great-wall Wingle 5 (2016) Workshop manual

长城内燃机

GW4D20/GW4D20B 型增压柴油发动机维修手册

MAINTENANCE MANUAL OF GW4D20/GW4D20B

TURBOCHARGED DIESEL ENGINES

保定长城内燃机制造有限公司 编

Edited by Great Wall Baoding Internal Combustion

Engine Manufacturing Company Limited

MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

II

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

GW4D20/GW4D20B 型增压柴油发动机维修手册

WAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

Edited by Great Wall Baoding Internal Combustion Engine Manufacturing Company Limited

*

CAAMS-1098-138/G·438-QC-09~10-580.00

Introduction

This maintenance manual describes the primary technical data, troubleshooting, maintenance,
disassembly and assembly, adjustment, repair and other related information of the GW4D20/GW4D20B
turbocharged diesel engines so as to provide reference for the related maintenance personnel and
repairman.

MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

III

Foreword

The GW4D20/GW4D20B turbocharged diesel engine is 4-cylinder in line, 4-stroke, 16-air valve, double
overhead camshaft (DOHC), turbocharged (VGT, WGT), air intake intercooled vehicle engine, and
adopts advanced technologies such as the electric control high-pressure common-rail system, electric
control EGR system, etc; it features good power performance, high economical efficiency, high reliability,
excellent performance at both high and low speeds, quick low-temperature startup, etc., and its emission
conforms to China IV Vehicle Exhaust Emission Standard.

The GW4D20/GW4D20B diesel engine is mainly carried various kinds of LCV, SUV/MPV, compact cars,
high-grade pickups produced by Great Wall Motor Company Limited and similar models from other auto
manufacturers.

AS a kind of power machinery reaching the modern advanced level, the GW4D20/GW4D20B
turbocharged diesel engine has complicated structures, and has strict requirements for the material,
technology and cooperation between parts, and correspondingly requires high levels of application,
maintenance and repair.

Maintenance Manual of GW4D20/GW4D20B Turbocharged Diesel Engines is a comprehensive manual
for engine maintenance; it consists of the primary technical data, disassembly and assembly, adjustment,
examination and troubleshooting, etc of the GW4D20/GW4D20B turbocharged diesel engine; you
should carefully read and strictly follow the regulations in the manual and master malfunction diagnosis,
elimination and maintenance of the diesel engine so as to ensure the best working condition of the
engine after maintenance and make the engine reach the desirable power performance and economical
index.

As for the vehicle and mechanical chassis parts concerned in maintenance, repair and troubleshooting
of the diesel engine or the parts supplied by auto and machinery manufacturers, please refer to the
maintenance manual of the vehicle or machinery carrying the engine.

For your life and property security, please use and operate the engine in strict accordance with the safety
information described in this manual. The instructions to important issues should be complied strictly,
otherwise it may cause serious injury or machine, vehicle damage and even danger. The warning in this
manual refers to possible personal danger; caution refers to possible damage to the diesel engine and
attention is used for important information without danger.

Please note that the GW4D20/GW4D20B turbocharged diesel engine will be continuously improved
according to market demands and changes, and information on maintenance and repair of improved
parts will be amended or supplemented when the manual is reprinted.

Contents and technical information from this manual are effective as long as the printing is approved. But
the Great Wall Baoding Internal Combustion Engine Manufacturing Company Limited (called our
company for short thereafter) reserves the right to suspend using and change technical information and
the design at any time without previous notice, and the right to change the supply scope, equipment and
technology. Therefore, users cannot have any claim on the basis of the data, illustrations and
explanations described in this manual. Changes in the range of the product structure, equipment and
technology will not be noticed to users, and our company will not assume any relevant responsibility or
obligation.

We hope to get feedbacks concerning advices on the qualities, performances and structures,
experiences in operation, maintenance and repair of GW4D20/GW4D20B turbocharged diesel engines
from users and readers so as to help us improve our products and technologies of operation,
maintenance and repair. Please send your letter to: Sales and Services Department, Great Wall Baoding
Internal Combustion Engine Manufacturing Company Limited, Dingxing County Development Zone,
Hebei Province, China, Postal Code: 072650.

MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

IV

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

Since this manual covers wide information and is edited in short time, careless omission and even errors
may be detected, and we would greatly appreciate being informed of them. This manual only provides
reference for users in work, and we will not be responsible for any loss or damage caused by using this
manual.

Our company has its authorized repair stations in various regions, users can get consultation and
after-sale service from the nearest authorized repair station on issues concerning use, technical
maintenance, troubleshooting, repair or parts replacement of the diesel engine.

This maintenance manual should not be reprinted or published without the permission from our company.
Our company reserves all copyrights that described in law, and reserves the rights of modification and
explanation.

Great Wall Baoding Internal Combustion Engine Manufacturing Company Limited

Dec. 18, 2009

Table of Contents

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

V

Table of Contents

Chapter I Introduction .............................................................................................................................. 1

Section I How to Use This Manual ............................................................................................................. 1

Section II Main Contents of Civilized Production for Maintenance ............................................................ 4

Section III Fire Control Measures for Maintenance Workshop .................................................................. 4

Section IV Dress Security Requirements for Maintenance Personnel ...................................................... 5

Section V Main Contents of Maintenance Process Regulation ................................................................. 5

Section VI Identification Marks ................................................................................................................... 5

Section VII General Repair Instructions ..................................................................................................... 6

Section VIII Precautions for Maintenance Operation ................................................................................. 8

Chapter II Technical Information of Engine ........................................................................................... 9

Section I Structure of Engine ...................................................................................................................... 9

1. Cylinder head and cylinder body ................................................................................................. 9

2. Crank and Connecting Rod Mechanism ...................................................................................... 9

3. Valve Actuating Mechanism and Intake/Exhaust System ........................................................... 9

4. Turbocharging System ............................................................................................................... 10

5. Fuel Supply System ................................................................................................................... 10

6. Lubrication System ..................................................................................................................... 11

7. Cooling System ........................................................................................................................... 11

8. Startup Device ............................................................................................................................. 11

Section II View of Engine ......................................................................................................................... 12

1. Front View of Engine ................................................................................................................. 12

2. Rear View of Engine .................................................................................................................. 13

3. Left View of Engine .................................................................................................................... 14

4. Right View of Engine ................................................................................................................. 15

5. Vertical View of Engine .............................................................................................................. 16

Section III Main Performance Indexes of Engine ..................................................................................... 17

1. Power Performance Index ......................................................................................................... 17

2. Economical Efficiency Index ...................................................................................................... 17

3. Reliability and Durability Index .................................................................................................. 18

4. Low Public Hazard Index ........................................................................................................... 18

Section IV Engine Property Curves.......................................................................................................... 19

Section V Technical Data and Specifications of Engine ........................................................................... 21

1. Technical Parameters of Engine ................................................................................................ 21

MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

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Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

2. Various Temperature and Pressure Ranges of Engine ............................................................. 23

3. Specifications of Main Engine Accessories ............................................................................... 24

4. Specifications of Main Parts of Fuel Supply System ................................................................. 25

Section VI Maintenance Standard for Engine .......................................................................................... 26

1. Tightening Torque of Main Fasteners of Engine ........................................................................ 26

2. Fit Clearance of Main Parts of Engine ....................................................................................... 28

Section VII Running-in of Engine ............................................................................................................. 32

1. Preparation Before Running-in .................................................................................................. 32

2. Running-in .................................................................................................................................. 32

3. Precautions for Running-in ........................................................................................................ 33

4. Technical Maintenance After Running-in ................................................................................... 33

5. Precautions for Usage of New Vehicles .................................................................................... 33

Section VIII Technical Maintenance for Engine ........................................................................................ 34

1. Technical Maintenance Cycle .................................................................................................... 34

2. Technical Maintenance Contents ............................................................................................... 37

3. Technical Maintenance for Air cleaner ....................................................................................... 40

4. Technical Maintenance for Oil Supply System .......................................................................... 41

5. Technical Maintenance for Fuel Lubrication System ................................................................. 43

6. Technical Maintenance for Cooling System .............................................................................. 46

7. Additional Maintenance in Severe Driving Conditions .............................................................. 48

8. Technical Maintenance During Storage ..................................................................................... 48

9. Precautions in Technical Maintenance ...................................................................................... 48

Section IX Repair Process for Diesel Engine ........................................................................................... 48

1. Repair Process for Diesel Engine .............................................................................................. 48

2. Engine Handover and Repair Class Identification ..................................................................... 49

3. Exterior Washing for the Engine ................................................................................................ 50

Section X Technical Requirements for Engine Removal and Reinstallation ........................................... 51

1. General Technical Requirements for Assembling ...................................................................... 51

2. General Technical Requirements for Removal .......................................................................... 53

Section XI Special Tools and Instruments for Repair ............................................................................... 54

Section XII Repair Operation for Engine .................................................................................................. 56

1. Model Mark ................................................................................................................................ 56

2. Air Cleaner ................................................................................................................................. 56

3. Lubrication System .................................................................................................................... 57

4. Fuel System ............................................................................................................................... 58

5. Cooling System .......................................................................................................................... 59

6. Engine Control ........................................................................................................................... 61

Table of Contents

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

VII

7. Quick start-up system ................................................................................................................ 62

Section XIII Engine Parts and Tightening Torques................................................................................... 63

1. Engine Bracket Mounting Assembly .......................................................................................... 63

2. Cylinder Body Mounting Assembly ............................................................................................ 64

3. Cylinder Body Component ......................................................................................................... 65

4. Cylinder Head Mounting Assembly ——1 ................................................................................. 66

5. Cylinder Head Mounting Assembly ——2 ................................................................................. 67

6. Cylinder Head Mounting Assembly ——3 ................................................................................. 68

7. Piston Connecting Rod Mounting Assembly ............................................................................. 69

8. Crankshaft Flywheel and Clutch Mounting Assembly ............................................................... 70

9. Air Intake and Exhaust Systems Mounting Assembly ——1 ..................................................... 71

10. Air Intake and Exhaust Systems Mounting Assembly ——2 ..................................................... 72

11. Oil Pan and Engine Oil Collector Mounting Assembly .............................................................. 73

12. Engine Oil Pump Mounting Assembly ....................................................................................... 74

13. Engine Oil Cooler and Cooling Pipelines Mounting Assembly .................................................. 75

14. Timing Mechanism Mounting Assembly ——1 .......................................................................... 76

15. Timing Mechanism Mounting Assembly ——2 .......................................................................... 77

16. Fuel Supply System Mounting Assembly ——1① .................................................................... 78

17. Fuel Supply System Mounting Assembly ——2① .................................................................... 79

18. Fuel Supply System Mounting Assembly ——3① .................................................................... 80

19. Turbocharger Mounting Assembly ——1① ............................................................................... 81

20. Turbocharger Mounting Assembly ——2① ............................................................................... 82

21. EGR System Mounting Assembly .............................................................................................. 83

22. Electronic Control System Sensor ............................................................................................. 84

23. Generator Mounting Assembly .................................................................................................. 85

24. Throttle Mounting Assembly ...................................................................................................... 86

25. Thermostat and Water Pump Mounting Assembly .................................................................... 87

26. Engine and Compressor Mounting Assembly ........................................................................... 88

27. Vacuum Pump and Steering Pump Mounting Assembly ........................................................... 89

Chapter III Malfunction Diagnosis and Troubleshooting ................................................................... 90

Section I Troubleshooting ......................................................................................................................... 90

1. Failure to Start the Diesel Engine .............................................................................................. 91

2. Difficulty in Starting the Diesel Engine at a Low Temperature ................................................... 91

3. Insufficient Power in the Diesel Engine ..................................................................................... 92

4. Excessive Fuel Consumption of Diesel Engine ......................................................................... 93

5. Abnormal Noise During the Diesel Engine Running ................................................................. 93

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Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

6. Abnormal Noise from Diesel Engine.......................................................................................... 95

7. Abnormal Smoke from Diesel Engine........................................................................................ 95

8. Heavy Oil Consumption and Low pressure of the Diesel Engine Lubrication System ............. 96

9. Abnormal Coolant Temperature, Lack of Coolant in the Diesel Engine Cooling System ......... 98

10. Malfunction of the Diesel Engine Turbocharging System ......................................................... 99

11. Malfunction of the Diesel Engine Oil Supply System .............................................................. 100

12. Diesel Engine Wobble During Idling ........................................................................................ 103

13. Diesel Engine Running at a High Idle Speed .......................................................................... 104

14. Starter not Working, Lacking Power, and Making noise .......................................................... 104

15. Working Starter but Non-working Diesel Engine ..................................................................... 105

16. Diesel Engine Rotating but Unable to be Started .................................................................... 106

17. Difficulty in Starting Due to Malfunction in the Quick Start-up System .................................... 107

18. No Power Generation, Undercharge or Overhigh Charging Current of Generator ................. 108

19. Insufficient Capacity, Difficulty in Starting or Overhigh Self Discharge of the Storage Battery 109

Section II Malfunction Diagnosis ............................................................................................................ 110

1. Start-up system malfunction diagnosis ..................................................................................... 110

2. Turbocharging System Malfunction Diagnosis ......................................................................... 114

Chapter IV Mechanical System ........................................................................................................... 119

Section I Cylinder Head .......................................................................................................................... 119

Section II Camshaft ................................................................................................................................ 137

Section III Valve, Valve Spring, Valve Oil Seal, Rocker Arm and Hydraulic Clearance Adjuster ........... 148

Section IV Crankshaft ............................................................................................................................. 157

Section V Piston and connecting rod assembly ..................................................................................... 178

Section VI Engine oil pump assembly .................................................................................................... 196

Section VII Cylinder body assembly ...................................................................................................... 201

Chapter V GW4D20 / GW4D20B Turbocharged Diesel Engine........................................................ 215

Section I General .................................................................................................................................... 215

Section II Engine Assembly .................................................................................................................... 216

Section III Engine Brackets .................................................................................................................... 225

Section IV Air Intake Manifold Pipe ........................................................................................................ 235

Section V Exhaust Manifold Pipe ........................................................................................................... 240

Section VI Cylinder Cover ...................................................................................................................... 246

Section VII Camshaft .............................................................................................................................. 253

Section VIII Rocker Arms and Hydraulic Clearance Adjusters .............................................................. 263

Section IX Valve Oil Seal and Valve Spring ........................................................................................... 273

Section X Cylinder Head Assembly and Cylinder Head Gasket ............................................................ 286

Section XI Timing Pulley......................................................................................................................... 298

Table of Contents

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

IX

Section XII Oil Filter and Oil Cooler ....................................................................................................... 303

Section XIII Primary shaft front bearing of the flywheel and transmission ............................................ 306

Section XIV Oil pump assembly ............................................................................................................. 310

Section XV Oil pan assembly ................................................................................................................. 318

Section XVI Piston and connecting rod assembly ................................................................................. 323

Section XVII Front oil seal of crankshaft ................................................................................................ 337

Section XVIII Rear Oil Seal of Crankshaft ............................................................................................. 342

Section XIX Crankshaft .......................................................................................................................... 346

Section XX Cylinder Body Assembly...................................................................................................... 364

Chapter VI Fuel System ....................................................................................................................... 384

Section I General .................................................................................................................................... 384

1. Components of Fuel Supply System ....................................................................................... 384

2. Components of High Pressure Common Rail System ............................................................ 386

Section II On-Board Maintenance .......................................................................................................... 400

1. Fuel Filter Assembly ................................................................................................................ 400

2. Fuel Injector Assembly ............................................................................................................. 403

3. High-Pressure Fuel Pump Assembly ....................................................................................... 407

Chapter VII Cooling System ................................................................................................................ 411

Section I General .................................................................................................................................... 411

1. Water pump ............................................................................................................................... 411

2. Thermostat ............................................................................................................................... 412

3. Radiator ................................................................................................................................... 412

4. Antifreeze fluid ......................................................................................................................... 412

Section II On-Board Maintenance .......................................................................................................... 414

1. Water Pump Assembly............................................................................................................. 414

2. Thermostat ............................................................................................................................... 420

3. Radiator ................................................................................................................................... 424

