Isuzu engine 4j series. Manual - part 16

SERVICE INFORMATION 00 – 63

MEMO

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GENERAL ENGINE MECHANICAL 6A – 1

SECTION 6A

GENERAL ENGINE MECHANICAL

CONTENTS

PAGE

Cylinder Head................................................................................................................. 6A -

Valve Spring, Valve Guide Oil Seal, Valve Guide, Push Rod ..................................... 6A - 10

Camshaft, Tappet........................................................................................................... 6A - 17

Rocker Arm Assembly................................................................................................... 6A - 24

Oil Pump ......................................................................................................................... 6A - 27

Crankshaft ...................................................................................................................... 6A - 31

Piston and Connecting Rod.......................................................................................... 6A - 47

Cylinder Block................................................................................................................ 6A - 56

HOME

6A – 2

GENERAL ENGINE MECHANICAL

CYLINDER HEAD

NOTE:
•

During disassembly, be sure that the valve train
components are kept together and identified so
that they can be re-installed in their original
locations.

•

Before removing the cylinder head from the engine
and before disassembling the valve mechanism,
make a compression test and note the results.

DISASSEMBLY

1. Thermostat Housing Assembly

2. Injection Nozzle Holder (4JG2)

2a. Injection Nozzle Holder (4JB1, 4JB1TC)

1) Remove the nozzle holder bracket nuts.

6A-2-1.tif

6A-2-2.tif

(4JB1)

Disassembly steps
1. Thermostat housing Assembly
2. Injection nozzle holder (4JG2)
2a. Injection nozzle holder (4JB1・

4JB1TC)

3. Glow plug and plug connector

(4JG2)

3a. Glow plug and plug connector

(4JB1・4JB1TC)

4. Rocker arm shaft and rocker arm
5. Push rod
6. Cylinder head

Reassembly steps

To reassemble, follow the
disassembly steps in the reverse
order.

GENERAL ENGINE MECHANICAL 6A – 3

2) Use the nozzle holder remover and the sliding

hammer to remove the nozzle holder together with
the holder bracket.
Nozzle Holder

Remover: 5-8840-2034-0

Sliding

Hammer: 5-8840-0019-0

3. Glow Plug and Glow Plug Connector (4JG2)

3a. Glow Plug and Glow Plug Connector (4JB1,

4JB1TC)

4. Rocker Arm Shaft and Rocker Arm

5. Push Rod

6. Cylinder Head

•

Loosen the cylinder head bolts a little at a time in
the numerical order shown in the illustration.

NOTE:

Failure to loosen the cylinder head bolts a little at
a time in numerical order will adversely effect the
cylinder head lower surface

CLEAN

•

Cylinder head bolts

•

Cylinder head
Carefully remove all varnish, soot and carbon to
the bare metal. Do not use a motorized wire brush
on any gasket sealing surface.

INSPECTION AND REPAIR

Make the necessary adjustments, repairs, and part
replacements if excessive wear or damage is discovered
during inspection.
•

Cylinder head gasket and mating surfaces for leaks,
corrosion and blow-by. If the gasket has failed,
determine the cause;
- Improper installation
- Loose or warped cylinder head
- Insufficient torque on head bolts
- Warped case surface

1. Cylinder head bolts for damaged threads or stretching

and damaged heads caused by improper use of tools.

CAUTION:

Suspected bolts must be replaced.
2. Cylinder head for cracks, especially between valve

seats and in the exhaust ports.

3. Cylinder head deck for corrosion, sand particles in

head and porosity.

6A-3-1.tif

6A-3-2.tif

Content .. 14 15 16 17 ..