AuTo inFo_ [MUST READ]

 IMPORTANT

• The aspect ratio (expressed in percentage) of the tyre is defined as the ratio of section height to section width
• If a tyre is designated as 175/65 R14 82 S, then the aspect ratio for the tyre is 65
• The piston compression rings are made of cast iron
• In order to implement gear changes in the gear unit of an automatic transmission, a hydraulic multi plate clutch is used
• When the brake pedal free play is less than the specified value, then the brake drags
• The seat belt will move out smoothly when pulled out slowly, but it will lock when pulled quickly
• The boiling point of Diesel fuel is in the range of180°C to 360 °C
• The component in the radiator of an automobile that increases the boiling point of water is pressure cap
• The temperature indicating instrument in vehicles indicates the temperature of jacket cooling water
• The process of removing the burnt gases from the engine cylinder by the fresh charge coming into the engine cylinder from the crank-case, is known as scavenging
• The process of supplying the intake air to the engine cylinder at a pressure greater than the pressure of the surrounding atmosphere is known as supercharging
•  In aluminium cylinder blocks, the cylinder liners are made of CI
• Free pedal play in car clutches is about  25 mm
• The caster is called positive when the top of the king pin is inclined to the  rear of the vehicle
• The main function of a master cylinder is to convert brake pedal force into hydraulic pressure
• The effect of vapour locking on the brake performance is that the brakes fail completely
• Clutch facings are usually attached to the plate by brass rivets
• The firing order for an opposed four cylinder l.C. engine is 1-4-3-2
• The function of positive crankcase ventilation (PCV) system is that it returns blow-by gases from the crankcase to the intake system
• The maximum torque multiplication ratio in a torque converter is about 2.5
• The sequence in which the force is transmitted through a brake system when the brake pedal is depressed is  : brake pedal - vacuum servo mechanism - master cylinder - brake lines - brake pads
• The main function of an exhaust muffler is the reduction of exhaust noise
• The purpose of transmission in an automobile is to vary the torque at the wheel
• Caster is a forward tilt of the kingpin OR backward tilt of the kingpin
• A front stabilizer bar is used to control suspension movement and body roll
•  When the front wheels of a vehicle are locked during braking, then driver loses control over the steering, and the vehicle continues moving in its current direction
• The order in which effort applied to the steering wheel is transferred to the front wheel is steering wheel - steering shaft - steering gearbox - tie rod - steering kunckle -front wheels
• The best fuels for compression ignition engines are napthalenes
• The main function of a resonator is that it reduces the intake air noise
• For the same maximum pressure and temperature Diesel cycle is more efficient than Otto cycle
• The lower cylindrical portion of the piston which improves piston cooling performance is called piston skirt
• The tyre rotation is generally done at 10000km
• The included angle is the sum of the camber and S.A.I.
• Toe can be adjusted by modifying the tie-rod attachment length 
• The main feature of MacPherson strut suspension is that non-vertical external forces are supported by the suspension arms
• The fuel pump in the programmed fuel injection (PFI) system is located in fuel tank
• The materials used for cylinder block are cast iron and aluminium alloy
• The capacity of a battery is usually expressed in terms of ampere-hours
• Vulcanizing means heating rubber under pressure
• The correct way to rectify an imbalanced wheel is to attach appropriate weights to the wheel at appropriate positions
• The crankcase dilution means dilution of lubrication oil by fuel in the crankcase
• Engine misfiring is likely to result from spark plug gap too wide
• The brake pedal during ABS operation transmits slight kickback to the driver's foot
• The gear shift lever requires two separate motions to shift gears, and the first movement selects the synchronizer 
• Two speed reverse gear arrangement is generally provided in case of tractors
• Odometer is an instrument used for measurement of distance
• Wheel base of a vehicle is the distance between the centres of the front and rear wheels
• In Diesel engines, the duration between the time of injection and the time of ignition is called delay period
• In a single dry plate clutch, torsional vibrations are absorbed by coil springs known as torsional springs
• Cushioning springs in clutch plate reduces jerky starts
• Toe-in ensures parallel rolling of the wheel thus stabilizing steering in addition to preventing both sides slipping and excessive tyre wear.
• Highest useful compression ratio (HUCR) is the highest compression ratio at which the fuel can be used in a test engine without knocking
• The function of a governor in automobiles is to limit the vehicle speed
• Bead wires are made of steel
• A maintenance free battery has lead-calcium plate grid
• The Diesel engines as compared to petrol engines require bigger flywheel
• In a forced feed lubrication system, the device used to guard against excessive oil pressure, is known as relief valve