / liquid cooling system is —
a) Thermo Syphon System b) Impeller thermo syphon system
p) Pump Circulation System d) Any one of the above
43. For a given size of engine, the power output, with super charger is able to increase by
a) 20-30 b) 30 — 40
c) 40 - 50 d) 50 - 60
44. In oil bath air cleaner which oil is used?
pa) Engine oil b) Gear oil

c) Brake oil d) Spindle oil
45. Ignition warning lamp does not light even after switching on the ignition key, the probable cause is —
a) Lamp bulb burnt out
b) Fuse blown off
c) Open circuit between lamp and Ignition switch  Any one of the above
46. Which of the following is not a component of charging circuit?

a) Battery b) Starter solenoid
c) Generator d) Ammeter
47. Alternating current produced by alternator is converted to Direct current with the help of

a) Transistor b) Commutators
 p) Rectifier d) Condensers
48. When the charging system is fitted with alternator then which component is blocking the reverse flow of current from the battery?
,a) Rectifier diodes b) Cut out
c) Voltage regulator d) Current regulator
49. Which of the following is not the cause of "engine over heating"?
a) Lack of coolant wb) Wheel wobble

c) Defective water pump d) Insufficient engine

 Which of the toxic component will cause dizziness?
a) NOX
c) HC A) co

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