Explore topic-wise MCQs in Automobile Engineering.

This section includes 315 Mcqs, each offering curated multiple-choice questions to sharpen your Automobile Engineering knowledge and support exam preparation. Choose a topic below to get started.

101.

In the cam the distance between the base circle and the nose is called

A. Displacement
B. Lift
C. Flank
D. Lobe
E. Nose
Answer» C. Flank
102.

Which air cleaner is considered to be most effective in Diesel engines?

A. All are equally effective
B. Whirl type
C. Oil bath type
D. Wet type
E. Dry type
Answer» D. Wet type
103.

If the water level in engine is maintained low, the likely consequence could be

A. Piston seizure
B. Engine knocking
C. Bearing deterioration
D. All of the above
E. None of the above
Answer» E. None of the above
104.

The number of plies in a truck tyre is usually

A. 2
B. 5--8
C. 8--10
D. 3
E. 12--16
Answer» F.
105.

Which one of the followings is used in C.I. engines?

A. spark plug
B. injector
C. cross-head
D. none of the above
E. None of the above
Answer» C. cross-head
106.

Cross wire grooves on tyres

A. Absorb shocks due to road unevenness
B. Lessen the danger of skidding
C. Provide good traction
D. Provide better load carrying capacity
E. Secure better steering properties
Answer» B. Lessen the danger of skidding
107.

In case of clutch if the springs become weak, the remedy lies in

A. Tightening further the springs
B. Interchanging the springs
C. Retempering the springs
D. Replacing the springs
E. Any of the above
Answer» E. Any of the above
108.

In a petrol engine, the gas which does not burn and passes out without transformation is

A. Oxygen
B. Carbondioxide
C. Nitrogen
D. Carbon monoxide
E. Water vapour
Answer» D. Carbon monoxide
109.

The size of the engine intake valve is

A. Same as that of exhaust valve
B. Depends upon the temperature of ambient air.
C. Does not depends upon the size of the exhaust valve
D. Smaller than that of exhaust valve
E. Large than that of exhaust valve
Answer» E. Large than that of exhaust valve
110.

Which region of an automobile tyre is subjected to greatest flexing action?

A. Bead
B. Side wall
C. Shoulder
D. Tread
E. None of the above
Answer» C. Shoulder
111.

At the first sight a petrol engine is identified by

A. Size of air cleaner
B. Cylinder size
C. Spark plug
D. Power output
E. Operating speed
Answer» D. Power output
112.

The inlet value of a four stroke I.C. engine, in actual practice, should close

A. exactly at the end of suction stroke
B. slightly after the end of suction stroke
C. slightly before the end of suction stroke
D. none of the above
E. None of the above
Answer» C. slightly before the end of suction stroke
113.

Failure of an engine to start even though it turns over at normal cranking speed could be due to

A. A defective cranking motor
B. Defective ignition
C. Run down battery
D. Sticking valve
E. Low ambient temperature
Answer» C. Run down battery
114.

1000 mm diameter tyre is generally used on

A. Scooters
B. Jeeps
C. Motorcycles
D. Trucks
E. Mopads
Answer» E. Mopads
115.

Ignition system used in scooters is

A. magneto system
B. battery system
C. Combination of magneto and battery system
D. neither magneto nor battery system
E. None of the above
Answer» B. battery system
116.

In case of four cylinder opposed cylinder engines, the firing order is

A. 1-2-4-3
B. 1-2-3-4
C. 1-4-3-2
D. 1-2-4-2
E. 1-3-2-4
Answer» D. 1-2-4-2
117.

Magneto ignition system is used in

A. S.I. engines
B. C.I. engines
C. Steam engines
D. none of the above
E. None of the above
Answer» B. C.I. engines
118.

To avoid chances of maisalignment the bearing generally used is

A. Double row ball bearing
B. Axial bearing
C. Self-aligning bearing
D. Taper roller bearing
E. Radial bearing
Answer» E. Radial bearing
119.

Automobiles in India generally do not use battery with a voltage of

A. 6 volts
B. 12 volts
C. 18 volts
D. 24 volts
E. Any of the above
Answer» D. 24 volts
120.

Increasing the temperature of intake air in an I.C. engine will

A. increase the efficiency
B. decrease the efficiency
C. increase or decrease the efficiency
D. None of the above
E. Low ambient temperature
Answer» C. increase or decrease the efficiency
121.

The function of condenser in the ignition circuit of an SI engine is

A. to interrupt the battery current
B. to enhance the circuit voltage
C. to avoid arcing at the contact breaker and to cause faster decay of primary current
D. none of the above
E. None of the above
Answer» D. none of the above
122.

Which one of the following is the trouble due to clutch?

A. Dragging
B. Rattling
C. Slipping
D. Grabbing
E. All of the above
Answer» F.
123.

The phenomenon by which a fuel catches fire without external flame is known as

A. pre-ignition
B. detonation
C. ignition lag
D. auto-ignition
E. None of the above
Answer» E. None of the above
124.

The knocking in C.I. engine can be prevented if the first element of the fuel and air is having

A. low density
B. medium density
C. high density
D. none of the above
E. None of the above
Answer» D. none of the above
125.

Driving wheel hearings in automobiles are always

A. Bush bearing
B. Clad metal bearings
C. Anti-friction bearings
D. Either (A) or (B)
E. Either (B) or (C)
Answer» D. Either (A) or (B)
126.

