Basic Automotive Engine Auxiliary Systems Questions and Answers on “Starting System”.
1. What is the voltage required for starting a car engine?
a) 12V
b) 9W
c) 24V
d) 32V
Answer: a
Clarification: The rated voltage for the starting system, which is 12V in case of a car engine and 24V for heavy vehicle engines. Car engine parts require less power to move. Hence, 12V is used.
2. What is the voltage required for starting a heavy vehicle engine?
a) 12V
b) 9W
c) 24V
d) 32V
Answer: c
Clarification: The rated voltage for the starting system, which is 12V in case of a car engine and 24V for heavy vehicle engines. Heavy vehicle engine parts require a lot of power to move. Hence, 24V is required.
3. In cars, what is the lowest temperature at which the car engine may be started?
a) -15°C to -20°C
b) -18°C to -25°C
c) 8°C to 25°C
d) -8°C to -5°C
Answer: b
Clarification: 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.
4. Calculate the total number of turns for a square and ground end when N=13?
a) -15°C to -20°C
b) -18°C to -25°C
c) 8°C to 25°C
d) -8°C to -5°C
Answer: a
Clarification: The lowest temperature at which the car engine may be started is usually taken as -18oC to -25oC for cars and -15oC to -20oC for heavy transport vehicles.
5. Which of the mentioned below is not a component of a starting motor?
a) Armature
b) Commuter
c) Field windings
d) Battery
Answer: d
Clarification: 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.
6. Most of the automotive starting motors have how many poles?
a) 3
b) 4
c) 5
d) 6
Answer: b
Clarification: 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.
7. Most of the automotive starting motors have how many brushes?
a) 3
b) 4
c) 5
d) 6
Answer: b
Clarification: 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.
8. What is the starting torque of the starting motor for a light and medium car?
a) 10 to 30Nm
b) 50-150Nm
c) 40 to 15Nm
d) 5 to 10Nm
Answer: a
Clarification: 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.
9. What is the starting torque of the starting motor for heavy vehicles?
a) 10 to 30Nm
b) 50-150Nm
c) 40 to 15Nm
d) 5 to 10Nm
Answer: b
Clarification: 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.
10. What is the minimum cranking speed required for starting an engine in the winter condition?
a) 100rps
b) 10rpm
c) 100rpm
d) 50rps
Answer: c
Clarification: 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.
11. On what factor, the speed ratio between the starting motor and the crankshaft is depended?
a) Teeth on flywheel
b) Piston
c) Size of flywheel
d) Crankshaft
Answer: c
Clarification: 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.
12. On what factors, the starting torque is dependent?
a) Piston displacement per cylinder
b) Number of cylinders
c) All of the mentioned
d) Compression pressure
Answer: c
Clarification: 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.
13. What is the highest current that is drawn by the starter motor?
a) 50amps
b) 230amps
c) 500amps
d) 1000amps
Answer: c
Clarification: 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.
