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STARTING AND CHARGING SYSTEM 6D3-1
SECTION 6D3
STARTING AND CHARGING SYSTEM
CONTENTS
PAGE
Starting System .............................................................................................................. 6D3- 2
General Description........................................................................................................ 6D3- 2
Service Precaution ......................................................................................................... 6D3- 2
Diagnosis......................................................................................................................... 6D3- 2
Starter .............................................................................................................................. 6D3- 3
Removal ...................................................................................................................... 6D3- 3
Installation .................................................................................................................. 6D3- 3
Disassembled View.................................................................................................... 6D3- 4
Inspection and Repair................................................................................................ 6D3- 5
Characteristic Test ..................................................................................................... 6D3- 6
Charging System ............................................................................................................
6D3- 7
General Description........................................................................................................ 6D3- 7
General On-Vehicle Inspection...................................................................................... 6D3- 8
Generator......................................................................................................................... 6D3- 8
Removal ...................................................................................................................... 6D3- 8
Inspection ................................................................................................................... 6D3- 8
Installation .................................................................................................................. 6D3- 9
Diagnosis......................................................................................................................... 6D3-12
Disassembly ............................................................................................................... 6D3-13
Clean ........................................................................................................................... 6D3-14
Inspection ................................................................................................................... 6D3-14
Reassembly ................................................................................................................ 6D3-18
Inspection ................................................................................................................... 6D3-19
Technical Data ................................................................................................................ 6D3-21
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6D3-2 STARTING AND CHARGING SYSTEM
Starting System
General Description
Cranking Circuit
The cranking system consists of a battery, starter, starter
switch, starter relay, etc. These main components are
connected.
Starter
The cranking system employs a magnetic type reduction
starter in which the motor shaft is also used as a pinion shaft.
When the starter switch is turned on, the contacts of magnetic
switch are closed, and the armature rotates. At the same time,
the plunger is attracted, and the pinion is pushed forward by
the shift lever to mesh with the ring gear.
Then, the ring gear runs to start the engine. When the engine
starts and the starter switch is turned off, the plunger returns,
the pinion is disengaged from the ring gear, and the armature
stops rotation. When the engine speed is higher than the
pinion, the pinion idles, so that the armature is not driven.
Service Precaution
CAUTION:
Always use the correct fastener in the proper location.
When you replace a fastener, use ONLY the exact part
number for that application. ISUZU will call out those
fasteners that require a replacement after removal. ISUZU
will also call out the fasteners that require thread lockers
or thread sealant. UNLESS OTHERWISE SPECIFIED, do
not use supplemental coatings (Paints, greases, or other
corrosion inhibitors) on threaded fasteners or fastener
joint interfaces. Generally, such coatings adversely affect
the fastener torque and the joint clamping force, and may
damage the fastener. When you install fasteners, use the
correct tightening sequence and specifications. Following
these instructions can help you avoid damage to parts
and systems.
Diagnosis
Condition Possible cause Correction
Starter does not run Charging failure Repair charging system
Battery Failure Replace Battery
Terminal connection failure Repair or replace terminal connector
and/or wiring harness
Starter switch failure Repair or replace starter switch
Starter failure Repair or replace starter
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STARTING AND CHARGING SYSTEM 6D3-3
Starter
Removal
1. Remove the battery ground cable.
2. Remove harness connectors (1) and (2).
3. Remove bolts from starter.
Installation
1. Install starter assembly.
2. Install mounting bolts and tighten bolts to specified torque.
Torque: 51 N
m (5.2 kgf
m)
3. Connect harness.
4. Reconnect the battery ground cable.
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6D3-4 STARTING AND CHARGING SYSTEM
Disassembled View
Legend
1 Bolt
2 Magnetic Switch
3 Gear Case
4 Piston
5 Piston Shaft
6 Center Bracket7 Armature
8 Yoke Assembly
9 Brush and Brush Holder
10 Washer
11 Rear Cover
12 Through Bolt
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STARTING AND CHARGING SYSTEM 6D3-5
Inspection and Repair
Repair or replace necessary parts if extreme wear or damage
is found during inspection.
