Isuzu 4LE2 Instruction manual

INDUSTRIAL
DIESEL ENGINE
4LE2
MODEL
©2003 ISUZU MOTORS LIMITED
WORKSHOP MANUAL

FOREWORD
This Workshop Manual is designed to help you perform necessary
maintenance, service, and repair procedures on applicable Isuzu
industrial engines.
Information contained in this Workshop Manual is the latest
available at the time of publication.
Isuzu reserves the right to make changes at any time without prior
notice.

TABLE OF CONTENTS
SECTION 1. GENERAL INFORMATION.................................. 1
SECTION 2. ENGINE....................................................... 27
SECTION 3. LUBRICATING SYSTEM.................................... 79
SECTION 4. COOLING SYSTEM ......................................... 83
SECTION 5. FUEL SYSTEM............................................... 89
SECTION 6. TROUBLESHOOTING....................................... 101
SECTION 7. SPECIAL TOOL .............................................. 107
SECTION 8. CONVERSION TABLE....................................... 109

GENERAL INFORMATION 1
SECTION 1
GENERAL INFORMATION
TABLE OF CONTENTS
CONTENTS PAGE
GENERAL REPAIR INSTRUCTIONS ....................................................................... 2
NOTES ON THE FORMAT OF THIS MANUAL ........................................................... 2
APPEARANCE................................................................................................ 5
MAIN DATA AND SPECIFICATIONS....................................................................... 6
TIGHTENING TORQUE SPECIFICATIONS ................................................................ 7
ANGULAR NUT AND BOLT TIGHTENING METHOD.................................................... 9
TIGHTENING TORQUE ON MAJOR COMPONENTS ................................................... 11
GASKET LOCATION......................................................................................... 17
MAINTENANCE.............................................................................................. 20
RECOMMENDED LUBRICATING OIL...................................................................... 25

2GENERAL INFORMATION
GENERAL REPAIR INSTRUCTIONS
1. Before performing any service operation with the engine mounted, disconnect the grounding cable
from the battery.
This will reduce the chance of cable damage and burning due to short circuiting.
2. Always use the proper tool or tools for the job at hand.
Where specified, use the specially designed tool or tools.
3. Use genuine ISUZU parts referring ISUZU PARTS CATALOG for the engines.
4. Never reuse cotter pins, gaskets, O-rings, lock washers, and self locking nuts. Discard them as you
remove them. Replace them with new ones.
5. Always keep disassembled parts neatly in groups. This will ensure a smooth reassembly operation.
It is especially important to keep fastening parts separate. These parts vary in hardness and design,
depending on their installation position.
6. All parts should be carefully cleaned before inspection or reassembly.
Oil ports and other openings should be cleaned with compressed air to make sure that they are com-
pletely free of obstructions.
7. Rotating and sliding part surfaces should be lubricated with oil or grease before reassembly.
8. If necessary, use a sealer on gaskets to prevent leakage.
9. Nut and bolt torque specifications should be carefully followed.
10. Always release the air pressure from any machine-mounted air tank(s) before dismounting the engine
or disconnecting pipes and hoses.
11. Always check and recheck your work. No service operation is complete until you have done this.
12. Information contained in the “Main Data and Specifications” of the Workshop Manual and the Instruc-
tion Book may differ. In this case, the information contained in the Instruction Book should be
considered applicable.
NOTES ON THE FORMAT OF THIS MANUAL
This Workshop Manual is applicable to the 4LE2 family of industrial diesel engines. Unless otherwise
specified, these engines have common parts and components as well as data and specifications.
Illustrations used in this Workshop Manual are based on the 4LE2 engines.
1. Find the applicable section by referring to the Table of Contents at the beginning of the Manual.
2. Common technical data such as general maintenance items, service specifications, and tightening
torques are included in the “General Information” section.
3. Each section is divided into sub-sections dealing with disassembly, inspection and repair, and
reassembly.
4. When the same servicing operation is applicable to several different units, the manual will direct you
to the appropriate page.
5. For the sake of brevity, self-explanatory removal and installation procedures are omitted.
More complex procedures are covered in detail.