Chapter VIII Lubrication System ......................................................................................................... 428

Section I General .................................................................................................................................... 428

Section II On-board Repair..................................................................................................................... 429

1. Oil Filter .................................................................................................................................... 429

2. Engine Oil Pump ...................................................................................................................... 432

3. Oil Collector ............................................................................................................................. 439

4. Oil Pan ..................................................................................................................................... 442

Chapter IX Turbocharging System ..................................................................................................... 446

Section I General .................................................................................................................................... 446

1. Turbocharging system composition ......................................................................................... 446

MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

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Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

2. Turbocharger structure ............................................................................................................ 446

Section II On-board Maintenance .......................................................................................................... 449

Section III Inspection and Repair ........................................................................................................... 454

1. Checking the working condition of the exhaust outlet ............................................................. 454

2. Checking the working condition of the turbocharger ............................................................... 455

3. Checking the axial clearance of the impeller shaft. ................................................................. 455

4. Checking the axial clearance of the rotor ................................................................................ 455

5. Checking the clearance between the impeller shaft and the bearing ..................................... 456

6. Checking the radial clearance of the rotor ............................................................................... 456

Chapter X Electronic Control EGR System ....................................................................................... 457

Section I General .................................................................................................................................... 457

Section II On-board Maintenance .......................................................................................................... 458

Chapter XI Electrical System .............................................................................................................. 462

Section I Storage Battery ....................................................................................................................... 462

1. Storage Battery Performance Parameters .............................................................................. 462

2. Preparing Electrolyte ............................................................................................................... 463

3. Charging the Storage Battery .................................................................................................. 464

4. Checking the Storage Battery Remaining Capacity ................................................................ 466

Section II Starting System ...................................................................................................................... 468

1. General .................................................................................................................................... 468

2. On-board Maintenance ............................................................................................................ 470

Section III Charging System ................................................................................................................... 473

1. Generator ................................................................................................................................. 473

2. Diagnosis ................................................................................................................................. 475

3. On-board Maintenance ............................................................................................................ 477

Chapter XII Exhaust System ............................................................................................................... 481

Section I General .................................................................................................................................... 481

Section II On-board Maintenance .......................................................................................................... 481

Section III Front Exhaust Pipe ................................................................................................................ 482

Appendix ............................................................................................................................................... 486

Appendix I Engine Malfunction Code ..................................................................................................... 486

Appendix II Conversion Table of Common Measurement Units for Engines ......................................... 499

Chapter I Introduction

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

1

Cylinder body

Outer rotor

Front oil seal
assembly of
crankshaft

Removing sequence

① Oil pump
② Rubber seal ring
③ Outer rotor

Assembly sequence
Assembly in the sequence reverse to
disassembly.

Oil pump mounting
assembly

Rubber seal
ring

Chapter I Introduction

Section I How to Use This Manual

1. Index

The content (index) of this manual will guide you to the item to be repaired. For the convenience of
finding information, the title of each chapter is given at the header of the singular page.

2. Preparations

Preparations list the special service tools, special service materials, sealant and lubricating oil that
should be prepared before operation and their functions.

3. Repair Procedures

Most repair processes begin with an overview illustration which identifies all parts and how they are
disassembled and assembled (refitted) in sequence. For example, see Fig. 1-1-1 for the disassembly /
assembly schematic diagram for the oil pump parts.

Fig. 1-1-1 Disassembly / Assembly Schematic Diagram for Oil Pump Parts

The repair procedure is introduced in the following sequence:

MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

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Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

Schematic diagram

What to do and where to do it

Title of work task: the content of repair

Mounting the clutch assembly

Using special service tools to mount the clutch
assembly.

Front bearing installer: 5-8522-0024-0

Tool No.

Detailed explanation: how

to carry out the work.

Torque: 23 N·m ± 3 N·m Specification

Check the assembly quality.

Fig. 1-1-2 Mounting the Clutch Assembly

(1) The schematic diagram shows what to do and where to do it, see Fig. 1-1-2.
(2) The title of the work task shows the content of repair.
(3) Explain in detail how to carry out the work content and provide other technical information, such as

specification and attention, note, etc., and the quantity and dimensions of fasteners.
For example:

This form provides a shortcut for the experienced technical personnel to obtain the data required. The
work task title on the top makes the content of repair clear at a glance, while the content below it
provides the detailed explanation. Important specification, attention, warning and caution always stand
out in ―boldface‖.

4. References

To improve lookup and work efficiency, this manual adopts references as few as possible; however, the
Section No. and Page No. are given when necessary.

5. Specifications

Specifications are listed separately when necessary. There is no need to leave your work for looking up
specifications. The specifications are listed at the end of every section for quick reference.

6. Warning, Attention, Caution, Prompt:

―Warning!‖ is shown in ―boldface‖ to remind the possibility of personnel injury to you or others.

―Attention!‖ is shown in ―boldface‖ to remind the possibility of damage to parts being repaired..

―Caution!‖ is shown with ―boldface‖ to remind the possibility of damage to diesel engine.

Chapter I Introduction

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

3

―Prompt‖ is separated from the text and is shown in ―boldface‖; it provides additional information to

help you carry out the repair more effectively.

7. Marks

Disassembling: separate the integrity (the whole engine) into constituent parts.

Removing: separate the engine (the components) and detach the parts.

Assemble (refitting, assembling): assembling parts or components into the integrity (the whole

engine).

Mounting: fix parts at the specified positions (of the engine) according to certain technical

requirements.

Checking, testing: make careful checking, examination and determination in order to find (the

engine) problems (or malfunctions).

Washing, cleaning: clean up; without dust, oil stain, etc.

Tightening, fastening: make an object rotate to fix or secure it; the object is fixed or secured by

outer force.

Remind the need to use special tools while performing disassembling or assembling.

Remind the need to apply engine oil for lubrication (see Table 2-6-7 for lubrication positions before

assembling the engine).

Remind the need to apply sealant (see Table 2-6-8 for sealant-applied positions while assembling

the engine).

8. Measurement Units

The measurement units adopted in this manual are mainly SI units (the standard international unit).
For example:
Torque: N·m;
Force: N;
Power: W, kW;
Length: μm, mm, m, km;
Rotating speed: r/min;
Pressure, pressure strength: Pa, kPa, MPa;
Temperature: °C
Volume: mL, L;
Mass: g, kg;
Electric current: A;
Electric resistance: Ω, kΩ;

MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

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Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

Voltage: V;
Plane angle: °;
Noise: dB/A;
Time: s, min, h.

Section II Main Contents of Civilized Production for Maintenance

Civilized production is aimed at creating a good producing condition and working environment to
improve maintenance quality, ensure personnel and device security, and improve labor efficiency. The
main contents are as follows:

(1) Design and decorate the workshop according to requirements for maintenance and labor protection,
such as ventilation, lighting, fire control, noise control, etc.

(2) Keep the workshop and work place clean.
(3) Equipping special maintenance and examination tools and avoiding forced disassembly and

assembly.
(4) Store the components and parts of the engine assembly at the specified rack in the specified

storeroom in order, and prevent fire and theft.
(5) Keeping all kinds of maintenance facilities, tools, fixtures, and measuring instruments in good

condition.
(6) Proving mature maintenance process regulations, technical documents and standards, and

performing work according to the procedures and specifications.
(7) Keep maintenance records, and comply with the handover procedures. The repair records contain:

① Main problems (serious wear or accidental damage) detected after the engine is disassembled; ②
Records and conclusions of technical appraisal for major parts; ③ Registration of replacing with new
pieces and repaired pieces; ④ Results of quality tests during and after repair; ⑤ Records of test data.
Vehicle takeover records contain the following filled items: ① Who and when to send the vehicle for
repair; ② Last repair and replacement conditions; ③ The working condition of vehicle after the last repair;
④ The maintenance condition of the engine, and malfunctions that ever happened; ⑤ The damage
condition of the engine and the name of the exterior missing parts; ⑥ The item to be repaired and the
deadline required by the sender and agreements concerning fee.

(8) The maintenance personnel should keep clean and tidy appearances, behave in good manner, work
in solidarity and cooperation, observe disciplines and service with enthusiasm.

Section III Fire Control Measures for Maintenance Workshop

(1) Flammable materials such as vehicles, diesel, ethyl alcohol, oil paint and refrigerant should be kept
away from fire and heat sources.

(2) Used cleaning cloth, waste cotton fabric, oil stained gloves, packaging cartons of parts and plastic
packaging bags should be collected and placed in the safe place or metallic container.

(3) No smoking, no eating in the workshop.
(4) The workshop should be equipped with fire fighting equipment and tools, and special persons should

be assigned to manage them. Fire control education should be implemented regularly, and a fire control
supervisor should be specified.

Chapter I Introduction

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

5

Section VI Identification Marks

Serial number of the engine
The serial number of GW4D20/GW4D20B turbocharged diesel

engine is stamped on the left cylinder body, as shown in Fig.
1-6-1.

Fig. 1-6-1 Serial Number

Identification of Diesel Engine

Position of

identification mark

Machine code

Asterisk

Year

Month

Serial number

Asterisk

Section IV Dress Security Requirements for Maintenance Personnel

(1) The maintenance personnel should wear work wear during working.
(2) The personnel with long hair or a long braid should wear a working hat, and the braid should be

wrapped into the hat to prevent from being involved into the rotating machine.
(3) Do not open your clothes or loosen the cuff when carrying out repair; do not wear gloves when

operating the rotating machine.
(4) When there are strong light, or metal debris splashing in the work area, and when working on the

place in contact with strong acid, refrigerant and other chemicals, wear safety goggles.

Section V Main Contents of Maintenance Process Regulation

The contents of the maintenance process regulation for the engine are as follows:
(1) The procedure sequence and detailed operation contents to accomplish the maintenance work.
(2) The tools, equipment and correct operating methods that should be adopted to ensure the

maintenance quality and operation security.
(3) Quality test items and test facilities that should be used during maintenance.
(4) Quality requirements that should be met in the process of maintenance.
(5) Norm of the working hour to accomplish the maintenance work.

MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

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Great Wall Baoding Internal Combustion Engine
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Fig. 1-7-1 Removing the Negative (-) Cable of

Battery

Fig. 1-7-2 Precoating Sealant on Parts

Fig. 1-7-3 Torque Spanner

1. When carrying out repair, use the baffle, seat and
floor mat to keep the vehicle clean and intact and
prevent damage.

2. During disassembly, keep parts in a proper order so
as to facilitate reassembly.

3. The rules that should be observed during repair.

3.1 Before performing electrical repair, disconnect the
negative (-) cable from the storage battery, as shown in
Fig. 1-7-1.

3.2 If it is necessary to disconnect the storage battery
during check and repair, the negative (-) cable of the
storage battery should be disconnected first, as it
connects to the vehicle body and constitutes the earth
wire.

3.3 To prevent damage to the battery terminal, loosen
the fixed nut of the cable connection terminal and raise
the cable connection terminal without twisting or prying
it.

3.4 Clean the battery terminal and the cable connection
terminal with special cleaning cloth; do not scrape them
with a file or other abrasive objects.

3.5 Unscrew the nut when connecting the cable terminal
to the battery terminal, and screw it after installation. Do
not use a hammer to tap the cable terminal onto the
battery terminal.

3.6 Be sure to properly cover the positive pole (+) of the
storage battery.

4. Check the hose and conductor connector to ensure
secure and correct connections.

5. Non-reusable parts: as for splint pins, gaskets, O
rings, oil seals, etc., replace them with new parts.

6. Precoated parts: refer to parts that are coated with
sealant in the factory, bolts and nuts, etc., as shown in
Fig. 1-7-2.See Fig. 2-6-8 for positions to coat sealant on
engine parts,.

6.1 If a precoated part is re-tightened, loose or loosened
in any way, it must be recoated with the specified
sealant.

6.2 When reusing a precoated part, clear the old sealant
away from the part surface or the threaded hole, and
clean the surface or the hole with compressed air. Then
apply the specified sealant to the specified position, as
shown in Fig. 1-7-2.

Sealant

Indicating torque spanner

Scale indication torque spanner

Section VII General Repair Instructions

Chapter I Introduction

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

7

Fig. 1-7-4 Jack

Fig. 1-7-5 Pull Apart Fuel Return Hose and

Vacuum Hose

Fig. 1-7-6 Checking the Conductor Connector

7. When necessary, apply sealant to gaskets to prevent
leakage.

8. Strictly observe all specifications for bolt tightening
torques (see Table 2-6-1, 2-6-2), and use the torque
spanner according to technical requirements, as shown
in Fig. 1-7-3.

9. Special repair tools, instruments (see Table 2-11-1)
and special repair materials (see Table 2-6-8, 2-6-9)
may be used, depending on the repair. Be sure to use
special repair tools and special repair materials as
required according to situations, and strictly observe
correct operation specifications. A list of special repair
tools and special repair materials can be found in
"Chapter II Technical Information of Engine‖ in this
manual.

10. Be sure to take care when jacking up and
supporting the vehicle. Be sure to lift and support the
vehicle at the proper locations.

10.1 If the vehicle is to be jacked up only at the front or
rear end, be sure to block the wheels at the opposite
end in order to ensure safety.

10.2 Be sure to hold the vehicle with a support after it is
jacked up. It is extremely dangerous to do any work on
a vehicle raised on a jack alone, even for a small job
that can be finished quickly.

11. Observe the following precautions to prevent
damage to parts:

11.1 Non-specialized personnel should not open the
cover or housing of the electric control unit (ECU).

11.2 When disconnecting the fuel return hose
component and the vacuum hose of the fuel injector,
hold the end but not the middle of the hose, as shown in
Fig. 1-7-5.

11.3 To pull apart the circuit connectors, pull the
connector itself but not the wires, as shown in Fig.
1-7-6.

11.4 Be careful not to drop precision parts, EFI system
elements (such as the oil injector, sensor, ECU, etc.) off,
as shown in Fig. 1-7-7.If they are dropped, they should
be replaced with new parts.

11.5 Never use an impact spanner to disassemble or
mount a temperature sensor or other sensors which has
specific torque requirements.

Hydraulic jack

Scissor jack

Incorrect

Correct

Incorrect

Correct

Correct

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Fig. 1-7-7 Electric Control System Elements

of Engine

Section VIII Precautions for

Maintenance Operation

If the vehicle is equipped with the mobile
communication system, such as the two-way wireless
communication equipment and cellular phone, the
following precautions should be observed:

(1) Install the communication antenna away from the
ECU and sensors of automotive electronic system as
far as possible.

(2) The antenna feeder should be installed more than
20 cm away from the ECU and sensors of automotive
electronic system. For the positions of the ECU and
sensors, please refer to the related sections.

Chapter II Technical Information of Engine

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Manufacturing Company Limited

9

Fig. 2-1-1 Cylinder Head and Cylinder Body

Fig. 2-1-2 Crank and Connecting Rod

Mechanism

Fig. 2-1-3 Valve Actuating Mechanism

Section I Structure of Engine

The diesel engine is a kind of complex machinery that
transforms the thermal energy of fuel into mechanical
power. Although there are various types of diesel engine
with different structures, they all contain the following
mechanisms and systems:

1. Cylinder head and cylinder body

For cylinder head and cylinder body, see Fig. 2-1-1.
The function of the cylinder head is to seal the upper

part of the cylinder and make the upper part of the
cylinder and piston crown constitute the combustion
chamber. The cylinder head is mounted with the intake
valve, exhaust valve, rocker arm, hydraulic lash
adjuster, intake/exhaust camshaft assembly, oil injector,
etc., and is laid with intake and exhaust pipelines, and
cooling water jackets. The cylinder body constitutes the
cylinder and is used to mount and support all
mechanisms and systems of the diesel engine; it is the
foundation and framework of the diesel engine.

2. Crank and Connecting Rod Mechanism

For the crank and connecting rod mechanism of engine,
see Fig. 2-1-2.

The crank and connecting rod mechanism can
accomplish the interconversion between the linear
reciprocating motion of piston (in cylinder) and the
rotation motion of crankshaft, and thereby output the
propulsion produced by gas combustion through the
crankshaft as the output power, and ensure the
fulfillment of working cycles of the diesel engine. The
crank and connecting rod mechanism mainly consists of
the piston, connecting rod, crankshaft, flywheel, etc.

