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Right option is (C) Open circuit in the FIELD winding

For explanation: This problem is due to the open circuit, the WIRING of every component has to be TESTED INDIVIDUALLY and the defective component has to be replaced.

The correct answer is (C) Belt DRIVE or connected directly to the flywheel

To explain: It can be the belt-driven or connected directly to the flywheel between the ENGINE and the gearbox. The FORMER needs less amount of copper and iron.

The CORRECT choice is (C) PERMANENT magnet

The best explanation: In MODERN starters, the conventional field windings and the pole SHOES are replaced with permanent magnets. Hence permanent magnets are the right answer.

Right OPTION is (B) Voltmeter

Best explanation: The device USED to CHECK the voltage is the voltmeter and the device used to check the speed is the ODOMETER, the device used to check the RPM is the tachometer.

Correct answer is (b) LOOSE connection

The best I can explain: This is due to some loose connection in the circuit, most likely near the battery. This may be LOCATED and RECTIFIED accordingly by TIGHTENING the NUT and checking the wire.

Right answer is (B) Light

To elaborate: The LIGHTS in the car are USED to indicate the working condition of the starter MOTOR, lights may GO off, it might get dim or it is unaffected all this indicates the problem of the starter motor.

Correct choice is (d) 10-15seconds

To EXPLAIN I would say: In the case of shift, it must be noted that the test should not be CONTINUED for more than 10-15 seconds. DISCONNECT the LEAD wire connecting the switch to the STARTER motor.

The correct CHOICE is (b) Multimeter

The explanation: CONTINUITY should EXIST in the field windings which may be tested with a multimeter. There should also be perfect INSULATION between the yoke and the field.

Correct ANSWER is (a) Replace the brushes

For explanation I WOULD say: EXAMINE the brushes visually for wear and damage, if the wear or damage is more than the permissible limits, replace the CONCERNED brushes.

Right choice is (a) Ammeter

To elaborate: The device USED to check the CURRENT is the ammeter and the device used to check the voltage is the voltmeter, the GALVANOMETER is used to detect and indicate ELECTRIC current.

Right option is (a) 150-180rpm

Explanation: The minimum cranking SPEED for a RECIPROCATING S.I ENGINE is 60-90rpm, for the rotary engine it is 150-180rpm. Rotary engines are the high-speed engine that are rarely used in RACE cars.

The correct choice is (C) 60-90rpm

Easy explanation: The MINIMUM CRANKING speed for a reciprocating S.I ENGINE is 60-90rpm, for the rotary engine it is 60-90rpm and for the C.I engine with glow plugs is 60-140rpm.

Correct choice is (C) Battery VOLTAGE

The EXPLANATION is: The relay CIRCUIT through the generator provides protection against the operating of the starter while the engine is running because the generator voltage is approximately equal to Battery voltage.

Correct OPTION is (B) To control solenoid currents

The best explanation: The relay used to control the solenoid currents. Further, completing the relay circuit through the GENERATOR PROVIDES PROTECTION against the operating of the starter.

Right option is (a) 2

For explanation I would say: The solenoid SWITCH come-shift has got a different plunger construction suited for operating the shift lever. Further, this is of 2 winding types, the solenoid shift MUST always have two windings.

The correct answer is (b) Less current drawn from the BATTERY

Best explanation: The advantage of the solenoid SWITCH is it draws less current in Hold-in WINDING when it remains to hold the contacts closed. Hence, Less current drawn from the battery is the right answer.

Correct choice is (b) Armature

For explanation: The solenoid SWITCHES have TWO winding, pull-in, and hold-in windings. Both the windings exert COMBINED FORCE to pull the armature.

The correct answer is (d) Solenoid switch

Explanation: The advantage of the solenoid switch when compared to MANUAL switch is that the heavy current wiring length is reduced, which REDUCES the VOLTAGE drop.

Correct option is (d) All of the mentioned

To explain: Here the plunger is pressed to make contacts and contacts are made by hand, foot, ACCELERATOR lever. Manual switches are LESS dangerous than electronic switches in the condition of SUDDEN POWER failure.