GENERAL INFORMATION 3
6. Each service operation section in this Workshop Manual begins with an exploded view of the applica-
ble area.
(Example)
Major components
Figures in parentheses “( )” show the order of disassembling or reassembling.
7. Measurement criteria are defined by the terms “standard” and “limit”.
A measurement falling within the “standard” range indicates that the applicable part or parts are ser-
viceable.
“Limit” should be thought of as an absolute value.
A measurement which is outside the “limit” indicates that the applicable part or parts must be either
repaired or replaced.
8. Components and parts are listed in the singular form throughout the Manual.
Fig. 1
Water Outlet Pipe (5)
Packing (6)
Thermostat (7)
Water pump ASM (8)
Pulley; Fan (4)
Spacer (2)
Belt; Fan (3)
Fan; Cooling (1)

4GENERAL INFORMATION
9. The following symbols appear throughout this Worshop Manual. They tell you the type of service
operation or step to perform.
. . . Remove . . . Adjustment
. . . Installation . . . Cleaning
. . . Disassembly . . . Important Operation Requiring Extra Care
. . . Reassembly . . . Specified Torque (Tighten)
. . . Alignment (Marks) . . .
. . . Directional Indication . . .
. . . Inspection . . . Lubrication (Oil)
. . . Measurement . . . Lubrication (Grease)
. . . Sealant
10. Direction used in this Manual are as follows:
Front
The cooling fan side of the engine viewed from the flywheel.
Right
The injection pump side of the engine.
Left
The exhaust manifold side of the engine.
Rear
The flywheel side of the engine.
Cylinder numbers are counted from the front of the engine.
The front most cylinder is No. 1 and rear most cylinder is No.
The engine’s direction of rotation is counterclockwise viewed from the flywheel.
Special Tool Use Required for Recommended
(Isuzu Tool or Tools)
Commercially Available Tool Use Required or
Recommended

GENERAL INFORMATION 5
APPEARANCE
1. MODEL 4LE2
(1) Left side view
(2) Right side view
Fig. 2
Fig. 3

6GENERAL INFORMATION
MAIN DATA AND SPECIFICATIONS
1. MODEL 4LE2
Item Engine model(s) 4LE2
Type 4-cycle, verlical in-line, water cooled, OHV
Timing drive system Gear drive
No. of cylinders - bore ×stroke mm 4 – 85 ×92
Displacement L (cid) 2.179 (133)
Compression ratio 18.8 : 1
Type of combustion Direct injection
Overall length ×width ×height mm * 691 ×449 ×616
Dry weight kg (lb) * 155 (342)
Fuel injection timing (BTDC) (when at stop) * 14°
Firing order 1 – 3 – 4 – 2
Fuel Highspeed diesel fuel (SAE No.2)
Idling speed min-1 * 850
Compression pressure MPa(kg/cm2/psi) 3 (31/440) or more/250 min-1
Valve clearance (cold) Intake 0.4 (0.0157)
mm (in) Exhaust 0.4 (0.0157)
Intake valve Open (BTDC) 15°
Valve Close (ABDC) 29°
operating
Exhaust valve Open (BBDC) 40°
timing Close (ATDC) 16°
Injection pump Bosch type
Governor Mechanical type
Nozzle Multi-hole type
Injection pressure MPa(kg/cm2/psi) * 17.7 (180/2560)
Oil pump Trochoid type
Oil filter Cartridge type
Lubricant capacity: In total L (qts) * About 8.7 (9.2)
Generator output (V – A) * 12 – 35
Starter output (V – KW) * 12 – 2.0
(Note) These specifications may be subject to change without notice.
Figures in the column with an asterisk (*) are different for each machine. Refer to the specifica-
tions provided by machine manufacturers.