Morse Test in multicylinders is used to determine

A. Air flow to engine
B. Mechanical efficiency
C. Volumetric efficiency
D. BHP
E. IHP
Answer» C. Volumetric efficiency
127.

The level of electroyte in automobiles battery should be

A. Exactly at the level of the plates
B. 15 mm below the top of plates
C. 5 - 10 mm below the top of plates
D. Upto the maximum permissible level
E. 10 - 15 mm above top of plates
Answer» F.
128.

In a diesel engine a clogged nozzle could result in

A. Excessive fuel consumption
B. Over-rich mixture
C. Excessive smoke
D. Failure to start
E. Any of the above
Answer» F.
129.

Ignition coil is used to

A. Step down voltage
B. Step up power
C. Step down current
D. Step up voltage
E. Step up current
Answer» E. Step up current
130.

The knocking in S.I. engines is characterised by sudden auto-ignition of the change

A. nearest to the spark plug
B. farthest away from the spark plug
C. in the middle from the spark plug
D. none of the above
E. None of the above
Answer» C. in the middle from the spark plug
131.

The device in the cooling system that increses the boiling point of the water in the system is called

A. Drain plug
B. Pressure cap
C. Radiator
D. Water jacket
E. Vacuum valve
Answer» C. Radiator
132.

For a spark plug M 14 x 1.25 the last figure 1.25 stands for

A. Gap between electrodes in mm
B. Pitch of plug thread
C. Electrode diameter in mm
D. Tip width in mm
E. Size of plug thread
Answer» C. Electrode diameter in mm
133.

The exhaust value remains open approximately for

A. 160?
B. 180?
C. 190?
D. 235?
E. None of the above
Answer» E. None of the above
134.

Two SI engines run at same speed and develop same power but have different compression ratio. The engine with higher compression ratio will have its ignition advance

A. more than
B. less than
C. equal to
D. none of the above
E. None of the above
Answer» C. equal to
135.

Exhaust gas leakage into the cooling system is most likely be due to defective

A. Cylinder head gasket
B. Manifold gasket
C. Water pump
D. Radiator
E. Any of the above
Answer» B. Manifold gasket
136.

Poor compression in a two stroke engine cannot be due to

A. Leaky valves
B. Broken piston rings
C. Leaking cylinder head gasket
D. Poor fits between pistons, rings and cylinders
E. Any of the above
Answer» B. Broken piston rings
137.

As the number of cylinders on multi-cylinder engines increases the power to weight ratio

A. Has nothing to do with number of cylinders
B. Decreases
C. Increases
D. Remains the same
E. Becomes zero
Answer» C. Increases
138.

In which case the air fuel ratio is expected to be the highest?

A. Two stroke petrol engine
B. Gas turbine
C. Four stroke diesel engine
D. Two stroke diesel engine
E. Four stroke petrol engine
Answer» C. Four stroke diesel engine
139.

In case of petrol engine, pre-ignition of the charge during compression stroke is

A. not possible
B. possible
C. possible during power stroke
D. none of the above
E. None of the above
Answer» C. possible during power stroke
140.

For lubrication of which part of an automobile only grease is used

A. Transmission
B. Steering system
C. Axle drive
D. Tie rod
E. All of the above
Answer» E. All of the above
141.

Which fuel has maximum resistance to detonation

A. n-heptane
B. Toluene
C. Isoctave
D. Benzene
E. Alcohol
Answer» D. Benzene
142.

Loss of engine compression can result from

A. Wrong timing
B. Defective fan belt
C. Worn out rings
D. Excessive tappet clearance
E. Excessive tappet clearance
Answer» D. Excessive tappet clearance
143.

The heating value of petrol is

A. 7650 kcal/kg
B. 10,000-10400 kcal/kg
C. 15000-16000 kcal/kg
D. 8000-8500 kcal/kg
E. 12750-13850 kcal/kg
Answer» C. 15000-16000 kcal/kg
144.

The breaking up of a liquid into fine droplets by spraying is called

A. Injection
B. Vaporization
C. Atomisation
D. Ionisation
E. Carburetion
Answer» D. Ionisation
145.

Odometer is

A. An instrument which indicates the condition of the battery
B. An instrument for distance measurement
C. An instrument for BHP measurement
D. An instrument for smoke analysis
E. An instrument used for measurement of fuel consumption
Answer» C. An instrument for BHP measurement
146.

If the end mixture of S.I. engine is having low temperature and long igition delay, then knocking will

A. accelerate
B. decrease
C. remain constant
D. none of the above
E. None of the above
Answer» C. remain constant
147.

If the cut-off is decreased, the efficiency of Diesel cycle

A. is equal to Otto cycle
B. is more than Otto cycle
C. is less than Otto cycle
D. approaches to Otto cycle
E. None of the above
Answer» E. None of the above
148.

Which one of the following is independent of fuel constituents, combustion chamber design, temperature and pressure of compressed charge

A. Pinking
B. Pre-ignition
C. Knocking
D. none of the above
E. None of the above
Answer» C. Knocking
149.

Which company is not engaged in the manufacture of tyres in India

A. Larsen & Toubro
B. Appollo
C. Modi
D. Good year
E. J.K.
Answer» C. Modi
150.

The tendency of a petrol engine to knock increases by

A. Turbo-charging
B. Cataytic converter
C. Alcohol
D. Addition of lead
E. Super-charging
Answer» B. Cataytic converter