If the air-fuel mixture in a spark ignition engine is too rich, then airfuel ratio is about
17 : 1
15 : 1
13 : 1
10 : 1
Correct Answer :
D. 10 : 1
Related Questions
The parking brakes employed in vehicles are operated
Mechanically
Hydraulically
Pneumatically
None of these
In a four stroke engine for each crankshaft revolution, the camshaft revolves
One half turn
One turn
Two turns
Four turns
The information provided by the oxygen (O₂) sensor to the feedback control system is about the
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Air temperature
Air flow speed
Exhaust gas volume
The basic characteristics of a brake fluid is
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Compatibility with rubber and metal parts
All of these
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Increases the combustion temperature
Creates swirl
Maintains a seal and prevents the fuel leakage
Maintains a seal and prevents escape of burned gases and loss of pressure in the combustion chamber
The crankcase dilution means
Dilution of fuel in the crankcase
Dilution of oil by water in the crankcase
Dilution of lubrication oil by fuel in the crankcase
Dilution of mixture passing through crankcase in two stroke engines
A heat treated glass generally used in automobiles bursts into ________ upon cracking,
Sharp edged fragments
Small particles
Large particles
None of these
The compression ratio for Diesel engines usually lies in the range of
6-10
10-1
15-25
25-40
The condition that results in large quantities of CO emission is
Insufficient air during combustion
Insufficient fuel during combustion
Low temperature combustion
High temperature combustion
The damper fluid leakage typically occur from
Upper damper mounting
Bottom of damper
Clearance between inner and outer tubes of damper
Coil spring mounting
The main characteristics of a maintenance free (MF) battery is that
A maintenance free battery requires little maintenance during normal use and it is sufficient to add water instead of an electrolyte containing sulphuric acid
A maintenance free battery has a relatively short shelf life when compared with standard batteries
Since it is sealed, the water in maintenance free battery is not lost through evaporation thus accordingly it is not necessary to top up the cells with water
Recharging of a maintenance free battery is neither required nor possible
The connecting rods are generally made of ________ shaped crosssection.
I
C
L
H
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Suction exhaust power compression
Suction power compression exhaust
Suction compression power exhaust
Exhaust compression power suction
The clutch is located between the transmission and the
Engine
Rear axle
Propeller shaft
Differential
The boiling point of Diesel fuel is in the range of
70°C to 100°C
100°C to 120°C
120°C to 180°C
180°C to 360 °C
Which one of the following statements correctly describes the construction of a planetary gear type differential?
The six planetary pinions rotate in constant mesh with the internal gears.
One drive shaft is splined to the central gear and the other to the planetary gear.
Each planetary pinion gear meshes with both the central gear and the internal gear.
The internal gear is fixed to the planetary gear.
When the brake pedal free play is less than the specified value, then the
Brake drags
Brake fades
Vapour locking occurs in the brake lines
Antilock braking system malfunctions
The purpose of turning radius gauges is to measure the
Contact areas of the tyres
Free plays of the steering wheel
Turning radius of the left and right wheels
Difference in the toe angles of the left and right wheels
In a ventilated disc brake
A duct directs air towards the caliper for cooling while the vehicle is moving
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Disc contains many small holes for optimum cooling performance
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C8H18
C7H17
C6H18
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Engineering scale
Feeler gauge
Vernier caliper
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Iso-octane
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Compression ignition (C.I.) engines
Steam engines
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Distributor
Radiator fan pulley
Alternator pulley
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Head light bulb
Stop light bulb
Parking light bulb
Ignition warning bulb
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Prevent engine oil from going into combustion chamber
Removes impurities from cylinder head lubricating oil
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Air and fuel
Only fuel
Only air
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60°
90°
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Camber
Caster
Toe
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Step up current
Step down current
Step up voltage
Step down voltage