GENERAL INFORMATION 7
TIGHTENING TORQUE SPECIFICATIONS
The tightening torque values given in the table below are applicable to the bolts unless otherwise
specified.
STANDARD BOLT N·m (kgf·m)
An asterisk (*) indicates that the bolts are used for female threaded parts that are made of soft materials
such as casting.
Bolt
Identification
Bolt
Diameter ×
pitch (mm)
M 6 × 1.0
M 8 × 1.25
M10 × 1.25
* M10 × 1.5
M12 × 1.25
* M12 × 1.75
M14 × 1.5
* M14 × 2.0
M16 × 1.5
* M16 × 2.0
M18 × 1.5
* M18 × 2.5
M20 × 1.5
* M20 × 2.5
M22 × 1.5
* M22 × 2.5
M24 × 2.0
* M24 × 3.0
003.9〜007.8 {00.4〜00.8}
007.8〜017.7 {00.8〜01.8}
020.6〜034.3 {02.1〜03.5}
019.6〜033.4 {02.0〜03.4}
049.1〜073.6 {05.0〜07.5}
045.1〜068.7 {04.6〜07.0}
076.5〜115.0 {07.8〜11.7}
071.6〜107.0 {07.3〜10.9}
104.0〜157.0 {10.6〜16.0}
100.0〜149.0 {10.2〜15.2}
151.0〜226.0 {15.4〜23.0}
151.0〜226.0 {15.4〜23.0}
206.0〜310.0 {21.0〜31.6}
190.0〜286.0 {19.4〜29.2}
251.0〜414.0 {25.6〜42.2}
218.0〜328.0 {22.2〜33.4}
359.0〜540.0 {36.6〜55.0}
338.0〜507.0 {34.5〜51.7}
004.9〜009.8 {00.5〜01.0}
011.8〜022.6 {01.2〜02.3}
027.5〜046.1 {02.8〜04.7}
027.5〜045.1 {02.8〜04.6}
060.8〜091.2 {06.2〜09.3}
056.9〜084.4 {05.8〜08.6}
093.2〜139.0 {09.5〜14.2}
088.3〜131.0 {09.0〜13.4}
135.0〜204.0 {13.8〜20.8}
129.0〜194.0 {13.2〜19.8}
195.0〜293.0 {19.9〜29.9}
196.0〜294.0 {20.0〜30.0}
270.0〜405.0
{ 27.5〜41.3}
249.0〜375.0 {25.4〜38.2}
363.0〜544.0 {37.0〜55.5}
338.0〜507.0 {34.5〜51.7}
431.0〜711.0 {43.9〜72.5}
406.0〜608.0 {41.4〜62.0}
016.7〜030.4 {01.7〜03.1}
037.3〜062.8 {03.8〜06.4}
036.3〜059.8 {03.7〜06.1}
075.5〜114.0 {07.7〜11.6}
071.6〜107.0
{ 07.3〜10.9}
114.0〜171.0
{ 11.6〜17.4}
107.0〜160.0
{ 10.9〜16.3}
160.0〜240.0
{ 16.3〜24.5}
153.0〜230.0
{ 15.6〜23.4}
230.0〜345.0
{ 23.4〜35.2}
231.0〜346.0
{ 23.6〜35.3}
317.0〜476.0 {32.3〜48.5}
293.0〜440.0 {29.9〜44.9}
425.0〜637.0 {43.3〜64.9}
394.0〜592.0 {40.2〜60.4}
554.0〜831.0 {56.5〜84.7}
521.0〜782.0 {53.1〜79.7}

