Starting Systems

Question 1

How much amperage does a 4 cylinder starter take?

Answer 1

100A

Question 2

How much amperage does a 6 cylinder starter take?

Answer 2

150A

Question 3

How much amperage does a 8 cylinder take?

Answer 3

200A

Question 4

What is the purpose of the starter?

Answer 4

Turns the crank until it can operate on its own

Question 5

What is the average starter to engine gear ratio?

Answer 5

15:1 to 20:1

Question 6

what RPM does the starter pinion gear turn at?

Answer 6

2500rpm to 3000rpm

Question 7

what RPM does the flywheel turn at?

Answer 7

150rpm to 200rpm

Question 8

what is CEMF?

Answer 8

Counter Electromotive Force traveling backwards towards the battery

Question 9

What components are part of the Control Circuit?

Answer 9

Ignition switch, Safety switch, starter relay and battery

Question 10

What components are part of the Starter Circuit?

Answer 10

battery, starter motor and starter solenoid

Question 11

How many amps to pull in the starter solenoid?

Answer 11

35A

Question 12

How many amps to hold in the starter solenoid?

Answer 12

10A

Question 13

what is the preferred test to locate resistance in a starter circuit?

Answer 13

Voltage Drop (Voltmeter)

Question 14

What is the rotating part of a starter called?

Answer 14

The Armature

Question 15

What type of starter motor produces high torque at low RPM, and less as RPM increases?

Answer 15

Series

Question 16

What type of starter motor has less torque at low RPM and higher as RPM increases?

Answer 16

Parallel / Shunt

Question 17

What type of starter motor is able to handle torque at any RPM?

Answer 17

Compound

Question 18

What are the 2 types of starters?

Answer 18

Positive Engagement & Solenoid Actuated

Question 19

What are the 2 main components to an Armature?

Answer 19

windings & commutator

Question 20

What is a Commentator made of?

Answer 20

Heavy copper segments (bars) that are separated from each other by insulation (mica)

Question 21

Newer starter motors may use what kind of gear setup that allows the assembly to be smaller?

Answer 21

planetary gearset

Question 22

What is the component of the armature where it receives its heavy current from?

Answer 22

The Commutator

Question 23

The segments of the commutator should have what type of resistance between themselves?

Answer 23

Low resistance & similar from bar to bar

Question 24

What 3 methods ensure that the pinion gear is able to engage the ring gear smoothly?

Answer 24

Beveled teeth, Spring behind the pinion gear & Bendix drive

Question 25

What could cause a Low current draw?

Answer 25

Undercharged battery

Question 26

What could causes high current draw?

Answer 26

Resistance in the motor

Question 27

What is an maximum Voltage drop across connectors?

Answer 27

0.1v

Question 28

What is an maximum Voltage drop across a Starter relay?

Answer 28

0.3v

Question 29

How do you check the starter drive to ring gear clearance?

Answer 29

feeler gauge or wire, if its less/more then 0.5cm (0.02") it is defective

Question 30

When performing a bench test, what could be the cause of a slow speed/high draw?

Answer 30

Physical resistance (bearings, short in armature, bent armature)

Question 31

When performing a bench test, what could be the cause of no current draw/no crank?

Answer 31

Open in one of the circuits, broken brushes/springs

Question 32

When performing a bench test, what could be the cause of low RPM/low current draw?

Answer 32

High internal resistance (bad connection/brushes)

Question 33

When performing a bench test, what could be the cause of high RPM/high current?

Answer 33

Field windings shorted

Question 34

What should never be used to clean the starter motor and why?

Answer 34

Solvents, the residue left on parts can ignite

Question 35

What should be used to clean the starter motor?

Answer 35

Denatured alcohol or Compressed air (25psi)

Question 36

what is a cranking voltage test, and how do you perform it?

Answer 36

Measures the available Voltage to the starter during cranking. it is performed by disabling the fuel or bypassing the ignition switch and connecting a Voltmeter to ground and starter feed. activate the starter and observe that the voltage has a minimum of 9.6v

Question 37

what is a cranking current test, and how do you perform it?

Answer 37

Measures the amount of current the starter draws to crank the engine. it is performed by using a Inductive pickup clamp. Disable fuel and crank the engine for max 15sec and observe that the amperage is around 130A to 250A (depending on engine size)