Armature
Check for continuity between commutator and segment.
Replace commutator if there is no continuity (i.e.,
disconnected).
Check for continuity between commutator and shaft.
Also, check for continuity between commutator and armature
core, armature core and shaft. Replace commutator if there is
continuity (i.e., internally grounded).
Brush
Measure the length of brush.
Replace with a new one, if it is below the limit.
Brush Holder
Check for continuity between brush holder (+) (4) and base (-).
Replace, if there is continuity (i.e., insulation is broken).
Magnetic Switch
Check for continuity of shunt coil between terminals S and M.
Replace, if there is no continuity (i.e., coil is disconnected).
Continuity of Series Coil
Check for continuity between terminals S and M.
Replace, if there is no continuity (i.e., coil is disconnected).
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6D3-6 STARTING AND CHARGING SYSTEM
Continuity of Contacts
With the plunger faced downward, push down the magnetic
switch. In this state, check for continuity between terminals B
and M. Replace, if there is no continuity (i.e., contacts are
faulty).
Pinion
Check if the pinion rotates smoothly in drive direction by hand,
or if it is locked when it is rotated in reverse. If not, replace the
pinion.
Characteristic Test
For easily confirming the characteristics, conduct the noload
test as follows:
Rating as short as 30 seconds requires rapid testing.
Fix the starter on the test bench, and wire as shown in
illustration. When the switch is closed, the current flows and
the starter runs under no load. At this time, measure current,
voltage and speed to check if they satisfy the standard.
Legend
1 Volt Meter
2 Revolution Indicator
3 Battery
4 Ammeter
5 Switch
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STARTING AND CHARGING SYSTEM 6D3-7
Charging System
General Description
The charging system is an IC integral regulator charging
system and its main components are connected as shown in
illustration.
The regulator is a solid state type and it is mounted along with
the brush holder assembly inside the generator installed on the
rear end cover.
The generator does not require particular maintenance such as
voltage adjustment. The rectifier connected to the stator coil
has eight diodes to transform AC voltage into DC voltage.
This DC voltage is connected to the output terminal of
generator.
Legend
1 Startor assembly
2 Housing
3 Slipring
4 Screws (2)
5 Regulator
6.Bolt (4)7 Rectifier assem bly
8 Retaining assem bly
9 B+ terminal nut and washer
10 Pulley
11 Rotor assembly
12 Ball bearing
2
11
12
28 54
31
11 7 6 10
9
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6D3-8 STARTING AND CHARGING SYSTEM
General On-Vehicle Inspection
The operating condition of charging system is indicated by the
charge warning lamp. The warning lamp comes on when the
starter switch is turned to "ON" position. The charging system
operates normally if the lamp goes off when the engine starts.
If the warning lamp shows abnormality or if undercharged or
overcharged battery condition is suspected, perform diagnosis
by checking the charging system as follows:
1. Check visually the belt and wiring connector.
2. With the engine stopped, turn the stator switch to "ON"
position and observe the warning lamp.
If lamp does not come on:
Disconnect wiring connector from generator, and ground
the terminal "L" on connector side.
If lamp comes on:
Repair or replace the generator.
Generator
Removal
1. Disconnect battery ground cable.
2. Move drive belt tensioner to loose side using wrench then
remove drive belt.
3. Disconnect terminal "B" wiring connector and connector.
4. Remove generator assembly.
Generator Power and Circuit Diagram
Inspection
Legend
1 Load resistor, set parallel to battery
2 Battery
3 Voltmeter
4 Ammeter
5 Ignition Lock
6 Charge Telltale
7 Generator
1. Disconnect battery.
2. Close off connecting cable from alternator terminal "B+".
3. Set ammeter (measuring range 100A) in disconnected line.
4. Connect controllable load resistor to battery terminal.
5. Set resistor in front of connection to "O"; connect first to
battery, then to resistor.
6. Connect tachometer.
7. Connect oscilloscope according to manufacturer's
instructions.
8. Connect battery.
9. Start engine and read off resulting current at various engine
speeds.