TIGHTENING TORQUE SPECIFICATIONS
The tightening torque values given in the table below are applicable to the bolts unless otherwise
specified.
FLANGED HEAD BOLT N·m (kgf·m)
A bolt with an asterisk (*) is used for female screws of soft material such as cast iron.
M 6 × 1.0
M 8 × 1.25
M10 × 1.25
* M10 × 1.5
M12 × 1.25
* M12 × 1.75
M14 × 1.5
* M14 × 2.0
M16 × 1.5
* M16 × 2.0
004.6〜008.5 {00.5〜00.9}
010.5〜0196 {01.1〜02.0}
023.1〜038.5 {02.4〜03.9}
022.3〜037.2 {02.3〜03.8}
054.9〜082.3 {05.6〜08.4}
051.0〜076.5 {05.2〜07.8}
083.0〜125.0 {08.5〜12.7}
077.2〜116.0 {07.9〜11.8}
116.0〜173.0 {11.8〜17.7}
109.0〜164.0 {11.2〜16.7}
006.6〜012.2 {00.6〜01.2}
015.3〜028.4 {01.6〜02.9}
035.4〜058.9 {03.6〜06.1}
034.5〜057.5 {03.5〜05.8}
077.7〜117.0 {07.9〜11.9}
071.4〜107.0 {07.3〜10.9}
115.0〜172.0 {11.7〜17.6}
108.0〜162.0 {11.1〜16.6}
171.0〜257.0 {17.4〜26.2}
163.0〜244.0 {16.6〜24.9}
018.1〜033.6 {02.1〜03.4}
042.3〜070.5 {04.3〜07.2}
040.1〜066.9 {04.1〜06.8}
085.0〜128.0 {08.7〜13.0}
079.5〜119.0 {08.1〜12.2}
123.0〜185.0 {12.6〜18.9}
116.0〜173.0 {11.8〜17.7}
177.0〜265.0 {18.0〜27.1}
169.0〜253.0 {17.2〜25.8}
Bolt
Identification
Bolt
Diameter ×
pitch (mm)
8GENERAL INFORMATION

GENERAL INFORMATION 9
1. Carefully wash the nuts and bolts to remove all oil
and grease.
2. Apply a coat of molybdenum disulfide grease to the
threads and setting faces of the nuts and bolts.
3. Tighten the nuts and bolts to the specified torque
(snug torque) with a torque wrench.
Snug torque
4. Draw a line [A-B] across the center of each bolt.
Center line
ANGULAR NUT AND BOLT TIGHTENING METHOD
Fig. 4
Fig. 5
Fig. 6

Line
ABC D
5. Draw another line [C-D] on the face of each of the
parts to be clamped. This line should be an exten-
sion of the line [A-B].
6. Draw another line [F-G] on the face of each of the
parts to be clamped. This line will be in the direc-
tion of the specified angle [Q] across the center [E]
of the nut or bolt.
Specified angle (Q)
Coinciding line
E
F
G
7. Use a socket wrench to tighten each nut or bolt to
the point where the line [A-B] is aligned with the line
[F-G].
A
B
CD
F
G
Tighten
Example: Specified Angle and Tightening Rotation
A30°1/12 of a turn
B60°1/6 of a turn
C90°1/4 of a turn
D 180°1/2 of a turn
E 360°One full turn
ABCDE
Fig. 7
Fig. 8
Fig. 9
Fig. 10
10 GENERAL INFORMATION

GENERAL INFORMATION 11
TIGHTENING TORQUE ON MAJOR COMPONENTS
1. COOLING FAN AND WATER PUMP N·m (kgf·m/ft. lb)
Fig. 11
19 – 28
(1.9 – 2.9 / 14 – 21)
12 – 18
(1.2 – 1.8 / 9 – 13)
12 – 18
(1.2 – 1.8 / 9 – 13)
19 – 28
(1.9 – 2.9 / 14 – 21)
To cylinder head
19 – 28
(1.9 – 2.9 / 14 – 21)
To cylinder head
19 – 28
(1.9 – 2.9 / 14 – 21)
34 – 46
(3.5 – 4.7 / 25 – 34)
19 – 28
(1.9 – 2.9 / 14 – 21)

