Isuzu N-Series. Manual - part 409

6D3-4 CHARGING SYSTEM

DIAGNOSIS

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 sus-
pected, perform diagnosis by checking the charging system as follows:

1. Check visually the belt and wiring connector.
2. With the engine in stop status, turn the starter

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.

N6A1034E

CHARGING SYSTEM 6D3-5

ON-VEHICLE SERVICE

Component

Generator

Removal

Preparation

• Disconnector the battery ground cable.
• Tilt the cab.

1. A/C Compressor Drive Belt (If equipped with A/C)
2. A/C Compressor (If equipped with A/C)

• After disconnecting the A/C compressor har-

ness connector, demount the compressor from
the A/C compressor bracket and fasten it with a
wire to an appropriate location together with the
hoses.

3. Vacuum Pump Oil Pipe
4. Vacuum Pump Rubber Hose
5. Vacuum Hose
6. ACG Harness

Disconnect the B terminal cable and harness con-
nector from generator.

7. Fan Belt
8. Generator
9. Adjust Plate

Installation

1. Adjust Plate

Install the adjust plate as shown in the illustration.

Legend

1. A/C compressor drive belt

6. ACG harness

2. A/C compressor

7. Fan belt

3. Vacuum pump oil pipe

8. Generator

4. Vacuum pump rubber hose

9. Adjust plate

5. Vacuum hose

N6A1035E

6D3-6 CHARGING SYSTEM

2. Generator

Notice:
Before tightening the generator, tighten in advance the
fan belt temporarily after its adjustment.

• Insert the lower fixing bolt from the rear side as

shown in the illustration, and tighten it with a nut
on the front side.

3. Fan Belt

Check the drive belt tension.
Depress the drive belt mid-portion with a 98 N (10
kg / 22 lb) force.

Check the drive belt for cranking and other dam-
age.

Fan Belt Adjustment
Fan belt tension is adjusted by moving the generator.

Tighten:
Bolt to

• (1): 40 N

⋅m (4.1 kg⋅m / 30 lb⋅ft)

• (2): 24 N

⋅m (2.4 kg⋅m / 17 lb⋅ft)

• (3): 46 N

⋅m (4.7 kg⋅m / 34 lb⋅ft)

4. ACG Harness
5. Vacuum Hose
6. Vacuum Pump Rubber Hose
7. Vacuum Pump Oil Pipe

Legend

1. Sliding piece
2. Adjust bolt
3. Adjust plate
4. Nut
5. Generator

N6A1036E

N6A0344E

Drive Belt Deflection

mm (in)

New belt

8 — 12 (0.31 — 0.47)

Reuse belt

10 — 14 (0.39 — 0.55)

N6A0037E

N6A0038E

CHARGING SYSTEM 6D3-7

Tighten:
Vacuum pump oil pipe to

• Cylinder body side: 41 N

⋅m (4.2 kg⋅m / 30 lb⋅ft)

• Generator side: 23 N

⋅m (2.3 kg⋅m / 17 lb⋅ft)

8. A/C Compressor (If equipped with A/C)

• Tighten the fixing bolts to the specified torque.

Tighten:
A/C compressor bolt to 48 N

⋅m (4.9 kg⋅m / 35 lb⋅ft)

Notice:
When installing the compressor fixing bolts, tighten first
the 2 bolts on the rear side, and then the remaining 2 on
the front side.

9. A/C Compressor Drive Belt (If equipped with A/C)

• Install the drive belt adjust belt tension by ad-

justing bolt and tighten the locking nut to the
specified torque.

• Depress the drive belt mid-portion with a 98 N

(10 kg / 22 lb) force.

Tighten:
Locking nut to 27 N

⋅m (2.8 kg⋅m / 20 lb⋅ft)

• Connect the negative battery cable.
• Lower the cab.

N6A1040E

N6A1041E

Legend

1. Belt deflection

Drive Belt Deflection

mm (in)

New belt

16 — 20 (0.63 — 0.79)

Reuse belt

18 — 22 (0.71 — 0.87)

N6A1042E