3. Valve Actuating Mechanism and
Intake/Exhaust System

The valve actuating mechanism, intake and exhaust
systems are as shown in Fig. 2-1-3, 2-1-4.

The functions of the valve actuating mechanism and
intake and exhaust systems are opening and closing the
intake valve and exhaust valve in time to ensure the
cylinder to intake flesh and clean air as much as
possible and discharge exhaust gas as clear as
possible timely. It mainly consists of the valve
components (the intake and exhaust valve, valve
pin/clip, valve spring, spring seat, valve oil seal, etc.),
transmission mechanism (the belt, pulley,
intake/exhaust camshaft assembly, rocker arm,

Cylinder

Cylinder body

Connecting
rod

Crankshaft

Connecting
rod cap

Camshaft
assembly

Intake/exhaust
valve component

Chapter II Technical Information of Engine

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Fig. 2-1-4 Intake/Exhaust System

hydraulic lash adjuster, etc.), air filter, intake/exhaust
pipelines, intake/exhaust manifolds, etc. The electric
control EGR valve and EGR cooler contained in the
intake/exhaust systems carry out the exhaust gas
recirculation process, and effectively limit the Nox
constituent in emissions.

Fig. 2-1-5 Turbocharging System

4. Turbocharging System

The turbocharging system of engine is as shown in Fig.
2-1-5.

The function of the turbocharging system is to compress
the air from the air filter through the turbocharger and
then sent the compressed air into cylinder by use of the
exhaust gas energy. Although the working volume of the
cylinder does not change, the air density increases after
compression, and therefore the volume of the actual
intake air increases. In this way, the fuel injected into the
cylinder increases and the fuel burns more fully, and
therefore the power per liter and output power of the
diesel engine are improved.

Fig. 2-1-6 Fuel Supply System

5. Fuel Supply System

The fuel supply system of engine is as shown in Fig.
2-1-6.

According to the work requirements of the diesel
engine, the fuel supply system regularly injects diesel
into the combustion chamber at a specified quantity and
pressure to provide necessary conditions for sufficient
combustion of diesel; at the same time, it adjusts the oil
supply quantity according to the loading condition of the
diesel engine, and ensures a steady output power. The
fuel supply system mainly consists of the fuel tank, fuel
filter, fuel delivery pump, high pressure fuel pump, high
pressure fuel rail, fuel injector, high/low pressure fuel
pipe, and all kinds of sensors, etc.

Cylinder head
installation assembly

Cylinder body

Turbocharger assembly

Oil return hose

component

Oil inlet pipe

component

High

pressure

oil rail

assembly

Oil

injector

assembly

High pressure oil

pump assembly

Cylinder head

Air intake manifold

Cylinder head
installation assembly

Exhaust manifold

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

11

Fig. 2-1-7 Lubrication System

6. Lubrication System

The lubrication system of engine is as shown in Fig.
2-1-7.

The lubrication system is mainly used to transport
lubricating oil to friction surfaces of all moving parts of
the diesel engine to ensure the lubrication of kinematic
pairs of all engine parts, and reduce friction resistance
and wear of machine elements; it also has other
functions such as cooling, cleaning, sealing and rust
prevention. The lubrication system is mainly composed
of the oil collector, oil pump, oil filter, oil cooler, oil
pressure alarm, lubricating oil pipeline, etc.

Fig. 2-1-8 Cooling System

7. Cooling System

The cooling system of engine is as shown in Fig. 2-1-8.
When the diesel engine is working, the cooling system

radiates excessive heat from the heated parts to keep
the normal working temperature of the diesel engine.
The major components of the cooling system include:
the water tank (radiator), liquid storage tank (overflow
tank), water pump, thermostat, fan, etc.

8. Startup Device

The startup device of engine is as shown in Fig. 2-1-9.
With the action of external force, the startup device

makes the stationary diesel engine begin to rotate
before it can rotate independently. The startup device is
constituted of the starting motor, storage battery, heater
plug and other devices.

In conclusion, the cylinder body, cylinder head, crank
and connecting rod mechanism, valve actuating
mechanism, intake/exhaust systems and fuel supply
system work in coordination with each other and fulfill
the working cycle of the diesel engine directly to
accomplish the transformation of energies. During
operation, the technical conditions of these components
and whether they coordinate with each other correctly

have decisive influences on the engine’s performance.

The lubrication system and cooling system do not
accomplish the working cycle directly; however, they are
indispensable conditions for the long-term and steady
working of the diesel engine. While the startup device
provides an initial condition for the stationary diesel
engine to rotate, therefore sufficient attention should be
given to their working conditions. Otherwise, the normal
work of the diesel engine can not be ensured or serious
damage to engine parts may be caused.

Fig. 2-1-9 Startup Device

Cylinder body

Engine oil filter

Cylinder body

Water pump
installation
assembly

Thermostat assembly

Starting motor

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Section II View of Engine

1. Front View of Engine

For the front view of GW4D20 turbocharged diesel engine assembly, see Fig. 2-2-1.

Fig. 2-2-1 Front View of GW4D20 Turbocharged Diesel Engine Assembly

(Equipped with Delphi Common Rail System)

1-Accessory Tension Pulley Assembly; 2-Generator Assembly; 3-Generator Belt; 4-Power Steering Fuel

Pump Assembly; 5-Air Intake of Gas Compressor; 6-Water outlet Pipe Mouthpiece; 7-Timing Hood;

8-EGR Valve Assembly; 9-Engine Oil Dipstick Assembly; 10-Accessory Wedge Idle Wheel Assembly;

11-Accessory Flat Idle wheel Assembly; 12-Refrigeration Compressor Assembly; 13-Damping Pulley

Assembly

Chapter II Technical Information of Engine

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13

2. Rear View of Engine

For the rear view of GW4D20 turbocharged diesel engine assembly, see Fig. 2-2-2.

Fig. 2-2-2 Rear View of GW4D20 Turbocharged Diesel Engine Assembly

(Equipped with Delphi Common Rail System)

1-Clutch Assembly; 2-Starting Motor Assembly; 3-EGR Condenser Assembly; 4-EGR Valve Assembly;

5-Fuel Inlet of High Pressure Fuel Pump; 6-Coolant Temperature Sensor; 7-Vacuum Pump Assembly;

8-Heater Water Return Outlet; 9-Heater Water Inlet; 10-Water Outlet Pipe Assembly; 11-Hex Head

Screw Plug (Oil Drain Screw Plug); 12-Lower Shell Assembly of Fuel Pan

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3. Left View of Engine

For the left view of GW4D20 turbocharged diesel engine assembly, see Fig. 2-3-3.

Fig. 2-2-3 Left View of GW4D20 Turbocharged Diesel Engine Assembly

(Equipped with Delphi Common Rail System)

1-Refrigeration Compressor Assembly; 2-Water Inlet; 3-High Pressure Fuel Pump Assembly; 4-Knock

Sensor; 5-Air Intake Manifold; 6-Air Inlet; 7-Turbocharged Pressure Sensor; 8-EGR Valve Assembly;

9-Flywheel Gear Ring Assembly; 10-Starting Motor Assembly; 11-Left Bracket of Engine

Chapter II Technical Information of Engine

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15

4. Right View of Engine

For the right view of GW4D20 turbocharged diesel engine assembly, see Fig. 2-2-4.

Fig. 2-2-3 Right View of GW4D20 Turbocharged Diesel Engine Assembly

(Equipped with Delphi Common Rail System)

1-Engine Lifting Hook; 2-Turbocharger Assembly; 3-Air Outlet of Air Compressor; 4-Oil Filter Assembly;

5-Timing CoverⅠ; 6-Upper Shell Assembly of Oil Pan; 7-Lower Shell Assembly of Fuel Pan; 8-Right

Bracket of Engine; 9-Oil Pressure Alarm; 10-Crankshaft Position Sensor

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5. Vertical View of Engine

For the vertical view of GW4D20 turbocharged diesel engine assembly, see Fig. 2-2-5.

Fig. 2-2-3 Vertical View of GW4D20 Turbocharged Diesel Engine Assembly

(Equipped with Delphi Common Rail System)

1-Fuel Injector Assembly; 2-Suppercharger Assembly; 3-Water outlet Pipe Component; 4-Heater Water

Return Pipe Component; 5-High Pressure Fuel Rail Pressure Sensor; 6-High Pressure Fuel Rail; 7-EGR

Valve Assembly; 8-Turbocharged Pressure Sensor; 9-Fuel Filler Cap Assembly; 10-Fuel Inlet Pipe

Component of Fuel Rail; 11-Engine Oil Dipstick Assembly; 12-Generator Belt; 13-Fuel Inlet Pipe

Component of Fuel Injector; 14-Fuel Injector Ballast; 15-Upper Shell Assembly of Fuel Pan;

16-Generator Assembly

Chapter II Technical Information of Engine

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Manufacturing Company Limited

17

Section III Main Performance Indexes of Engine

The indexes used to evaluate and analyze the engine performance mainly include the power
performance, economical efficiency, applicability, low public hazard, etc.; every index contains several
items, and here we only introduce the indexes that are commonly used:

1. Power Performance Index

(1) Effective torque: refers to the torque that is output through the engine flywheel; it is balanced to the
external resistance moment which is exerted on the power output end of engine. It is represented by Me,
and the unit is N•m.

(2) Effective power: refers to the power output by the engine. It is represented by Pe, and the unit is kW.
It is calculated by multiplying the effective torque by the crankshaft rotation speed:

Where, Me ——Effective torque (N·m).
n ——Crankshaft rotation speed (r/min).
The effective torque and the crankshaft rotation speed are usually measured with a hydraulic or electric

dynamometer directly; the effective power is calculated by Pe=Me·n/9550 (kW), which indicates the
effective power under the tested working condition.

The effective power and corresponding rotation speed under the calibrated working condition indicated
on the engine nameplate are called the calibrated power and calibrated rotation speed. Presently, the
calibrated power of engine is divided into four grades according to the national standards:

(1) 15min power: the Max. effective power of engine when the engine constantly rotates for 15 minutes
under the standard environmental condition.

(2) 1h power: the Max. effective power of engine when the engine constantly rotates for 1 hour under the
standard environmental condition.

(3) 12h power: the Max. effective power of engine when the engine constantly rotates for 12 hours under
the standard environmental condition.

(4) Continuous power: the Max. effective power of engine when the engine continuously rotates at the
calibrated rotation speed under the standard environmental condition,.

Generally speaking, the 15min power is applied to the power calibration of vehicle, motorcycle,
motorboat, etc.; 1h power is applied to the industrial tractor, engineering machinery, diesel locomotive,
etc.; 12h power is applied to the agricultural tractor, agricultural irrigation and drainage machinery, and
river vessel, etc.; continuous power is applied to the power station, vessel, and agricultural irrigation and
drainage machinery, etc.

2. Economical Efficiency Index

Currently, the frequently used comparative evaluation index is the fuel consumption rate which refers to
the fuel mass consumed by the engine in an hour. It is represented by ge, and the unit is g/kW·h:

ge=G/P.·103(g/kW·h)
Where, G ——Fuel consumption per hour (kz/h) obtained by testing.
P ——Effective power of engine (kW).
Attention has always been taking for the reduction of fuel consumption since it has great significance for

decreasing engine application costs, promoting rational use of resources, improving the ecological
environment, etc., and the fuel consumption is decreasing year by year.

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3. Reliability and Durability Index

3.1 Reliability

Reliability of the engine means the engine can work continuously and its normal working ability is not
influenced by malfunctions under the designed working condition. In China, the reliability of engine is
normally represented by non-stop malfunction times, stop malfunction times and number of major parts
and minor parts replaced during the warranty period (or insurance period).

The major parts include: the cylinder head, piston, piston ring, piston pin, connecting rod, connecting rod
bearing bush, connecting rod bolt, crankshaft, engine body, camshaft, intake and exhaust valves, valve
spring, rocker arm, high pressure fuel pump, oil pump gear, driving gear, turbocharger, etc. The rest are
minor parts.

3.2 Durability

The durability index refers to the total operation hours of the engine or the driving kilometers of the
vehicle from the initial use of engine to the first overhaul. It is the index that represents the service life of
engine. Now, the durability of the domestic small-sized high-speed diesel engine is 2000 ~ 3000 h, and
the high-speed internal combustion engine for vehicle is 100000 ~ 200000 km.

4. Low Public Hazard Index

The poisonous emissions and noises from engine are harmful to human health and have negative
influences on working efficiency, so China and other counties have established more and more strict
controlling standards to protect the normal ecological environment for human beings. The poisonous
gases produced by the engine during working mainly come from the exhaust gas, blowby from the
crankcase, and vaporized gases from the fuel tank, fuel pipe connector, etc. The exhaust gas from
engine contains many compositions, including CO2, steam, surplus oxygen, residual nitrogen, CO, HC,
Nox, S02 and particles such as aluminide, black smoke, oil mist, etc.. and stinking gases such as
formaldehyde, acrolein, etc. The blowby from the crankcase mainly includes HC, CO and so on, and the
main vaporized gas from the oil tank is HC. The total amount of the above exhaust pollutants takes up
about 1％ of the exhaust gas from the engine. Most of them are poisonous and harmful, with strong
pungency, a stinking odor and carcinogenesis.

There is no uniform international emission regulation at present, China and other countries have
established their own emission control standards to control the emission of poisonous CO, HC, NOx and
the smoke density.

China promulgated ―Law on Prevention of Air Pollution‖ in 1987 and then promulgated the GB engine

exhaust standard to limit the poisonous emissions from the engine. Compared with those of the
developed countries, the domestic controlling standards for poisonous engine emissions are looser, but
they will get stricter and stricter and will joint with the international standards gradually from the
perspective of its developing trend.

China promulgated Regulation on Prevention and Control of Environment Noise Pollution in 1988.The
engine is widely used as the power source, and its exhaust gases and noises have the largest
environmental pollution area, and therefore attracting more and more attention from the public.

Chapter II Technical Information of Engine

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Manufacturing Company Limited

19

Rotation speed

(r/min)

Section IV Engine Property Curves

For the power, torque property curves of the GW4D20 turbocharged diesel engine, see Fig. 2-4-1.

Fig. 2-4-1 Power, Torque Property Curves of GW4D20 Turbocharged Diesel Engine

ge ——Fuel consumption rate (g/kW·h); G ——Fuel consumption volume (kg/h); P ——Effective power

For the power, torque property curves of the GW4D20B turbocharged diesel engine, see Fig. 2-4-2.

(kW); Me ——Effective torque (N·m)

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Rotation speed

(r/min)

Fig. 2-4-2 Power, Torque Property Curves of GW4D20B Turbocharged Diesel Engine

ge ——Fuel consumption rate (g/kW·h); G ——Fuel consumption volume (kg/h); P ——Effective power

(kW); Me ——Effective torque (N·m)

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

21

Item

Unit

Technical Parameter

Model No.

GW4D20/GW4D20B

Type

Cylinders in line, four strokes, forced cooling, ω

combustion chamber, 16 valves, DOHC, electric
control high-pressure common rail, turbocharged
(VGT, WGT), air intake intercooled

Number of Cylinders

cylinder

4

Cylinder Diameter X Stroke

mm

83.1×92

Total Displacement

L

1.996

Compression Ratio 16.7:1

Rated Power and Corresponding
Rotation Speed

r/min

110/4000 GW4D20

100/4000 GW4D20B

Max. Torque and Corresponding
Rotation Speed

N·m/

(r/min)

310/1800~2800

Min. Fuel Consumption Rate

g/kW·h

210

Max. No-load Rotation Speed

r/min

4400

Idle Rotation Speed

r/min

750±50

Fuel China IV diesel without nitro additives

Fuel Grade

0# vehicle fuel (-10# or -20#, -35# diesel can be used
in winter according to temperatures) (GB19147-2009)

Air Valve Clearance 0 (hydraulic tappet)

Fuel Injection Sequence 1—3—4—2

Rotation Direction (viewing from the
flywheel end)

Anticlockwise

Max. Fuel Injection Pressure

Bar

1600

Oil Injection Control Electric control

Valve
Actuating
Phase
(℃A)

Intake valve opened
(before the piston
arrives at the top dead
center (TDC))

℃A

24°

Intake valve closed
(after the piston arrives
at the bottom dead
center (BDC))

℃A

50°
Exhaust valve open
(before piston arrives at
BDC)

℃A

86°

Exhaust valve closed
(after the piston arrives
at the TDC)

℃A

16°

Section V Technical Data and Specifications of Engine

1. Technical Parameters of Engine

For the main technical parameters of the GW4D20/GW4D20B turbocharged diesel engine, see Table
2-5-1.