2. CYLINDER HEAD AND CYLINDER HEAD COVER N·m (kgf·m/ft. lb)
Fig. 12
12 GENERAL INFORMATION
2 – 4
(0.2 – 0.4 / 1.4 – 2.9)
8 – 12
(0.8 – 1.2 / 6 – 9)
8 – 12
(0.8 – 1.2 / 6 – 9)
8 – 12
(0.8 – 1.2 / 6 – 8)
(Apply sealant.)
83 – 93
(8.5 – 9.5 / 61 – 69)
↓
60˚ – 90˚
(Apply engine oil.)
19 – 28
(1.9 – 2.9 / 14 – 21)
15 – 20
(1.5 – 2.0 / 11 – 14)
0.9 – 1.1
(0.09 – 0.11 / 0.6 – 0.8)
19 – 28
(1.9 – 2.9 / 14 – 21)
25 – 34
(2.5 – 3.5 / 18 – 25)
(Apply Locktite No.262 to this part.)
(Apply engine oil.)

4. CYLINDER BLOCK AND OTHER COMPONENTS (2) N·m (kgf·m/ft. lb)
Fig. 14
14 GENERAL INFORMATION
20 – 25
(2.0 – 2.5 / 15 – 18)
19 – 28
(1.9 – 2.9 / 14 – 21)
8 – 12
(0.8 – 1.2 / 6 – 9)
8 – 12
(0.8 – 1.2 / 5.8 – 8.7)
19 – 28
(1.9 – 2.9 / 14 – 21)
69 – 88
(7.0 – 9.0 / 51 – 65)
21 – 30
(2.1 – 3.1 / 15 – 22)
(Apply engine oil.)
19 – 28
(1.9 – 2.9 / 14 – 21)
Positioning
pin.
()
19 – 28
(1.9 – 2.9 / 14 – 21)
8 – 12
(0.8 – 1.2 / 6 – 9)
10 – 14
(1.0 – 1.4 / 7 – 10)
15 – 25
(1.5 – 2.5 / 11 – 18) 31 – 41
(3.2 – 4.2 / 23 – 30)

GENERAL INFORMATION 15
5. CYLINDER BLOCK AND OTHER COMPONENTS (3) N·m (kgf·m/ft. lb)
Fig. 15
8 – 12
(0.8 – 1.2 / 6 – 9)
12 – 16
(1.2 – 1.6 / 9 – 12)
Rotate 3/4 turn after
contacted with
sealing surface.
()
Apply Locktite
No.262 (2 locations).
()
8 – 12
(0.8 – 1.2 / 6 – 9)
1.5 – 25
(1.5 – 2.5 / 11 – 18)
8 – 12
(0.8 – 1.2 / 6 – 9)
8 – 12
(0.8 – 1.2 / 6 – 9)
19 – 28
(1.9 – 2.9 / 14 – 21)
19 – 28
(1.9 – 2.9 / 14 – 21) 8 – 12
(0.8 – 1.2 / 6 – 9)
41 – 55
(4.2 – 5.6 / 30 – 41)
(With PTO provided)

6. TURBOCHARGER N·m (kgf·m/ft. lb)
16 GENERAL INFORMATION
Fig. 16
19 – 28
(1.9 – 2.9 / 14 – 21)

GENERAL INFORMATION 17
Fig. 17
GASKET LOCATION
1. LOCATIONS WHERE GASKETS ARE USED
Gasket; nozzle holder
Packin; nozzle holder
Packin; joint bolt
Packin; headcover
(※) Sealant should not be
applied.
Packin;
water outlet pipe
Packin;
idle spring set screw
O-ring;
fuel cut lever
Seal; valve
Gasket;
cylinder head
Oil seal;
crankshaft
rear
Gasket;
exhaust
manifold
Gasket;
exhaust silencer
O-ring;
Oil drain plug
O-ring;
Oil strainer
O-ring;
Oil pump
Oil seal;
crankshaft front
O-ring;
angleich cover
O-ring;
control lever
Packin;
governor
cover
Packin;
rear cover
(PTO)
O-ring
Gasket