Isuzu N-Series. Manual - part 580

6A1-8 4JB1/4JB1-TC/4JG2/4JH1-TC - ENGINE

INLET MANIFOLD

Component

Removal

Preparation

• Disconnect battery ground cable.
• Drain coolant.

1. Vacuum Hose
2. Air Intake Duct
3. PCV Hose
4. Injection Pipe

• Release injection pipe clip.
• Loosen the flare nut on the injection pump side.
• Loosen the flare nut on the injection nozzle side,

disconnect and put a side the pipe.

5. Oil Level Gauge Guide Tube

Legend

1. Vacuum hose

5. Oil level gauge guide tube

2. Air intake duct

6. Oil cooler water pipe (Oil Cooler Model)

3. PCV hose

7. Inlet manifold

4. Injection pipe

N6A3230E

N6A3231E

4JB1/4JB1-TC/4JG2/4JH1-TC - ENGINE 6A1-9

• Remove the fixing bolt and remove level gauge

guide tube.

6. Oil Cooler Water Pipe (Oil Cooler Model)

• Remove the water pipe bracket bolt.
• Remove the inlet manifold fixing nut.

7. Inlet Manifold

• Remove the manifold fixing bolt and nut.

Installation

1. Inlet Manifold

• Tighten the fixing bolts and nuts to the specified

torque.

Tighten:

• Bolt & nut to 19 N

⋅m (1.9 kg⋅m / 14 lb⋅ft)

2. Oil Cooler Water Pipe (Oil Cooler Model)

• Install the water pipe and tighten the manifold with

water pipe.

• Tighten the pipe bracket bolt of cylinder head rear

side.

3. Oil Level Gauge Guide Tube

• Install the guide tube and tighten the manifold with

guide tube.

4. Injection Pipe

• Connect the injection pipe and tighten flare nut to

the specified torque.

Tighten:

• Flare nut to 29 N

⋅m (3.0 kg⋅m / 22 lb⋅ft)

• Install the pipe clip to the original position.

5. PCV Hose
6. Air Intake Duct
7. Vacuum Hose

• Connect the battery ground cable.
• Pour coolant.
• Start the engine and check coolant leakage.

N6A3232E

N6A3233E

N6A3781E

6A1-10 4JB1/4JB1-TC/4JG2/4JH1-TC - ENGINE

EXHAUST MANIFOLD

Component

Removal

Preparation

• Disconnect battery ground cable.

1. Vacuum Hose (Exhaust Brake Model)

• Remove the vacuum actuator hose.

2. Front Exhaust Pipe Nut

• Remove the fixing nuts from exhaust manifold side.

3. Front Exhaust Pipe Stay Bolt

4. Heat Protector

Legend

1. Vacuum hose

4. Heat protector

2. Front exhaust pipe nut

5. Exhaust manifold

3. Front exhaust pipe stay bolt

N6A3235E

N6A3236E

4JB1/4JB1-TC/4JG2/4JH1-TC - ENGINE 6A1-11

5. Exhaust Manifold

• Remove the manifold bolt and nut, then remove the

manifold and gasket.

Installation

1. Exhaust Manifold

• Tighten the fixing nuts and bolts to the specified

torque.

Tighten:

• Manifold bolt to 26 N

⋅m (2.7 kg⋅m / 20 lb⋅ft)

2. Heat Protector

• Remove the heat protector and tighten to the spec-

ified torque.

Tighten:

• Heat protector bolt to 19 N

⋅m (1.9 kg⋅m / 14 lb⋅ft)

3. Front Exhaust Pipe Stay Bolt

• Tighten the fixing bolts to the specified torque.

Tighten:

• Stay bolt to 40 N

⋅m (4.1 kg⋅m / 30 lb⋅ft)

4. Front Exhaust Pipe Nut

• Tighten the fixing nuts to the specified torque.

Tighten:

• Without exhaust brake to 69 N

⋅m (7 kg⋅m / 51 lb⋅ft)

• With exhaust brake to 69 N

⋅m (7 kg⋅m / 51 lb⋅ft)

5. Vacuum Hose (Exhaust Brake Model)

• Install the two hose a vacuum actuator.
• Connect battery ground cable.
• Start the engine and check coolant leakage.