Table 2-5-1 Main Technical Parameters of GW4D20/GW4D20B Turbocharged Diesel Engine

Note. ①1 bar = 105 Pa.

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Item

Unit

Technical Parameter

Lubrication Mode

Pressure and splash combination type

Fuel Grade

API CI-4

Engine Oil Capacity L 6

Oil/fuel Consumption Ratio

%

≤ 0.3% (rated power point)

Cooling Mode

Forced circulating water cooling

Coolant High quality ethylene glycol coolant

Diesel Engine Coolant Capacity

L

3

Normal, Max. working water
temperatures of the diesel engine,
opening temperature of large and
small cycles, and water circulation
direction

Normal water temperature: 80 ℃ ~ 90 ℃; Max.
water temperature: 110 ℃; thermostat full opening
temperature: 80 ℃ (the thermostat is located at
the water inlet)

Net mass of diesel engine (including
the air condition compressor, power
steering oil pump, cooling water)

kg

215 GW4D20

210 GW4D20B

Contour Dimensions (L x W x H),
transmission excluded

mm

694×625×829 GW4D20

694×615×829 GW4D20B

Turbocharger
Max. rotation speed

r/min

210000

Max. durative
working
temperature

℃

Noise Acoustic Power Limits

dB/A

760 VGT/750 WGT

Exhaust Pollutants Limits

g/km

≤ 110 (complying with GB 14097-1999)

Complying with GB 18352.3-2005

(Continued)

For the technical parameters of the main parts of GBWD20/GW4D20B turbocharged diesel engine
electric system, see Table 2-5-2.

Chapter II Technical Information of Engine

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Manufacturing Company Limited

23

Item

Unit

Technical Parameter

Generator

Nominal voltage V 12

Rated rotation speed

r/min

5000

Service speed

r/min

900~11000

Rotation direction

Clockwise (viewing from the direction of pulley)

Polarity Cathode earthing

Working mode

Continuous rated type

High speed voltage of

regulator

V

14.5±0.3

Starting

Motor

Voltage

V

12

Output power

kW

2

Rotation direction

Clockwise (viewing from the direction of driving

gear)

Item

Unit

Technical Parameter

Storage

Battery

Rated voltage

V

14

Heater Plug

Heating time

s

Heated to 800 ℃ in 8 s

Item

Temperature Range

Item

Pressure Range

Water Outlet of Cooling

System

80℃~90℃

Idle engine oil pressure

≥0.3Mpa

Engine Oil of

Lubrication System

≤120℃

Engine oil pressure at

the calibrated rotation

speed

≥0.4Mpa

Table 2-5-2 Technical Parameters of Main Parts of GBWD20/GW4D20B Turbocharged Diesel

Engine Electric System

(Continued)

2. Various Temperature and Pressure Ranges of Engine

For various temperature and pressure ranges of GW4D20/GW4D20B turbocharged diesel engine, see
Table 2-5-3.

Table 2-5-3 Various Temperature and Pressure Ranges of GW4D20/GW4D20B Turbocharged

Diesel Engine

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Accessory System and Name

Specification

Accessory System and Name

Specification

Lubrication

System

Oil pump

Rotor type

Air intake

system

Turbocharger

VGT

Cross-section

variable type
turbocharger

Engine oil filter

Rotary type

WGT

Turbocharger

with bypass

valve

Oil Supply

System

Fuel filter

DELPHI

Integral type:

equipped with

fuel-water
separator

Cooling

system

Water pump type

Centrifugal

type

BOSCH

Rotary installation

type: equipped

with fuel-water

separator

Pumping lift (4500

r/min)

16m

Xin Feng

Rotary installation

type: equipped

with fuel-water

separator

High

pressure

fuel pump

DELPHI

Double plungers,

equipped with fan

blade pump, IMV

Thermostat type

Wax-type

thermostat

BOSCH

Triplex plunger

pump

Xin Feng

Double plunger

pump

Vacuum

pump

Working mode

Continuous

rated type

High

pressure

fuel rail

DELPHI

Max. oil supply

pressure 1600 bar

BOSCH

Max. fuel supply

pressure 1600bar

Max. rotation speed

2800

Xin Feng

Max. fuel supply

pressure 1600 bar

Fuel

injector

type

DELPHI

7-hole

Max. vacuum degree

90

BOSCH

6-hole

Time for achieving

the vacuum degree

Time for

achieving 50

kPa ＜ 5

(400r/min）

Xin Feng

6-hole

3. Specifications of Main Engine Accessories

For the specifications of main accessories of GW4D20/GW4D20B turbocharged diesel engine, see
Table 2-5-4.

Table 2-5-4 Specifications of Main Accessories of GW4D20/GW4D20B Turbocharged Diesel

Engine

Note. ①1 bar=105 Pa.

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

25

Parts Name

Installation Position

Specification

High Pressure Fuel

Pump

Rear end face of water

pump housing

DELPHI

Double plunger,

equipped with fan blade

pump, IMV

BOSCH

Triplex plunger pump

Xin Feng

Double plunger pump

Fuel injector

Top surface of cylinder

head

DELPHI

7-hole

BOSCH

6-hole

Xin Feng

6-hole

High pressure fuel rail

Left side of cylinder

body

DELPHI

Max. fuel supply

pressure 1600 bar

BOSCH

Max. fuel supply

pressure 1600 bar

Xin Feng

Max. fuel supply

pressure 1600 bar

Electronic Control Unit

(ECU)

Inside the engine hood

Working voltage 12 V

Rotation Speed Sensor

Upper cylinder body

Working clearance 0.5 ~ 1.5 mm

Camshaft Phase

Sensor

Cylinder head cover

Working clearance 0.5~1.5mm

Water Temperature

Sensor

Cylinder head

Rated voltage: 5 V ± 0.15 V, NTC-type, rated

resistance: 2.5 kΩ ± 0.6% at 20 ℃ and 0.186 kΩ ±

2% at 100 ℃

Air Intake Pressure

Sensor

Air intake manifold

DS-S3

Heater Plug

Lateral surface of

cylinder head

Heated to 800 ℃ in 8 s

EGR Valve

Rear end of air intake

manifold

Vacuum type

Fuel filter

Frame

Equipped with manual fuel delivery pump,

fuel-water separator, diesel heater (flow rate: 125

L/h), particle filterability of paper filter core: ＞15

μm100%, 3~5 μm 94.5%, replacement period of

filter core: every 25000 ~ 30000 km of driving

range

4. Specifications of Main Parts of Fuel Supply System

For the specifications of main parts of GW4D20/GW4D20B turbocharged diesel engine fuel supply
system, see Table 2-5-5.

Table 2-5-5 Specifications of Main Parts of GW4D20/GW4D20B Turbocharged Diesel Engine Fuel

Supply System

Note. ①1 bar=105 Pa.

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Sequence

No.

Parts Code

Parts Name and

Specification

Installation

Position

Tightening Torque

Value (N·m)

1

1004303—ED01

Connecting rod

bolt

Connecting rod

——connecting rod

cap

25 ± 3, rotation angle

90° ± 5°

2

1003700—ED01

Bolt and washer

component of

cylinder head

Cylinder body

——cylinder head

gasket ——cylinder

head

50 ± 3, rotation angle

90°, rotating an

additional 120°

3

1021800—ED01

Bolt and washer

component of

camshaft timing

pulley

Camshaft pulley

——camshaft

110±5

4

1005011—ED01

Flywheel bolt

Flywheel

——camshaft

75±5

5

1002116—ED01

Main bearing cap

bolt

Cylinder body

——main bearing

cap

40 ± 3, rotation angle

90°, rotating an

additional 90°

6

1021014 一 ED01

Bolt of crankshaft

timing pulley

Crankshaft timing

pulley

——crankshaft

185~195

7

Q1840820F32

Hexagonal flange

face bolt

Damping pulley of

crankshaft

——crankshaft

23±3

8

1009106—ED01A

Fuel drain bolt (hex

Fuel pan assembly

40±5

Section VI Maintenance Standard for Engine

The normal operation of engine usually means: the consumption rates of fuel and lubricating oil conform
with the design specifications, and the engine is capable of producing its designed power and running
smoothly without abnormal noise. Any abnormal phenomenon has a relation with the fitting condition of
the kinematic pair of engine. There are strict technical requirements for the assembly of kinematic pairs
of engine; the geometric shape, fit clearance, surface roughness and cleanliness of parts should
conform with the requirements. When the matching parts are installed, certain precisions should be
applied, and the fit clearances are especially important. If the clearance is too small, the engine can not
run smoothly, which accompanied with friction increasing, overheat, galling, even blockage if serious; if
the clearance is too big, it may create impact and noise shortly after the parts are used, and result in
difficulty in forming lubricating oil film, thus decreases the service life of parts. For the diesel engine that
is put into service after strict assembly and running-in, its service life lies on proper maintenance.

1. Tightening Torque of Main Fasteners of Engine

For the tightening torque of main fasteners of GW4D20/GW4D20B turbocharged diesel engine, see
Table 2-6-1.

Table 2-6-1 Tightening Torque of Main Fasteners of GW4D20/GW4D20B Turbocharged Diesel

Engine

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

27

Sequence

No.

Parts Code

Parts Name and

Specification

Installation

Position

Tightening Torque

Value (N·m)

head screw plug)

9

101701l—ED01

Filter pipe

connector

Cylinder body

——filter

50~60

10

3611070—ED01

Coolant

temperature

sensor (water

temperature

sensor)

Cylinder head

18~22

11

1021031 一 ED01

Fastening bolt of
timing idle wheel

Timing idle wheel

——oil pump

43±4

12

1002800—ED01

Oil pressure alarm

Upper cylinder body

13~17

13

1021032 一 ED01

Fastening

combination bolt of

timing tension

pulley

Timing tension

pulley ——cylinder

head

22~26

14

3701014 一 ED01

Fastening bolt of

accessory idle

wheel

Oil pump ——timing

hood

22~26

15

3701016 一 ED01

Fastening bolt of

accessory tension

pulley

Compressor support

53~57

16

3770100—ED01

Heater plug

assembly

Cylinder head

9~12

17

Q33014T13F2

All-metal

hexagonal

flange-face locknut

(M14X1.5)

High pressure oil

pump pulley

——high pressure

fuel pump

65±3

18

1118013 一 ED01

1118013 一 ED01B

Fuel intake bolt of

turbocharger

Fuel intake pipe

——turbocharger

Fuel intake pipe

——cylinder block

22±3

19

Q618B02F32

Hex head tapered
screw plug (water

drain screw plug)

Upper cylinder body

25±3

20

Q32008F32

Hexagonal flange

face nut

Exhaust manifold

——cylinder head

30±3

For the tightening torque standards for general fasteners of GW4D20/GW4D20B turbocharged diesel
engine, see Table 2-6-2.

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Sequence

No.

Fastener

Specification

Torque

Limit

(N·m)

Remarks

Sequence

No.

Fastener

Specification

Torque

Limit

(N·m)

Remarks

1

M6 x1

9±3

Performance

grade 8.8,

please refer to

QC／T

518-1999

4

M10 x1

45±3

Performance

grade 8.8,

please refer to

QC／T

518-1999

2

M8 x1

25±3

5

M10 x1.25

45±3

3

M8 x1.25

23±3

6

M12 x1.75

95±10

Sequence

No.

Name of Fit Clearance of Parts

Fit Clearance Value (mm)

Remarks

1

Camshaft axial clearance

0.060~0.115

See Page 153, 210,

220, 230, 293

2

Crankshaft axial clearance

0.10~0.28

See Page 131, 165,

275, 288

3

Side clearance between piston ring

and piston ring groove

0.055 ~ 0.100 (the first
compression ring)

0.035 ~ 0.080 (the second
compression ring)

0.030 ~ 0.070 (oil ring
component)

See Page 147, 150,

257

4

Opening clearance of piston ring

0.20 ~ 0.40 (the first
compression ring)

0.65~0.85 (the second
compression ring)

0.25 ~ 0.50 (oil ring
component)

See Page 146, 150,

257

5

Clearance between big end of

connecting rod and crankshaft crank

0.22~0.37

See Page 151, 258,

276, 290

6

Piston cylinder clearance

0.07~0.09

See Page 150, 258,

276, 290

7

Clearance between piston pin and

piston pin hole

0.005~0.012

See Page 147, 149

8

Clearance between piston pin and

connecting rod small end hole

0.010~0.024

See Page 147, 149

Table 2-6-2 Tightening Torque Standards for General Fasteners of GW4D20/GW4D20B

Turbocharged Diesel Engine

2. Fit Clearance of Main Parts of Engine

For the fit clearances of main parts of GW4D20/GW4D20B turbocharged diesel engine, see Table 2-6-3.

Table 2-6-3 Fit Clearances of Main Parts of GW4D20/GW4D20B Turbocharged Diesel Engine.

For the matching selection by group for the main shaft bearing shell of the turbocharged diesel engine
GW4D20/GW4D20B , see Table 2-6-4.

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

29

Color of Main Bearing Shell

Main bearing journal of crankshaft

1 2 3

φ60.015~φ60.020

φ60.009~φ60.014

φ60.002~φ60.008

Main

Bearing

Aperture

of

Cylinder

Body

1

φ64.000~φ64.006

Yellow

Thickness of

shell: 1.976

~ 1.980

Clearance:

0.020 ~

0.040

Yellow

Thickness of

shell: 1.976

~ 1.980

Clearance:

0.026 ~

0.046

N/A

Thickness of

shell: 1.980 ~

1.984

Clearance:

0.024 ~

0.044

2

φ64.007~φ64.012

Yellow

Thickness of

shell: 1.976

~ 1.980

Clearance:

0.026 ~

0.046

N/A

Thickness of

shell: 1.980

~ 1.984

Clearance:

0.024 ~

0.044

Blue

Thickness of

shell: 1.984 ~

1.988

Clearance:

0.022 ~

0.042

3

φ64.013~φ64.018

N/A

Thickness of

shell: 1.980

~ 1.984

Clearance:

0.024 ~

0.044

Blue

Thickness of

shell: 1.984

~ 1.988

Clearance:

0.022 ~

0.042

Blue

Thickness of

shell:

1.984~1.988
Clearance:

0.022 ~

0.042

Group No. of Main Bearing

Hole of Cylinder Body (1, 2, 3)

Group No. of Main Crankshaft

Journal (1, 2, 3)

Main shaft bearing shell color

code (number)

Fit Clearance

=1-3

Yellow (1)

0.020~0.046 mm

=4

None (2)

0.024~0.044 mm

=5-6

Blue (3)

0.022~0.048 mm

Table 2-6-4 Matching Selection by Group for the Main Shaft Bearing Shell of the Turbocharged

Diesel Engine GW4D20/GW4D20B Unit: mm

For the matching selection for the main shaft bearing shell of the turbocharged diesel engine
GW4D20/GW4D20B, see Table 2-6-5.

Table 2-6-5 Matching selection for the Main Shaft Bearing Shell of the Turbocharged Diesel

Engine GW4D20/GW4D20B

For the matching selection by group of cylinder Bores and pistons, see table 2-6-6.

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cylinder Bore

Dimension (φ)

Mark

Piston Dimension by Group

Mark

Fit Clearance

83.09~83.10 mm

1

83.1

0.081

0.090




-0.090mm

1

0.071~0.090 mm

83.10~83.11 mm

2

83.1

0.071

0.080




-0.090mm

2

0.071~0.090 mm

83.11~83.12 mm

3

83.1

0.061

0.070




-0.090mm

3

0.071~0.090 mm

Sequence

No.

