Isuzu N-Series. Manual - part 349

6A3-48 ENGINE (4HF1 / 4HF1-2 / 4HE1-TC / 4HG1 / 4HG1-T)

CAMSHAFT ASSEMBLY 

Component

Removal

Preparation

• Disconnect battery ground cable.
• Tilt the cab.

1. Nozzle Cover
2. Cylinder Head Cover
3. Cylinder Head Cover Gasket
4. Rocker Arm Shaft Assembly

Above works refer to “ROCKER ARM SHAFT AS-
SEMBLY” section in this manual.

5. Valve Cap
6. Camshaft Bearing Cap
7. Camshaft Bearing Upper
8. Camshaft Assembly
9. Camshaft Bearing Lower

Legend

1. Nozzle cover

6. Camshaft bearing cap

2. Cylinder head cover

7. Camshaft bearing upper

3. Cylinder head cover gasket

8. Camshaft assembly

4. Rocker arm shaft assembly

9. Camshaft bearing lower

5. Valve cap

N6A0470E

ENGINE (4HF1 / 4HF1-2 / 4HE1-TC / 4HG1 / 4HG1-T) 6A3-49

• If the camshaft bearings are to be reinstalled,

mark their fitting positions by tagging each
bearing with the cylinder number from which it
was removed.

Installation

1. Camshaft Bearing Lower
2. Camshaft Assembly

1) Turn the crankshaft in the direction of normal

rotation until the timing mark on the crankshaft
damper pulley is aligned with the TDC notched
line.

2) Apply engine oil to the camshaft journal and the

camshaft bearing surfaces before installation.

3) Carefully align the camshaft gear “I” mark and

the cylinder head upper face shown in the illus-
tration.

3. Camshaft Bearing Upper
4. Camshaft Bearing Cap

• Install the bearing caps with the bearing cap

head mark (arrow) facing forward.

• Apply a coat of engine oil to the bearing cap

bolt and stud threads.

• Tighten the bearing cap bolts and studs to the

specified torque.

Tighten:
Camshaft bearing cap nut and bolt to 27 N

⋅m (2.8 kg⋅m/

20 lb

⋅ft)

Legend

1. Camshaft bearing cap
2. Camshaft bearing upper
3. Camshaft assembly 
4. Camshaft bearing lower

N6A0471E

N6A0472E

N6A0109E

6A3-50 ENGINE (4HF1 / 4HF1-2 / 4HE1-TC / 4HG1 / 4HG1-T)

5. Valve Cap

Apply engine oil to the inside of the valve caps and
install them to the valve stem end.

Caution:
Take sufficient care not to let the valve caps fall into the
gear.

6. Rocker Arm Shaft Assembly

Above works refer to “ROCKER ARM SHAFT AS-
SEMBLY” section in this manual.

7. Cylinder Head Cover Gasket
8. Cylinder Head Cover

Above works refer to “CYLINDER HEAD COVER”
section in this manual.

9. Nozzle Cover

• Connect the battery ground cable.
• Lower the cab.
• Start engine and check for oil leakage carefully.

N6A0474E

N6A0475E

ENGINE (4HF1 / 4HF1-2 / 4HE1-TC / 4HG1 / 4HG1-T) 6A3-51

CYLINDER HEAD 

Component

Engine Right Side

Legend

1. Front exhaust pipe

3. A/C compressor (If equipped with A/C)

2. A/C compressor drive belt (If equipped with A/C)

N6A0476E