MAINTENEANCE AND REPAIR OF STARTING SYSTEMS TOPIC 5

OBJECTIVES Explain the operation of the starting system Perform a starter check on a vehicle Perform basic maintenance on the motor of a starter.

Staring System Principles Starting system uses battery power and an electric motor to crank the engine for starting,

EXPLAIN THE OPERATION OF THE STARTING SYSTEM SO 5.1 EXPLAIN THE OPERATION OF THE STARTING SYSTEM 5.1.1 Explain safety procedures when working on a starter 5.1.2 Explain the different types of starter motors 5.1.3 Describe the electric circuit. 5.1.4Explain the components of the starter motor.

Explain safety procedures when working on a starter SO 5.1.1 Explain safety procedures when working on a starter The main safety precaution when working on a starter is to; Switch off the ignition? Remove wire from starter solenoid? Disconnect the battery? Wear appropriate PPE?

Explain the different types of starter motors 5.1.2 Explain the different types of starter motors Starters are classified by the type of pinion gear engagement, Two Types: Moveable pole shoe starter A lever moves the pinion towards the ring gear Solenoid starter motor Solenoid creates a magnetic field pulls on the pinion gear to engage with the ring gear

STARTING SYSTEM Question 1. Explain the main safety precaution when working on the starter system. Name two types of starters. Explain the difference between these starters.

Describe the electric circuit. SO 5.1.3 Describe the electric circuit. Circuit components: Battery Battery cable Switch Starter housing Armature Field coils Solenoid

Describe the electric circuit. continue SO 5.1.3 Describe the electric circuit. continue Battery- Source of electric energy Battery cable- link battery and starter solenoid Switch- Activate the starter system Starter housing- Holds the armature, brushes, field coils and armature bearings. Armature- High torque turning power Field coils- Create a strong magnetic field to turn the armature. Solenoid- Pulls and engage starter pinion gear with the ring gear.

STARTING SYSTEM Question 2. A starter is called an electrical-mechanical device. True or False?

Explain the components of the starter motor. 5.1.4 Explain the components of the starter motor. Components: Starter housing - Holds the armature, brushes, field coils and armature bearings. Armature - turning power Field coils - Create a strong magnetic field to turn the armature. Brushes – Carry current to revolving armature. Commutator - Keep motor turning by controlling the current Solenoid - Pulls and engage starter pinion gear with Pinion gear – engages with the engine ring gear.

STARTING SYSTEM Question 3. What is the purpose of the brushes. Keep the motor running by controlling the current. Carry current to revolving armature. Activate the starter system. Source of electric energy

PERFORM A STARTER CHECK ON A VEHICLE SO 5.2 PERFORM A STARTER CHECK ON A VEHICLE 5.2.1 Do a visual inspection of obvious faults. 5.2.2 Crank starter and measure battery voltage drop. 5.2.3 Measure starting current trough system. 5.2.4 Interpret voltage drop and starter current and draw conclusions.

Do a visual inspection of obvious faults. SO 5.2.1 Do a visual inspection of obvious faults. Check battery voltage Check starter wiring and connections, Check starter mountings and bolts.

STARTING SYSTEM An ammeter measures. Question 4. An ammeter measures. Voltage drop during engine cranking The integrity of the starter wiring The current draw during engine cranking The condition of the brushes

Crank starter and measure battery voltage drop. SO 5.2.2 Crank starter and measure battery voltage drop. Connect multi-meter to battery. Crank starter and measure battery voltage drop

Measure starting current trough system. SO 5.2.3 Measure starting current trough system. Connect an ammeter. Disable engine. Crank engine for 15 seconds and note voltage and current readings.

STARTING SYSTEM Question 5. A starter is called an electrical-mechanical device. True or False?

Interpret voltage drop and starter current and draw conclusions. SO 5.2,4 Interpret voltage drop and starter current and draw conclusions. High current reading Starter motor most probably faulty. Remove starter and inspect.

STARTING SYSTEM Question 6. A starter high current draw test usually indicates: a discharged battery engine problems starter problems high resistance in positive battery cable

PERFORM BASIC MAINTENANCE ON THE MOTOR OF A STARTER. SO 5.3 PERFORM BASIC MAINTENANCE ON THE MOTOR OF A STARTER. ADHERE TO SAFETY PRECEDURES Remove starter from engine. Disassemble starter. Inspect components for serviceability. Replace parts. Assemble starter and test its performance. Refit starter motor.

Remove starter from engine. SO 5.3.1 Remove starter from engine. Remove battery negative cable. Disconnect all wiring from starter motor Unscrew and remove the two starter mounting bolts Remove starter motor from vehicle. Replace a starter

STARTING SYSTEM Question 7 The starter motor is normally situated: Towards the front of the engine? At the rear of the engine close to the flywheel? Bolted to the bell housing? Towards the rear of the engine?

Disassemble starter. SO 5.3.2 NOTE: Mark all parts. Remove solenoid Remove front and rear end plates Remove starter clutch Remove brushes Disassemble a starter

STARTING SYSTEM Question 8. When an engine starts, the pinion gear is disengaged by” Solenoid return spring Solenoid plunger Magnetic switch Over- running clutch

Inspect components for serviceability. SO 5.3.3 Inspect components for serviceability. Check armature: Isolation and ground problems. Inspect field coils: Isolation and ground problems. Inspect solenoid magnetic switch: No binding Inspect and test starter clutch. (Bendix): Inspect tooth wear and slippage. Check brushes: Standard length 16 mm.

SO 5.3.4 Replace parts. Conclusions from inspection will determine serviceability of the different components. Replace components that do not comply with manufacture specifications.

STARTING SYSTEM Question 9. Checking and inspecting the starter components enquire only: Visual checks only Diagnosing the components Testing the components Using a multi-meter for testing continuity

Assemble starter and test its performance. SO 5.3.5 Assemble starter and test its performance. Different starter tests. Pull-in-test Hold-in-test Clutch pinion return test Pinion clearance No load test Test car starter

STARTING SYSTEM Question 10. An open fault in the hold-in winding of a starter solenoid switch will most likely cause: a) the battery to run down. b) the solenoid to move in and out, or chatter. c) the starter drive to remain engaged after the engine is running. d) excessively high current draw from the starter .

SO 5.3.6 Refit starter motor. Refit starter and secure all mounting bolts and nuts. Refit all wiring Refit battery negative cable Start engine and observe starter performance.

STARTING SYSTEM Question 11. Refitting the starter motor after repairs requires: Submit a written report Testing the operation of the starter motor Order new parts

STARTING SYSTEM Any Questions?? THANK YOU