Position for Daubing or Injecting

Lubrication Oil on Assembly Parts

Remarks

1

Working surface of main bearing shell

See Page 133, 165, 274, 288

2

Main journal and oil hole

See Page 134, 165, 274, 288

3

Between crankshaft thrust plate and crank

arm thrust face

See Page 135, 165, 275, 289

4

Cylinder bore wall

See Page 135, 150, 166, 257, 276, 289

5

Internal surface of connecting rod bearing

shell and surface of crankshaft crank pin

See Page 136, 150, 166, 257, 276, 289

6

Surface of piston pin hole, piston ring groove,

piston pin surface, connecting rod small end

hole

See Page 136, 149, 257, 276, 290

7

Internal surface of bearing hole of the

intake/exhaust camshaft of cylinder head,

surface of camshaft journal

See Page 107, 117, 139, 203, 210, 220,

230, 259, 279

8

Camshaft

See Page 107, 117, 139, 203, 210, 220,

230, 259, 279

9

Mounting hole of hydraulic tappet, and the

surface of tappet

See Page 106, 127, 139, 152, 210, 229,

279, 259, 293

10

Valve guide hole and valve stem

See Page 105, 127, 219

11

Oil pump shaft and outer and inner rotors

See Page 137, 245, 336

12

Oil seal lip

See Page 135, 158, 166, 245, 336

Table 2-6-6 Matching Selection by Group of Cylinder Bores and Pistons

For positions for daubing or injecting lubricating oil on assembly parts of GW4D20/GW4D20B
turbocharged diesel engine, see Table 2-6-7.

Table 2-6-7 Positions for Daubing or Injecting Lubricating oil on Engine Assembly Parts

(Mobil Oil Corp., API CI-4 Plus diesel engine oil)

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

31

Sequence

No.

Position for Coating Sealant

Name of the Coated

Sealant

Specification and Model

1

Joint surface between oil pump

and cylinder body/fuel pan

Silicon rubber flat

sealant

LOCTITE 587 flat sealant

2

Joint surface between fuel pan

and lower cylinder body

Silicon rubber flat

sealant

LOCTITE 587 flat sealant

3

Joint surface between upper

fuel pan and lower fuel pan

Silicon rubber flat

sealant

LOCTITE 587 flat sealant

4

Joint surface between upper

cylinder body and lower

cylinder body

Anaerobic flat sealant

LOCTITE 510 anaerobic flat

sealant

5

Joint surface between cylinder

head and camshaft bearing

cap

Anaerobic flag

sealant

LOCTITE 510 anaerobic flat

sealant

6

Threaded section of water

drain screw plug

Anaerobic thread

fixing sealant

LOCTITE 243 thread fixative

7

Threaded section of oil

pressure alarm assembly

Anaerobic thread

fixing sealant

LOCTITE 243 thread fixative

8

Threaded section of water

temperature sensor

Anaerobic thread

fixing sealant

LOCTITE 243 thread fixative

9

Water outlet pipe component,

heater water return pipe

connector, and all pipe

connectors on cylinder body

Anaerobic fixative for

cylindrical parts

TONSAN 1608 sealing fixative

for bowl-shaped plugs

10

bowl-shaped plugs on cylinder

body and cylinder head

Anaerobic fixative for

cylindrical parts

TONSAN 1608 sealing fixative

for bowl-shaped plugs

Item

Capacity

Recommended Lubricating oil Grades

Total Engine Oil

Amount

Replace Oil Filter

Replace the

Compete Machine

Oil

6.0 L

Refill 0.5 L

5.0 L

Mobil Oil Corp., API CI-4 Plus diesel engine oil (choose

according to the ambient temperature)

Table 2-6-8 Position for Coating Sealant on Engine Assembly Parts

For the oil filling capacity of GW4D20/GW4D20B turbocharged diesel engine, see Table 2-6-9.

Table 2-6-9 Lubricating oil Capacity of Engine

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Vehicle Traveling

Distance (km)

Vehicle Load

Rotation Speed of Diesel Engine (r/min)

0~300

No-load

Not over 50% the rated rotation speed of the

corresponding diesel engine

＞301~1000

Not over 50% of the rated

load

Not over 50% the rated rotation speed of the

corresponding diesel engine

＞1001~1500

Not over 50% of the rated

load

Not over 75% of the rated rotation speed of the

corresponding diesel engine

＞1501~2500

Full load

Not over the rated Max. rotation speed of diesel

engine

Section VII Running-in of Engine

The new diesel engine or diesel engine just overhauled (including replacements of the piston, piston ring
or main bearing shell, connecting rod bearing shell) should go through a running-in period during which
the engine should start from a low load to a high load gradually before normal use, and the initial check,
adjustment and maintenance should be carried out during the running-in. Try to make all kinematic pairs
run-in well and prevent abnormal wear and damage. The experiences have testified that the service life,
working reliability and economical efficiency of the diesel engine, to a large extent, lie on the running-in
condition of the diesel engine in the initial stage of use.

1. Preparation Before Running-in

1.1 Operators should read the Use and Maintenance Manual for GW4D20/GW4D20B Turbocharged
Diesel Engine carefully to be familiar with the structure, performance, operation and maintenance

methods of the engine.

1.2 Clear up the external surface of diesel engine.

1.3 Check the oil level, and refill oil to the specified oil level if the oil is not enough.

1.4 Check and refill fuel (vehicle diesel), coolant (anti-freezing, anti-rust liquid).

1.5 Check the electrolyte level of the storage battery, and refill to the specified level if the electrolyte is
not sufficient.

1.6 Check if the timing belt is installed properly and if the timing mark is correct.

1.7 Check if the electric line, ECU and harness assembly are correctly and securely connected.

1.8 Set the operating handle of gear box to Neutral.

2. Running-in

Before engaged in work with normal load, the new diesel engine should run-in on the vehicle for 2500
km according to the running-in specification, see Table 2-7-1) or on the test rack for 50 h according to the
running-in specification.

The diesel engine whose piston, piston ring, main bearing shell, connecting rod bearing shell, etc. have
been replaced during the overhaul should run-in on the vehicle for 500 km (according to Table 2-7-2) or
on the test rack for 10 h according to the running-in specification.

During the running-in period, you can carry out further inspection for the assembly quality of all engine
parts and implement adjustment when necessary.

Table 2-7-1 Specification for New Diesel Engine’s Running-in on Vehicle

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

33

Vehicle Traveling

Distance (km)

Vehicle Load

Rotation Speed of Diesel Engine (r/min)

0~100

No-load

Not over 50% of the rated rotation speed of the

corresponding diesel engine

＞101~250

Not over 50% of the rated

load

Not over 50% of the rated rotation speed of the

corresponding diesel engine

＞251~450

Not over 75% of the rated

load

Not over 75% of the rated rotation speed of the

corresponding diesel engine

＞451~500

Full load

Not over the rated Max. rotation speed of diesel

engine.

Table 2-7-2 Specification for Diesel Engine’s Running-in on Vehicle (for the main parts replaced

during the overhaul)

3. Precautions for Running-in

3.1 You should observe, listen to the working condition of all systems of the diesel engine: check if there
is any oil, water, gas, or electric leakage; if the oil pressure, coolant temperature are normal; if the
rotation speed is steady; if the exhaust gas has a normal color; check the operation condition of
turbocharger, and make sure the rotor rotate flexibly, without block, clearance, etc. Any detected fault or
abnormal phenomena should be eliminated at first, and then proceed with running-in.

3.2 During running-in period, the vehicle should be driven at first or second level of road surface, it
should not be driving on road surface in bad condition, full speed and overspeed driving are absolutely
not permitted.

3.3 The max. allowed rotation speed of diesel engine during running-in period is 3000r/min.

4. Technical Maintenance After Running-in

A thorough inspection, clean-up and adjustment should be carried out after the completion of running-in
of the diesel engine, so as to eliminate the metal powder deposited in the lubricating oil and adjust the
improper clearance, the main contents are as follows:

4.1 After driving the vehicle for the first 2500 km (including the running-in period), discharge the engine
oil in the lubrication system and replace the oil filter, and replace the engine oil in accordance with
specified grades.

4.2 Check the fastening conditions of bolts, nuts of all parts; check the connection conditions of all
electrical connectors.

Attention: The diesel engine can only be put into service after running-in and maintenance

according to technical requirements. Or else it may shorten the service life of the diesel engine.

5. Precautions for Usage of New Vehicles

Driving a new vehicle in accordance with the following rules will not only elongate the service life of the
vehicle, but also reduce the diesel consumption.

5.1 Keep a normal coolant temperature (80 ℃ ~ 90 ℃; the temperature can be 105 ℃ when a pressure
water tank is used) and a normal oil pressure (≥ 0.4 MPa).

5.2 Keep the vehicle at a normal driving speed and prevent high speed driving.

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5.3 In the first 300 km of driving range, sudden stop should be avoided.

5.4 When the gear box is set at the high-speed gear, you should not drive the vehicle at a low speed.

5.5 Do not drive the vehicle at the high-speed gear or low-speed gear for a long time, you should shift
gears according to the driving condition at the right time.

5.6 When the driving range of a new vehicle reaches to 2500 km, besides daily maintenance, technical
maintenance should also be carried out according to the requirements of first-grade technical
maintenance; the engine oil and the oil filter should be replaced at the same time.

Section VIII Technical Maintenance for Engine

During the service of engines, due to wear of the parts, looseness of tightening parts, looseness of the
electrical connectors, change of clearance, oil deterioration, etc., the technical conditions of diesel
engine will degrade, a variety of abnormal phenomena such as hard starting, power loss, increase of oil
consumption will result, and even the engine can not operate normally. It is important to clean, check,
lubricate and adjust the various parts of the engine regularly and change some of the parts according to
the engine’s technical status and operating time or driving distance.

Attention: with the purpose of keeping a good technical condition, preventing or reducing
malfunctions and extending the service life of the engine, the technical maintenance must be carried out
seriously according to the specification.

1. Technical Maintenance Cycle

Various kinds of required regular maintenance operation are divided into 4 levels according to the
degrading degree of the parts of diesel engine:

1.1 Daily technical maintenance: usually at the end of each 8~10 h work shift.

1.2 First level technical maintenance: after the diesel engine operating time adds up to 100 h or the
vehicle driving distance adds up to 4000~5000 km.

1.3 Second level technical maintenance: after the diesel engine operating time adds up to 250 h or the
vehicle driving distance adds up to 10000 ~ 12500 km.

1.4 Third level technical maintenance: after the diesel engine operating time adds up to 1000 h or the

vehicle driving distance adds up to 50000 ~ 100000 km, or upon user’s own decision in accordance with

the working condition of diesel engine.
For the maintenance cycle of the GW4D20／GW4D20B turbocharged diesel engine, please refer to

Table 2-8-1.
According to technical maintenance requirements, the maintenance may be carried out in the procedure

of filling, cleaning, washing, adjusting, lubricating, repairing or replacing after check-up.

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

35

Maintenance

cycle

Maintenance
Items

Daily

technical

maintenance

First level

maintenance

Second level
maintenance

Third level

maintenance

Remarks

4000 ～

5000 km

4000 ～

12,500 km

4000 ～ 100,000

km

Diesel engine oil

Check the oil level

(recommended to check it

per 500 ~ 1000 km)

Replace the oil (normally per 8000

~ 10000 km)

Oil filter

Replace the oil filter (normally per

8000~10000km)

Fuel (diesel) filter

Replace the diesel filter (normally

per 20000 ~ 25000 km for

GW4D20 turbocharged diesel

engine)

Replace the diesel filter(normally

per 8000 ~ 10000 km for

GW4D20B turbocharged diesel

engine)

coolant

Check the fluid level

Air cleaner

clean

Normally, replace the filter core per

30000 km.

Parts and various

electrical
connectors
loosed and

damaged

Check, tighten, repair

Working condition

of diesel engine

Check if it operates normally

Four leakages

Check and remove oil leakage, water leakage, air leakage and

electricity leakage.

Appearance of

diesel engine

Keep clean

Belt of generator Inspect, adjust, replace

Connecting parts

of fuel pipes

loosed and

damaged

Check,

tighten,

repair

Radiator

clean

Connection of

turbocharger

Check, maintain

Fuel injector

Check or replace it when

malfunction displays

To check it in
a professional
service station

Timing driving

belt

Check the appearance of

driving belt

Replace the belt

(normally per

80000 ~ 100000

To repair it in
a professional
service station

Table 2-8-1 Maintenance Cycle for GW4D20／GW4D20B Turbocharged Diesel Engine

MAINTENANCE MANUAL OF GW4D20/GW4D20B TURBOCHARGED DIESEL ENGINES

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km)

Tension pulley,

accessory wedge

idle wheel and

flat idle wheel

Check,

maintain

when replacing the

belt, replace the

tension pulley
subassembly,

accessory wedge

idle wheel and flat

idle wheel

depending on the

their conditions

Replace the

tension pulley

after changing

the belt twice

Water pump

Check the water leakage of

overflow

Electrical

appliance

Check wiring, engine and starter

Crankcase vent

system (including

intake pipeline)

Check, wash

Maintenance

cycle

Maintenance
Items

Daily

technical

maintenance

First level

maintenance

Second level

maintenance

Third level

maintenance

Remarks

4000 ～
5000 km

10000 ～

12500 km

50000 ～ 100000

km

Washing the

cooling system

Wash the cooling

system

Washing the

engine

Wash the carbon

deposit, oil stains,

incrustation, oil

duct, oil pipe.

Piston ring

Inspect for wear

Depending on

the working
condition of

engine

Cylinder inner

wall

Inspect for wear

Connecting rod

bearing shell

Inspect for wear

Main shaft

bearing shell

Inspect for wear

Camshaft timing

driving gear

Inspect for wear

Thrust plate

Inspect for wear

Intake/exhaust

valve

Inspect for wear

Note: ① When the vehicle travels in a severe condition, traveling distance and time for replacing the oil
filter are: per 5000 km or per 100 h.

② If the diesel used contains impurities, the cycle for replacing the fuel filter should be shortened. If the
fuel filter is blocked by impurities, the fuel filter should be replaced in time.

(continued)

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Fig. 2-8-1 Checking the coolant level（for

reference only）

2. Technical Maintenance Contents

In order to ensure the engine operates properly,
technical maintenance should be carried out in the
following procedure:

2.1 Daily technical maintenance

(1) Inspect for the diesel fuel, coolant and oil level (see
Fig. 2-8-2), and add oil in accordance with technical
requirements if necessary.

Attention: correct inspection for various fluid levels
can only be carried out when the diesel engine is
stopped.

Fig. 2-8-2 Choosing fuel (vehicle diesel) in

accordance with the ambient temperature

Diesel specification: use the diesel which complies with
CBl9147-2009 provision, for south areas in winter (warm
zone) ——10# or 20#, for north areas (cold zone)
——35#.

For the areas with environment requirements, use the
diesel complying with environmental regulations.

Choose fuel in accordance with the season and local
temperature. See Fig. 2-8-2.

Attention: Never fill the fuel tank when the diesel
engine is running. If the vehicle is running in the hot
climate, the fuel tank should not be fully filled, or else the
fuel will overflow due to fuel extension; wipe the fuel as
soon as it overflows.

Inspect, add coolant.
Inspect the oil level.

Fig. 2-8-3 Checking the battery electrolyte

level

(2) Remove ash and electrolyte spilled on the battery to
make sure the vent hole unblocked. In normal conditions,
the battery almost needs no maintenance, but it needs to
be inspected regularly in high temperature conditions.
The fluid level should be between the Min. and Max.
marks on the side surface. The storage battery should be
filled with distilled water when the electrolyte is not
enough.

Caution: Never fill the battery with additional fluid
and other impure water optionally, or else it will cause
insufficient charging and affect usage. If the fluid level
drops fast, the storage battery should be sent to the
service station for repair.