Correct ANSWER is (C) Pinion

To elaborate: The shell is CONNECTED with the ARMATURE shaft through splines and the collar is attached to Pinion of the starting motor to start the VEHICLES.

The correct answer is (C) ANGULAR motion

Best explanation: When the shift sleeve is pushed to the right and CONSEQUENTLY the pinion is also moved in that direction, because of the spiral TEETH, there is angular motion.

The correct CHOICE is (b) Rubber spring

Best explanation: Rubber spring Bendix DRIVE is used to avoid the damage caused due to false ENGINE starting the PISTON gets disengaged and an attempt is made to BRING it back.

The correct answer is (b) Armature shaft

For explanation: When the MOTOR is started, the sleeve STARTS ROTATING ALONG with the armature shaft of the motor. A spring under compression is employed in between the sleeve and the nut which is fixed on the END of the armature shaft.

The CORRECT CHOICE is (a) Flywheel

To explain I would say: When the pinion gear starts to ROTATE, it is offered by an internal resistance by the flywheel which is stationary when the VEHICLE is in a standstill position.

Right choice is (a) Shaft

The EXPLANATION is: The SLEEVE can slide or turn freely over the shaft of the motor and the shaft is KEYED to the FIXED down head which is connected torsionally to the sleeve through a COIL spring.

Correct choice is (b) TOWARDS

The best I can explain: Inboard and outboard are the two types of Bendix drives. In the outboard type PINION moves away from the STARTING motor to ENGAGE the FLYWHEEL whereas in the inboard type it moves towards the starting motor.

The CORRECT OPTION is (c) Away

The best I can explain: INBOARD and outboard are the two types of Bendix drives. In the outboard type pinion MOVES away from the starting motor to ENGAGE the flywheel whereas in the inboard type it moves towards the starting motor.

The correct answer is (c) 500amps

To EXPLAIN: The starter MOTOR is DIRECTLY connected to the battery from where it draws the current for its operation. The AMOUNT of current DRAWN for starting may be as high as 500amperes.

Correct choice is (b) 50-150Nm

For explanation I WOULD say: For light and medium cars, the starter motors of starting 10 to 30Nm are employed, WHEREAS for larger cars and HEAVY vehicles the starting torques required are 50 to 150Nm. Heavy vehicle engines have heavier COMPONENTS. Hence, to MOVE them higher torque is required.

Right answer is (c) All of the mentioned

Explanation: The starting TORQUE of the STARTER motor DEPENDS on PISTON displacement per cylinder, number of cylinders, and the Compression pressure. HENCE, all of the mentioned is the right answer.

The CORRECT answer is (C) Size of flywheel

For EXPLANATION: The speed ratio between the starting motor and the crankshaft DEPENDS on the Size of the flywheel, which is further DICTATED by engine design consideration.

Correct option is (c) 100rpm

The best explanation: It is found that on the modern car engine the minimum cranking SPEED of 100rpm is adequate EVEN in adverse WINTER conditions. Hence, 100rpm is the right ANSWER.

Right option is (B) 4

To explain I would say: Most of the automotive starting motors have 4 poles and 4 brushes. The brushes are HELD against the commuter using springs. The brushes depend on the power and WINDING of the motor.

The correct ANSWER is (b) 4

Best explanation: Most of the automotive starting motors have 4 poles and 4 BRUSHES. The brushes are held against the commuter USING springs. Pole refers to the north or south pole of the MAGNET.

Right choice is (d) Battery

Easy explanation: The MAIN components of a starting motor are the body, the armature, the commuter, and the FIELD winding. Whereas battery is a separate component USED as a power source for the motor.

Correct ANSWER is (a) -15°C to -20°C

The BEST I can explain: The lowest TEMPERATURE at which the car engine may be started is usually taken as -18^oC to -25^oC for CARS and -15^oC to -20^oC for heavy TRANSPORT vehicles.

Correct option is (b) -18°C to -25°C

The EXPLANATION is: The lowest temperature at which the CAR engine may be started is usually taken as -18°C to -25°C for CARS and-15°C to -20°C for heavy transport vehicles. The lowest temperature Includes the snowy REGIONS.