Warning: the electrolyte is corrosive and must not
be splashed in eyes, on skin and clothes; clean it with
fresh water immediately if it is splashed on above
mentioned places.

Fluid
reservoir

GB 19147-2009 vehicle diesel

——– 35#

————20#

——– 10#

——0#

Ambient temperature for diesel
engine operation

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Fig. 2-8-4 Checking the connection between

the turbocharger and the diesel engine

Fig. 2-8-5 Measuring the electrolyte specific

gravity

Fig. 2-8-6 Measuring the battery voltage

(3) Check if there is oil, water, air or electricity leakage,
remove them if the ―four leakages‖ are found.

(4) Check if various accessory devices are fastened.
(5) After starting the engine, listen if the engine is running

properly, and check the working conditions of
instruments, they should be fixed or replaced if
damaged.

(6) Keep the diesel engine clean, especially pay attention
to that there should be no oil stains on the electrical
equipment and no foreign material on the radiator of
water tank.

(7) inspect and tighten the connection between the
turbocharger and diesel engine (see Fig. 2-8-4), remove
the malfunctions such as oil leakage, air leakage and so
on, and keep the surface of turbocharger clean.

Caution: If the diesel engine works in a dusty
condition, the air cleaner should be cleaned everyday to
ensure a good working condition for the air cleaner.

2.2 First class technical maintenance

On the basis of fulfilling daily maintenance content, the
following maintenance content should be added after the
diesel runs for 100h or the vehicle travels for
4000~5000km:

(1) Check the battery electrolyte specific gravity (see Fig.
2-8-5) or battery voltage (see Fig. 2-8-6).

(2) Check the appearances (wear conditions) of timing
belt and generator belt.

(3) clean the air cleaner,
(4) Check if diesel engine is fastened.

2.3 Second Level Technical Maintenance

It includes the first level technical maintenance contents.
The following maintenance contents should be added
after the diesel engine runs for 250 h or the vehicle
travels for 10000 ~ 12500 km(for new engines or the
second level maintenance for the first time after
overhauling in the third level maintenance, the
maintenance time should be advanced to 100 h or 4000
~ 5000 km).

(1) Replace the engine oil.
(2) Replace filter cores of the fuel filter, oil filter and air

cleaner.
(3) Inspect the dripping condition of the water pump

overflow, replace the water pump if serious dripping is
found.

(4) Inspect if the connectors of the electrical equipment

turbocharger

Rubber ball

Rubber pipe

Gravimeter
Glass tube

Storage
battery

Electrolyte

Voltmeter

Electric resistance

Discharge tongs

contact pin

Storage

battery

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

39

and wirings are firmly connected, replace them if any
blowout found.

(5) Wash the incrustation in the pipe of cooling system
and radiator.

(6) Wash the vent system of crankcase.

Fig. 2-8-7 Checking the cylinder head gasket

Fig. 2-8-8 Checking the air intake manifold

pipe gasket

Fig. 2-8-9 Checking the exhaust manifold

pipe gasket

2.4 Third Level Technical Maintenance

Under the normal circumstance, in addition to the second
level technical maintenance, replace the timing belt,
inspect the transitional wheel and tension wheel and
clean the cooling system of the complete machine after
the diesel engine runs for 1000 h or the vehicle travels
for 50000 ~ 100000 km (normally per 80000
km).According to the operating condition of the diesel
engine, the following maintenance items should be
carried out if necessary:

(1) Unpick and wash the diesel engine, remove carbon
deposit, oil dirt and incrustation, and wash all lubricating
oil pipes and oil tubes.

(2) Check the wear conditions of the valves, hydraulic
adjuster and contact face of rocker arm, repair or replace
them if necessary.

(3) Check the wear conditions of the piston ring, cylinder,
connecting rod small end bushing and connecting rod
bearing shell, replace them if necessary.

(4) Check the wear conditions of the main shaft bearing
shell and thrust plate.

(5) Check the cam driving mechanism, the sealing
condition of the camshaft front oil seal and the axial
clearance of camshaft, and the transitional wheel
subassembly and tension wheel subassembly.

(6) Check the wear condition of the intake/exhaust
valves and their valve seats, repair and grind the parts,
and check leakage of the parts, replace them if
necessary.

(7) Check the oil pump, overhaul or measure the
vulnerable parts, and adjust them.

(8) Check the cylinder head gasket and intake/exhaust
manifold pipe gasket (see Fig. 2-8-7, Fig. 2-8-8 and Fig.
2-8-9), the damaged or faulty gasket should be replaced.

(9) Check the generator and starter (see Fig. 2-8-10),
wash various parts and bearings, fill them with new
grease after they are dried, check the wear condition of
the starter gear and check if the driving device is flexible.

2.5 Seasonal Technical Maintenance

(1) It is recommended to replace the antifreeze/antirust
fluid in the diesel engine cooling system as the winter is
coming, see Fig. 2-8-11.

Cylinder head

gasket

Cylinder body

Cylinder head

Mounting
assembly

Air intake manifold

pipe gasket

Air intake

manifold pipe

Cylinder head

Mounting assembly

Air intake

manifold

pipe gasket

Air intake

manifold pipe

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Great Wall Baoding Internal Combustion Engine
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Fig. 2-8-10 Checking the generator and

starter

(2) In winter, a suitable fuel (vehicle diesel) grade should
be chosen according to the ambient temperature.

(3) In winter, the lubricating oil for winter use in the
lubricating system should be used.

(4) The concentration of battery electrolyte should be
changed in accordance with the season.

3. Technical Maintenance for Air cleaner

The function of air cleaner is to filter the dust and other
impurities in the air so as to avoid abrasion wear on the
cylinder hole, piston ring, valve and valve seat.
Therefore, the air cleaner should have a high efficiency.
The GW4D20／GW4D20B turbocharged diesel engines
are not allowed to operate without an air cleaner,
because this will easily damage the airflow sensor. The
diesel engine cannot operate properly when the airflow
sensor is damaged.

The GW4D20／GW4D20B turbocharged diesel engines
may be mounted with the oil bath air cleaners which are
equipped with inertial steel wool filter cores or the paper
filter core air cleaners. The diesel engine for vehicle isn't
equipped with the air cleaner when delivery, it will be
equipped by the vehicle manufacturer, and the airflow of
the selected air cleaner should be no less than 450 m3/h.

Fig. 2-8-11 Seasonal technical maintenance

for diesel engine

It is very important to maintain the air cleaner on
schedule, if you don’t do this, the air cleaner will be
blocked by dust and the air intake resistance will be
increased, which will cause smoking when the diesel
engine is operating, power decrease and early wear of
the engine. The user is required to maintain the air
cleaner regularly in strict accordance with the vehicle
application and maintenance instruction.

3.1 Maintenance for Oil Bath Air Cleaner

Generally, a diesel engine vehicle which is equipped with
the inertial steel wool filter core air cleaner should be
washed per 4000 ~ 5000 km of traveling distance, and
the distance may be changed upon the density of dust in
the environment. Take out the steel wool and put it in the
degreaser or parts cleaner to wash it, dry it by using
compressed air after washing. Meanwhile, clean the oil
bath of air cleaner, fill a proper amount of new oil in the
oil bath.

Attention: Use professional greaser or parts cleaner

but not petrol when washing the parts,.

3.2 Maintenance for Paper Core Air Cleaner

Generally, for the vehicle equipped with a diesel engine,
the dust in the housing of air cleaner should be removed

Generator

Generator

oil

Anti-freeze/an
ti-rust fluid

Storage battery

diesel

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

41

Fig. 2-8-12 Air cleaner (for reference only)

Fig. 2-8-13 Cleaning the air cleaner filter

core

and the filter core should be cleaned per 4000 ~ 5000 km
of traveling distance.

(1) Cleaning of the air cleaner housing and cover: Wipe
away the dust inside the housing, on the cover and on
the surface of air cleaner when maintaining and
replacing the filter core of air cleaner.

(2) Cleaning of the filter core: when the filter core is
polluted by dust and is in a dry condition, the
compressed air may be used to clean the dust. Blow the
filter core from the inner side to remove the dust by use
of the compressed air. The pressure of the compressed
air should be less than 490 kPa.

Caution: Do not blow the filter core from the outer
side, or else the dust will enter the inner side of filter core
(clean face).

The filter core should be replaced with a new one in
following cases.

——The filter core is polluted by carbon deposit or
grease.

——The filter core is seriously contaminated and the
contamination is hard to remove.

——The filter core is deformed and damaged.

Caution:
(1) The paper filter core is not allowed to be washed with

oil or fresh water, or else the filter core will be easily
contaminated by dust, and this will cause insufficient air
intake; as a result, power loss and black smoke in
exhaust may result.

(2) The tightness at the joint between the air intake pipe
and the air cleaner must be checked regularly, the
packing and the connecting pieces for tightening should
be replaced if a leakage is found to avoid abnormal wear
of the diesel engine.

4. Technical Maintenance for Oil Supply
System

4.1. Technical Maintenance for Fuel Filter

The function of fuel filter is to filter the impurities in diesel
so as to prevent precision accessories in oil supply
system from wear.

Air cleaner cover

Filter core

Air cleaner housing

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Fig. 2-8-14 Integral fuel filter

(for matching with Delphi electronic fuel

injection system)

Fig. 2-8-15 Rotary fuel filter

(for Bosch electronic fuel injection system)

Figure 2-8-16 Water level alarm lamp of

fuel-water separator

The fuel filter is mounted on the low pressure fuel circuit.
The diesel enters the filter and the mechanical impurities
are eliminated by the filter core. The filtered diesel enters
the fuel delivery pump of high pressure fuel pump via the
fuel outlet pipe.

The GW4D20／GW4D20B turbocharged diesel engines
adopt integral fuel filters (see 2-8-14) and rotary fuel
filters ( see Fig. 2-8-15) respectively, these filters are
used for DELPHI and BOSCH electric fuel injection
systems respectively. Normally, the fuel filter which is
used for the DELPHI electronic fuel injection system
should be replaced after the engine runs for 500 h or the
vehicle travels 20000 ~ 25000 km, while the filter used
for the BOSCH electronic fuel injection system should be
replaced after the engine runs for 200 h or the vehicle
travels 8000 ~ 10000 km.

If poor quality diesel is used in the diesel engine or fuel is
contaminated by impurities, it is recommended that the
time to replace the filter core should be advanced,
because the filter will be blocked soon.

After the integral fuel filter has been replaced, press the
hand fuel pump mounted on the chassis to remove the
air in the fuel circuit.

After the rotary fuel filter has been replaced, press the
manual fuel delivery pump to remove the air in the fuel
circuit.

Caution:
(1) The fuel filter is disposable and is not allowed to be

reused.
(2) The fuel filter should be replaced regularly in

accordance with the technical maintenance
requirements.

4.2 Drain of Fuel Supply System

Take the diesel engine for vehicle as an example.
When the water level in the fuel-water separator reaches

the hazard level, the alarm lamp of fuel water separator
will light up (on the instrument panel, as shown in Fig.
2-8-16).

Attention: When the diesel engine is running, the
lighting of the water level alarm lamp means that the
water in the fuel-water separator needs to be drained
out.

Method to drain the fuel filter:
(1) Park the vehicle in a safe and flat location.
(2) Open the engine hood, place the container (volume:

Cleaning of the air
cleaner filter core

Fuel outlet

Fuel return

port

Fuel inlet

Drain screw plug

Water leakage

sensor

Hand fuel
pump

Fuel return
pipe
connector

Fuel inlet pipe

Filter core of
filter cartridge

Electric
connector

Drain plug

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

43

Fig. 2-8-17 Fuel filter

about 0.2 L) to the end of vinyl hose under the fuel-water
separator drain plug.

(3) For the rotary fuel filter，anticlockwise unscrew the
drain plug (about 5 circles).Press the hand fuel pump
about 10 times till the fuel filter is filled with fuel. For the
integral fuel filter, anticlockwise unscrew the drain plug,
press the hand fuel pump mounted on the chassis till the
fuel filter is filled with fuel.

(4) After the water is drained, press the manual fuel
delivery pump or the hand fuel pump several times.

(5) Start the engine, confirm the drain plug is tight and
check if the indicator lamp of the fuel water separator is
out.

Attention: If there is water need to be drained
frequently, it means the fuel used is undesirable. If there
is water in the fuel tank, it should be drained in the
service station.

Figure 2-8-18 Selecting lubricating oil

(engine oil) in accordance with the ambient

temperature

Figure 2-8-19 Checking the oil level with an

oil dipstick

5. Technical Maintenance for Fuel Lubrication
System

5.1 Selection of Lubricating Oil

Lubricating oil (engine oil, see Fig. 2-8-18) for the diesel
engine lubrication system should be selected upon the
ambient temperature.

Caution: different grades of oil should not be mixed.

5.2 Measuring of the Oil Level

Engine oil is a consumable which ensures the diesel
engine to operate formally, therefore, the oil level should
be checked regularly. For example, check the oil level
when adding fuel or before a long journey.

The oil consumption depends on the driving condition,
weather and traveling condition. The oil consumption
rate may reach 1 L/1000 km, and the oil consumption
rate of the new diesel engine may be higher.

When checking the oil level, make sure that the diesel
engine has been preheated and the vehicle is parked on
a flat floor, stop the engine and wait for 3 minutes. Then
check the oil level.

Measure the oil level in the oil pan with the dipstick
mounted on the left side of diesel engine (see Fig.
2-8-19), draw out the dipstick and wipe away the oil on
the dipstick with a piece of cleaning cotton cloth, then
insert it into the oil pan till to its end, draw it out again to
check the oil level.

There are upper/lower scale marks on the dipstick to
help to check the oil level (see Fig. 2-8-20), the oil level

Drain
plug

Hand fuel

pump

Fuel return

pipe

connector

Fuel inlet pipe

Filter core of

filter cartridge

Electric

connector

tighten
unscrew

It is recommended to use the APICI-4

or above diesel engine oil produced by

Mobil Oil Corp.

Ambient temperature for

operation of diesel engine

Engine oil

dipstick

assembly

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Figure 2-8-20 Checking the oil level with an

engine oil dipstick

should not be below the lower scale mark, because it will
result in that the oil pump cannot pump up the oil. It is
also not appropriate that the oil level is higher than the
upper scale mark, because the crank of crankshaft will
strike on the surface of oil, which will cause malfunctions
such as oil consumption increase, exhaust deterioration,
serious carbon deposit on the piston top and the
combustion chamber walls, and piston ring stuck due to
coking, etc. Therefore, in addition to the oil pressure, the
oil level also should be checked with the dipstick before
traveling and per 300 ~ 500 km of traveling distance.

Attention: In addition to checking the oil pressure,

the oil level also needs to be checked before traveling.

5.3 Replacement with New Oil

After the oil is used for a long time, there are not only
impurities and dust, but also unburned fuel which makes
the oil thinner. Some exhaust gas enters and brings
anhydride which deteriorates the oil and then corrodes
the parts; therefore, after the oil has been used for some
time (e.g. after the vehicle traveling distance
accumulates to 8000 ~ 10000 km), the oil should be
overall replaced.

Method to replace the engine oil:
(1) Place the diesel engine or park the vehicle in a flat

location.
(2) Run the diesel engine, and stop it when the oil

temperature reaches 80 ℃.

Fig. 2-8-21 Screwing the oil drain screw plug

and draining out the engine oil

(3) Place an oil collection pan under the engine, unscrew
the oil drain screw plug (see Fig. 2-8-12), drain out the oil
in the oil pan.

Warning: Take care of hot oil so as to avoid burning,
and dispose the used oil properly to protect the
environment.

(4) Place a new sealing ring, screw the oil drain screw
plug and tighten it according to requirements, add new
engine oil and check the oil level with the dipstick.

Tightening torque for oil drain screw plug

40 N·m ± 5 N·m

If a large number of impurities deposit in the oil pan, the
lubrication system should be washed with 5# and 7#
machinery oil (light spindle oil) when the new engine is
running in, petrol or kerosene is not allowed.

When cleaning the inner side of diesel engine, fill the oil
pan with 5# or 7# machinery oil, the oil level should be at
the center of lower and upper scale marks on the

Engine oil
dipstick

Upper scale
mark

Lower scale
mark

Engine oil
dipstick guide

Oil

collection

Copper
washer

Oil drain
screw plug

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

45

Fig. 2-8-22 Filling oil through the oil filler on

the valve shield

Fig. 2-8-23 Replacing the oil filter

dipstick; remove all oil injectors and rotate the crank of
diesel engine for 2 ~ 3 minutes, then drain out the
washing oil quickly.

Each time after replacing the oil, the diesel engine should
operate without any load for a while to ensure the
lubrication system and locations required to be lubricated
can obtain adequate oil.

When filling oil through the oil filler on the valve shield
(see Fig. 2-8-22), the oil filler should be cleaned to
prevent from impurities and dust.

After the filling, close the filler cap.

Attention: The filled oil can flow into the oil pan only
through the push rod hole on the cylinder cover and the
hole on the tappet side of cylinder body, checking for the
oil level can only be carried out 5 min later.

5.4. Technical Maintenance for Oil Filter

The oil filter should be replaced after the new vehicle
travels for 2500 km; afterward, the oil and the oil filter
assembly should be replaced at the same time per 8000
~ 10000 km of traveling distance.

Method to replace the engine oil filter and precautions:
(1) Place a container under the oil filter to collect the

lubricating oil overflown.
(2) Use a special spanner to dismount the oil filter

assembly in the anticlockwise direction, see Fig. 2-8-24.

Oil filter spanner: 5-8840-0020-0.

(3) Check and clean the oil filter seat to ensure good
fitting of the new oil filter.

(4) When mounting the oil filter, apply a thin layer of oil
on the O-ring (see Fig. 2-8-25), screw the new oil filter
assembly on the engine oil cooler seat by hand until a
resistance is created, then use a spanner to tighten the
oil filter for 3/4 ~ 1 circle in the clockwise direction.

APICI-4 lubricating oil from Mobil Oil Corp.

(5) Do not start the engine before there is enough
lubricating oil in the oil pan.

(6) Start the diesel engine after the mounting, and check
if the oil filter leaks. Then stop the diesel engine, check
the lubricating oil level with a dipstick, add lubricating oil
if necessary.

oil filler cap

oil filler cap sealing ring

Cylinder body

Oil filter

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Fig. 2-8-24 Removing and reinstalling the oil

filter

Fig. 2-8-25 Installing the oil filter

Fig. 2-8-26 Low oil pressure indicator lamp

Caution:
(1) The rotary oil filter is disposable and is not allowed to

be reused.
(2) The oil filter should be replaced regularly in

accordance with the technical maintenance
requirements.

Special attention should be paid to the rubber sealing
ring when the oil filter is removed and reinstalled so as
not to damage the sealing ring and cause leakage.

If the rubber sealing ring of oil filter is damaged, it should
be replaced.

5.5 Low Oil Pressure Indicator Lamp

The low oil pressure indicator lamp of vehicle diesel
engine (see Fig. 2-8-26) will light up when the ignition

switch is in the ―ON‖ position and go out after the diesel

engine is started, and it always be off while the diesel
engine is running. If the indicator lamp flashes or keeps
on, it means that the oil pressure is low or there is no oil
pressure. In this case, the diesel engine may be
seriously damaged and it must be repaired immediately.

Attention: The diesel engine running in the low
engine oil pressure condition may cause serious
mechanical damage.

(1) When the low oil pressure indicator lamp flashes or
keeps on, park the vehicle in a safe place and stop the
engine.

(2) Let the vehicle rest for several minutes. Open the
engine hood and check the oil level.

(3) Add oil to make the oil level back to the upper scale
mark on the dipstick if necessary.

(4) Start the diesel engine and observe the low oil
temperature indicator lamp, stop the diesel engine if the
lamp does not go out within 10 s. At this moment, the
diesel engine has mechanical malfunctions and it should
be repaired.

6. Technical Maintenance for Cooling System

6.1 When the diesel engine is running, there must be
enough antifreeze and antirust fluid (coolant) to ensure
the diesel engine can run properly. Check the coolant
level every time before traveling, and replenish
antifreeze and antirust fluid in time. See Fig. 2-8-27

If the coolant level in the fluid reservoir is at or lower than
the lower limit (MIN) mark, add coolant and make the
coolant level back to the upper limit (MAX) mark. Then
close the fluid reservoir lid, and check if there is leakage.
If the fluid reservoir is empty, it is required to check the
level of the coolant in the radiator.

Special tool

Remove and reinstall

the engine oil filter

Chapter II Technical Information of Engine

Great Wall Baoding Internal Combustion Engine
Manufacturing Company Limited

47

Fig. 2-8-2 Checking the coolant level（for

reference only）

Warning: Opening the radiator cover when the
diesel engine has not been cooled completely may
cause spraying of coolant and cause serious scalding.
The engine and the radiator must be cooled before the
radiator cover is opened.

Fill coolant into the radiator (see Fig. 2-8-28):
(1) Make sure that both the engine and the radiator are

cooled.
(2) Press the radiator cover and rotate it in the

anticlockwise direction, the radiator cover can be
removed.

Fig. 2-8-28 Radiator (for reference only)

Fig. 2-8-29 Checking the radiator fan

assembly

(3) The coolant level should reach the bottom of filler
neck. If the coolant is not enough, add coolant.

(4) Add coolant slowly to avoid coolant overflowing.
Remove all the overflown coolant if the coolant
overflows.

(5) Close the radiator cover and tighten it.

6.2 Check the stopping or working conditions of the
radiator at a low temperature ( lower than 90℃) and at a
high temperature (higher than 90℃), send it for repair if
any problem is found. See Fig. 2-8-29.

6.3 Generally, the service life of the long-acting
antifreeze and antirust fluid is 1 ~ 2 years, the fluid
should be replaced when expired. When replacing the
antifreeze and antirust fluid, run the diesel engine for 5
minutes after adding new fluid to make the system fill
with the new fluid; stop the diesel engine and check the
fluid level, add fluid if not enough.

Attention:

(1) Unprocessed hard water such as tap water, mineral
water is not allowed for use.

(2) Poor quality antifreeze and antirust fluid or mixture of
different grades of antifreeze and antirust fluid is not
allowed for use in order to prevent from corrosion.

(3) If the antifreeze and antirust fluid loses, firstly, check
if the density of the antifreeze and antirust fluid
increases; if it does not, the loss is caused by leakage,
then eliminate the leakage and add the same grade of
antifreeze and antirust fluid in; if it increases, the loss is
caused by water evaporation, add distilled water in. After
adding distilled water or concentrated solution in and
mixing it evenly, check the density of the antifreeze and
antirust fluid again until it reaches the value
corresponding to the freezing point required. Send it to a
professional service station for check and maintenance
in time if users do not have required conditions.

Fluid

reservoir

Radiator

cover

Radiator

Water drain

plug

Fan assembly

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Replace the oil filter

A, B, C, D, E

Per 5000 km or per 6 months

(accumulative working time: 100 h)

Replace the air

cleaner filter core

E, F

Per 5000 km or per 6 months

(accumulative working time: 100 h)

7. Additional Maintenance in Severe Driving Conditions

If your vehicle is driven in one or more of the following conditions, the distance/time for replacing the
engine oil, oil filter and air cleaner should be shortened. Maintenance for other parts is carried out in
accordance with the maintenance items in the typical driving conditions.

Severe Conditions:
A: The traveling distance is less than 8 km every time or less than 16 km at a temperature lower than the

freezing point.
B: Drive the vehicle in a hot ( higher than 35 ℃) condition.
C: The vehicle continuously travels at the idle speed or intermittently ( stop-and-go) travels for a long

time.
D: The vehicle tows a trailer, or travels with luggage on the roof rack, or travels on a mountainous road.
E: The vehicle travels on a muddy, dusty or frozen road.
F: The vehicle travels more than 20000 km every year, or often travels at a high speed.

8. Technical Maintenance During Storage

If the storage period is less than 1 month, only technical maintenance is required to be carried out in
accordance with the accumulative working time and traveling distance, special protection procedures are
not required.

If the diesel engine has been stored for more than 1 months, special sealing storage technical
maintenance must be carried out carefully.

9. Precautions in Technical Maintenance

(1) Users need to abide by the technical maintenance regulations and maintain the diesel engine
according to the maintenance level, item and quality. Especially when the user is busy, the maintenance
items are no allowed to be reduced and the maintenance cycle is not allowed to be prolonged.

(2) The third level maintenance should be carried out indoors in order to prevent from dust.
(3) For some complex maintenances or adjustments with higher technology requirements, send them to

the professionals or Great Wall Baoding Combustion Engine Manufacturing Company.

Section IX Repair Process for Diesel Engine

1. Repair Process for Diesel Engine

The repair process is comprised of a series of steps, as shown in Fig. 2-9-1.

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Qualified (available)
spare parts

Engine handover and

exterior cleaning

Removing

Assembly components

spare parts

Washing of spare parts

Identification of spare parts

Parts need to be repaired

Repair and check for spare

parts

Combination

Check and identification

before assembling

Assembling and testing

spare parts components

assembly

Engine assembly

Engine test run

Delivery handover

Scrapped parts

Waste

warehouse

Fig. 2-9-1 Steps of repair process for the engine

2. Engine Handover and Repair Class Identification

2.1 Engine handover for repair

Before sending for repair, the user needs to thoroughly identify the technical conditions of the engine
(vehicle) according to the service condition, relative technical records (vehicle files, etc.) and results of
inspection under the condition of non-removing parts so as to make sure whether the engine (vehicle)
needs to be repaired,. When the vehicle is handed over, the owner and the staff from the service station
work together to check the engine and to define the repair class. Information about the engine
completeness and the general technical conditions should be filled in the handover sheet.

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Fig. 2-9-2 Removing the parts on the

cylinder

Fig. 2-9-3 Removing the electrical parts

Fig. 2-9-4 Washing the diesel engine

2.2 Engine repair class

The engine (vehicle) repair class is divided into overhaul,
minor repair, maintenance and adjustment.

2.2.1 Overhaul
The overhaul is the regular repair. During the overhaul,

thoroughly check the engine (vehicle), and repair or
replace the parts which are overly worn. The
performance of the engine which has gone through an
overhaul should be equal or close to that of a new
engine.

The overhaul should be carried out when the wear of the
major parts reaches or is close to its limit; generally, you
can make a repair plan according to the repair interval
(e.g. the accumulative driving distance or the
accumulative fuel consumption of the engine), but
whether to repair depends on the technical condition
determined according to inspection.

2.2.2 Minor repair
The minor repair is balancing repair (or local repair),

mainly aiming to the components or parts which are easy
to wear. In order to balance uneven wear between parts
of the engine, one or two minor repairs between two
overhauls can ensure the engine to work properly within
an overhaul cycle.

The minor repair is also required to be carried out
according to the repair interval (e.g. the accumulative
driving distance or the accumulative fuel consumption of
the engine). But whether to repair mainly depends on the
engine's technical condition.

The minor repair mainly aims at troubleshooting the
engine, local inspection, adjustment and repair, and
replacing the wearing parts.

2.2.3 Maintenance
The maintenance refers to replacing the worn parts in

order to remove the malfunctions and local damage
caused during the use of engine. Different from the minor
repair, the maintenance only aims at troubleshooting,
keeping relevant parts or the assembly working properly,
there is no need to recover the technical performance
index of a certain part or the assembly.

2.2.4 Adjustment
The adjustment refers to readjusting the worn or

disordered parts in order to remove malfunctions caused

during the use of engine. Generally, there isn’t much

removing work on the engine.

3. Exterior Washing for the Engine

After reception of the engine, move it to the location for

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exterior washing (in a cold season, first move it to a
warm room for a day to melt the frozen fouling) and then
wash it.

3.1 Drain out the lubricating oil (oil pan) and replace it
with diesel to wash, then drain out the diesel.

3.2 Drain out the fuel and coolant.

3.3 Remove the electric devices such as the generator
and starter, the parts of turbocharger and electric control
system. See Fig. 2-9-2 and Fig. 2-9-3.

3.4 Wash the exterior of diesel engine. See Fig.
2-9-4.Spray pressured water with a hose to wash the
engine exterior, to do this, use a centrifugal water pump
or plunger water pump and a water gun; the pressure of
water flow should be 147 ~ 216 kPa. This washing
process has a high quality, high efficiency and low water
consumption. It is recommended to recollect the washing
water and reuse it for the purpose of environment
protection and water conservation.

Fig. 2-10-1 Assembling according to

technical requirement

1. General Technical Requirements for
Assembling

Assembling is to connect the engine parts in accordance
with technical requirements, keep the parts in the correct
positions and connecting relationship.

1.1 The spare parts assembled should be those
manufactured according to the drawings and technical

conditions of GW4D20／GW4D20B turbocharged diesel
engines approved by our company, and their materials,
metallurgical structures, performances, geometrical
shapes, dimensions, positions, fitting, tightening torque,
sealing, and reliability should comply with the
requirements.

1.2 The spare parts assembled must be tested by the
quality control department.

―Caution‖: The spare parts must be checked

seriously before assembled, do not assemble unqualified
parts to avoid wasting time.

1.3 The parts must be washed and the edge or burr must
be removed before the parts are assembled; the
cleanness of the part should comply with relevant
technical documents.

1.4 The assembling location, instruments, tooling and
measuring apparatus should be cleaned; the staff getting

Repair the abnormal

parts immediately

Oil

Section X Technical Requirements for Engine Removal and

Reinstallation

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Fig. 2-10-2 Tightening sequence for the

fasteners

Fig. 2-10-3 Torque spanner

into the assembling location should be clean in order to
maximally reduce impurities and dust brought into the
location.

1.5 The assembling sequence should comply with the
flow process and abide by the rule of ―from interior to

exterior‖ and ―from parts to assemblies‖(parts→

components→assemblies→complete machine).

1.6 In order to improve the assembling efficiency, parts
should not be assembled on the assembling line if it can
be assembled on the component.

1.7 Combination of the spare parts should strictly comply
with relative technical documents. The combination of
the spare parts which are classified by size or quality
should strictly comply with provisions.

1.8 All parts subjected to static balance test and dynamic
balance test should be balanced, or else they are not
allowed to be installed.

1.9 Fasteners should be tightened in accordance with
tightening specifications. The fastener tightened with
plastic zone tightening angle process should not be
reused to ensure reliable connection of the connectors.
Generally, the tightening sequence should be from
center to two ends and from interior to exterior; the parts
should be tightened diagonally. The tightening torque for
fasteners of diesel engine are listed in Table 2-6-1, Table
2-6-2, and the fastener should be tightened as the
sequence showed in Fig. 2-10-2.In order to avoid
missing tightening, important fasteners which have been
tightened should be marked.

―Caution‖: Tightening torque for the fastener should
strictly comply with relative specifications, and use the
torque spanner strictly according to technical
requirements (see Fig. 2-10-3).

Fig. 2-10-4 Applying a proper amount of

lubricating oil to fasteners

1.10 When assembling, fill or apply API CI-4 engine oil
on the friction surfaces of dynamic matching parts (see
Table 2-6-7)The thread engagement of fasteners should
be lubricated with a proper amount of oil. See Fig.
2-10-4.

1.11 Water/air tight junction surfaces should be clean.
Damage, oil dirt and dust which affect tightness are not
allowed. Apply sealant in accordance with requirements
(see Table 2-6-8). Apply a proper amount of lubricating
oil to oil groove at the lip of oil seal assembly, and
assemble it with guide tools. It is not allowed to damage
the lip in order to ensure tightness.

1.12 The assembling position, sequence and matching of
the parts should be correct; interference, missing
assembling and wrong assembling are not allowed.

Indicating type torque spanner

Scale indicating type torque spanner

Lubricate it with engine oil.

Front end

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Fig. 2-10-5 Understanding the structure of

the diesel engine

Fig. 2-10-6 Using special tools

Fig. 2-10-7 Marking the parts with positional,

optional, directional and matching

requirements

1.13 The moving parts should be flexible without seizure
and bumping.

1.14 The spare parts should be handled gently during
assembling; bumping and scratching are not allowed.
For the electric control sensor, actuator and fuel injector,
dropping, pressing and wetting are not allowed.

2. General Technical Requirements for
Removal

2.1 The removal is the first step for the repair work. The
purpose is to check and repair damaged parts.

First, make clear the structures and characteristics of
GW4D20／GW4D20B turbocharged diesel engines, and
make clear the removing procedure and method to avoid
damage of spare parts. See Fig. 2-10-5.

2.2 The removal should be carried out in a proper
sequence. Generally, the rules for removal include from
the complete machine to assemblies, from assemblies to
components, from components to parts, from
accessories to main parts and from exterior to interior.

―Caution‖: In order to remove correctly and

efficiently, it is necessary to make clear the structure of
the GW4D20／GW4D20B turbocharged diesel engine
first.

2.3 For the parts whose technical conditions are normal
and can be judged without removal, it is unnecessary to
remove them. But for the parts whose technical
conditions are hard to define without removal, it is
necessary to remove them for further examination and
repair.

2.4 Appropriate tools should be selected when the parts
are removed in accordance with their structures. Fierce
knock is not allowed to avoid damage and deformation of
the parts. In order to improve efficiency, use special
tools. See Fig. 2-10-6. When the bolts and nuts are
removed, the proper sized fixed spanner should be
selected, it is not recommended to use the adjustable
spanner or randomly extend the torque for the spanner.

2.5 For the parts which have positional, optional and
directional requirements such as main shaft bearing
shells, valves, pistons and connecting rods, etc., in order
to improve the assembling efficiency and ensure correct
assembling, they should be marked on the non-working
face in accordance with specific conditions.

2.6 The parts removed should not be left about or piled
up, they should be classified and stored in accordance
with their materials, sizes, shapes and precisions so as
to avoid damage or missing and facilitate the next
process.

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Tool and Instrument Name

Tool and Instrument

Code

Remarks

Crankshaft timing pulley
puller

5-8840-2035-0

Crankshaft timing pulley
installer

5-8522-0024-0
Valve spring compressor

9-8523-1423-0(J-29760)

See Page 106, 122, 127, 218

Valve oil seal remover

5-8840-0373-0

See Page 122, 219

Valve oil seal installer

5-8840-2033-0

See Page 106, 126, 219

Piston ring compressor

5-8840-9018-0

See Page 136,150,166,257,276,290

Tachometer

5-8840-2093-0

Valve guide replacer

5-8523-1212-0

Camshaft timing pulley puller

5-8840-0086-0

Rubber hardness tester

5-8840-0199-0

Compressed pressure gauge

5-8840-2008-0(J-27762)

Pressure gauge connector

5-8531-7002-0

Measuring device

5-8840-0145-0

Oil filter spanner

5-8840-0020-0

See Page 163, 168, 238, 239

Goniometer

5-8840-0266-0

Oil injector tester

5-8840-9016-0

Oil injector body remover

5-8840-2034-0

Bearing replacer

5-8840-2038-0

Radiator water inlet cover
tester

5-8840-2036-0

See Page 48, 329, 330

Section XI Special Tools and Instruments for Repair

When adjusting, testing, maintaining, repairing, removing, assembling the diesel engine, you may use
special tools, instruments and devices in order to conveniently and quickly remove and reinstall the
spare parts, examine the spare parts and define malfunctions,. This will not only avoid damage, but also
ensure service quality.

Table 2-11-1 Special tools and instruments for repair

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Tool and Instrument Name

Tool and Instrument

Code

Remarks

Oil filter spanner

5-8840-0253-0(J-22700)

See Page 47, 308, 309

Front oil seal remover

5-8840-2362-0

See Page 130,158,163,264,273,286, 336

Front oil seal installer

5-8840-2361-0

See Page 166, 245, 290, 336

Rear oil seal remover

5-8840-2360-0

See Page 131,164,268,274,287

Rear oil seal installer

5-8840-2539-0

See Page 135, 268, 275, 289

Slide hammer

5-8840-0019-0

See Page 241

Transmission first shaft front
bearing remover

5-8840-2000-0

See Page 241

Transmission second shaft
front bearing remover

5-8522-0024-0

See Page 242

Guide centering device

5-5825-3001-0

See Page 242, 268, 269, 286

Fuel injection system
measuring device

0-986-613-100

Oil return amount measuring
device

0-986-612-900

KTS 650 diagnostic
apparatus

0-986-612-901

See Page 86

The special tools listed in this manual are for reference only; users may purchase appropriate special
tools in accordance with maintenance requirements.

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Fig.2-12-1 GW4D20 turbocharged diesel

engine assembly

Fig.2-12-2 Cleaning the filter core of air

cleaner

Fig.2-12-3 Washing the air cleaner cover

and housing

Attention: The general repair operation should be
done by qualified maintenance personnel.

1. Model Mark

Engine number

The diesel engine number is printed on the central front
of left side of cylinder body, as shown in Fig.2-12-1.

Example of the engine number printed on cylinder body:

2. Air Cleaner

Dry paper filter core

Cleaning methods may differ according to filter core
conditions.

Filter core blocked by dust

Move the filter core with hands and blow the filter core
from the inner side to the outer side with compressed air,
the dust will be removed by doing this. See Fig.2-12-2.

Caution: Do not blow the filter core from the outer
side to the inner side with compressed air; if so, the dust
will enter the interior of filter core (clean face).

The pressure of compressed air

392 ～ 490 kPa

Caution: Do not strike the filter core on other
objects to clean the filter core, if so, the filter core will be
damaged.

If the following cases appear, the filter core should be
replaced:

——the filter core is contaminated by carbon deposit or
grease.

——the filter core is seriously contaminated, and the
contamination is hard to remove.

——the filter core is deformed and damaged.

Position of model

mark

Model number

Asterisk

Year

Month

Sequence

Asterisk

Filter core of air

cleaner

Cleaner cover

Cleaner housing

Section XII Repair Operation for Engine

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Fig.2-12-4 Maintaining the oil filter

Fig. 2-12-5 Applying a thin layer of oil to the

new filter core O-ring before assembling

Fig. 2-12-6 Removing and reinstalling the oil

filter

When replacing or cleaning filter core, clean the inside of
air cleaner housing. See Fig. 2-12-3.

Caution:

(1) The paper filter core is not allowed to be washed with
oil or fresh water, or else the filter core will be
contaminated and blocked by dust very easily, and this
will cause insufficient air intake; as a result, power loss
and black smoke in exhaust may result.

(2) The tightness at the joint between the air intake tube
and air cleaner must be checked regularly. If leakage is
found, the packing and tightening connector should be
replaced to avoid abnormal wear of the diesel engine.

3. Lubrication System

Oil filter

Caution: The oil filter is disposable and is not
allowed to be reused.

Replacing Sequence:

(1) Protect the generator with plastic cloth or paper
boards. Loosen the oil drain plug to drain out the oil.

Warning: Collect the used oil, and dispose it

properly to protect the environment.
(2) Retighten the oil drain plug after several minutes.
(3) Unscrew the used oil filter in the anticlockwise

direction with a filter spanner.
(4) Clean the matching surface of engine oil cooler, this

will make the oil filter installed properly.
(5) Apply a thin layer of oil to the O-ring. See Fig. 2-12-5.

API CI-4 lubricating oil produced by Mobil Oil

Company.
(6) Screw into the new oil filter until the filter O-ring fits

into the sealing face.
(7) Screw the filter with a filter spanner for 3／4 ~ 1 circle,

as shown in Fig. 2-12-6.

Oil filter spanner: 5-8840-0020-0.

After the assembling, there should be no leakage at

the filter sealing ring.
(8) Check the oil level in the engine lubrication system

with an engine oil dipstick (see Fig.2-12-7), add oil till it
reaches the specified level if necessary.

Cylinder body

Oil filter

Special tool

Removing and

reinstallation with

a special tool

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Fig.2-12-7 Checking the oil level in the

diesel engine

It is recommended to use APlCl-4 or above diesel engine
oil produced by Mobil Oil Corporation.

Start the diesel engine and check if the lubrication
system works properly, and check if there is leakage in
the oil filter.

Fig. 2-12-8 Fuel filter

Fig.2-12-9 Water level indicator lamp of

water-fuel separator

4. Fuel System

Fuel filter

Caution: The fuel filter is disposable and is not

allowed to be reused.
The cartridge and filter core of the fuel filter assembled on

the CW4D20／CW4D20B turbocharged diesel engine is
integral; when they are replaced, the whole filter
assembly should be replaced.

Replace the fuel filter regularly in accordance with
technical Maintenance requirements.

Replacing Sequence:
(1) Loosen the fuel filter in the anticlockwise direction with

a filter spanner.

Fuel filter spanner: 5-8840-0253-0.
(2) Clean the matching surface of the upper cover of the

fuel filter.
(3) Install a new fuel filter and tighten it until it contacts

with the sealing face.
(4) Screw it for additional 3/4 ～ 1 circle with a filter

spanner.
(5) Operate the hand fuel pump several times and check

if there is fuel leakage.

Attention: It is recommended to use the original

fuel filter produced by our company.

Water drain sequence for the fuel-water separator

When the water content in the fuel-water separator
exceeds the specified value, the indicator lamp on the
instrument panel will light up. See Fig. 2-12-9.

Drain the water and other impurities in the fuel-water

Engine oil
dipstick

Engine oil
dipstick guide
pipe

Upper scale

Lower scale

Hand fuel

pump

Oil return

hose

Oil inlet pipe

connector

Cartridge and

filter core

Electric

connector

Water drain plug

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Fig.2-12-10 Drain the water with the

fuel-water separator

Fig.2-12-11 Checking after draining water

separator in the following sequence.
(1) Park the vehicle in a secure and flat location.
(2) Open the engine hood and place a container (volume:

about 0.2 L) under the hose end of fuel-water separator.
(3) Loosen the water drain plug (about 5 circles) and

press the hand fuel pump for about 10 times to drain out
about 0.1L of water, as shown in Fig. 2-12-10.

(4) Tighten the water drain plug immediately after
draining and pressing the hand fuel pump several times,
as shown in Fig.2-12-11.

After starting the diesel engine, check if there is
water leaked from the water drain plug; meanwhile, check
if the indicator lamp of fuel-water separator has gone out.

Attention: If there is too much water in fuel, it
indicates that the fuel is not qualified. If there is water
deposit, remove it in time.

Fig. 2-12-12 Checking the coolant level in

the fluid reservoir (for reference only)

Fig. 2-12-13 Mixing ratio of coolant

5. Cooling System

5.1 Coolant level

Check the coolant level, and fill the fluid reservoir (water
tank) if necessary. If the coolant level is lower than the

―MIN‖ scale mark, check carefully if there is leakage in

the cooling system. Then add coolant until the coolant
level is between the lower limit(MIN) and the upper limit
(MAX). See Fig. 2-12-12. Close the fluid reservoir cover
after adding coolant.

Attention:
(1) Do not overfill the fluid reservoir.
(2) The radiator water filler cover can only be opened

when absolutely necessary.

Warning:
(1) Checking coolant level should be carried out when the

engine is cold.
(2) The coolant is poisonous, thus must be stored in the

original container to avoid the direct touch from human.
It is recommended to use the coolant produced by our

company. When replenishing coolant, never add any
antirust additive or other additives into the cooling

Loosen the drain plug in the

anticlockwise direction

Tighten the drain plug in the

anticlockwise direction

Fluid

reservoir

Mixing ratio(%)

Freezing point

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Fig. 2-12-14 Checking the cooling system

with a tester

Fig. 2-12-15 Checking the water filler cover

with a tester

system. Because they may be incompatible with the
coolant or engine parts.

See Fig. 2-12-13 to determine the correct mixing ratio of
coolant and water.

5.2 Check for the cooling system

Mount the radiator tester on the radiator. Apply the test
pressure to the cooling system to check leakage. See
Fig. 2-12-14.

The test pressure should not exceed the specified
pressure.

196 kPa

5.3 Check for the radiator cover

The radiator filler cover is designed to keep a 88 ~ 118
kPa pressure in the cooling system. Check if the filler
cover meets requirements with a radiator filler cover
tester. See Fig. 2-12-15.

During testing, the radiator filler cover must be replaced if
it cannot keep the specified pressure.

Design pressure of the

radiator filler cover

Pressure valve

88～118 kPa

Negative pressure valve

(reference value)

1.0 ～3.9 kPa

Radiator filler cover tester: 5-8840-2036-0.

Fig. 2-12-16 Checking the lift of thermostat

valve

5.4 Check for the thermostat mounting assembly

5.4.1 Check for the thermostat cover and thermostat
Check if the thermostat cover and thermostat are

deformed; they must be replaced if deformed.

5.4.2 Operation test for the thermostat
(1) Dip the thermostat completely in water.
(2) Heat the water and stir it to avoid direct heating to the

thermostat.
(3) Observe temperature changes through the

thermometer in the water; check the initial opening
temperature of the thermostat.

Initial opening temperature of the thermostat

76 ℃ ± 2 ℃

(4) Check the temperature when the thermostat is
completely opened. See Fig. 2-12-17.

Temperature when the thermostat is completely opened

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Fig. 2-12-17 Checking the opening

temperature of thermostat valve

Fig. 2-12-18 Checking the lift of thermostat

valve

Fig. 2-12-19 Adjusting the idling speed

88 ℃

The thermostat should be replaced if the opening
temperature of valve is not correspondent with
provisions.

(5) Check the lift when the valve is completely opened.
See Fig. 2-12-18.

Lift when the valve is completely opened

When the water temperature is at 88 ℃ >8.5 mm

If the lift of thermostat is not correspondent with

provisions, the thermostat should be replaced.
(6) Check if the valve is closed when the thermostat is at

a low temperature.
The thermostat should be replaced if the valve cannot be

closed.
(7) Check if the thermostat rubber sealing ring is aged

and deformed; the sealing ring should be replaced if it is
aged and deformed.

6. Engine Control

6.1 Check idling speed

(1) Operate the parking brake and brake the driving
wheels

(2) Place the transmission to neutral gear.
(3) Start the diesel engine and heat it.
(4) Remove the diesel engine control cable from the

control rod.
(5) Mount the tachometer on the diesel engine.

Check the idling speed of the diesel engine: if the
idling speed exceeds the specified range, it should be
adjusted in the service station authorized by our
company.

Idling speed of the diesel engine

750 r/min ± 50 r/min

The lift of valve should be at least 8.5 mm
when the water temperature is 88 ℃

Valve size

when

completely

opened

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Fig. 2-12-20 Adjusting the throttle pedal

Fig. 2-12-21 Measuring the voltage at the

glow plug end with a universal meter

6.2 Adjustment to the throttle control cable

(1) Loosen the throttle wiring bracket bolt.
(2) Check if the idling control button is located in the idling

position of diesel engine.
(3) Make sure that the throttle connecting rod is

completely closed, and then tighten the control cable to
remove looseness.

6.3 Adjustment to throttle pedal

(1) Loosen the lock nut.
(2) Adjust the height between bolt and base plate.
Adjust the height between bolt and base plate.

18 ～ 28 mm

(3) Check if the throttle pedal is 5 ～ 10mm upper the
pedal buffer. See Fig. 2-12-20.

(4) Press the throttle to its end and check if the diesel
engine operates at the highest speed and check if all
connections operate stably.

7. Quick start-up system

Checking procedure for the quick start-up system II:
(1) Place the start-up switch to the ―OFF‖ position.
If the quick start-up system II works formally, the glow

relay will give clicking sounds within 15 s after the switch
is connected.

(2) After the start-up switch is switched to the ―OFF‖
position, measure the voltage at the glow plug end with a
universal meter.

Voltage at the glow plug end

About 12 V

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Cylinder body assembly

Cylinder body assembly

Section XIII Engine Parts and Tightening Torques

1. Engine Bracket Mounting Assembly

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Cylinder body component

Sectional view of the

upper cylinder body

2. Cylinder Body Mounting Assembly

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Upper cylinder body

Crankshaft

Lower cylinder body

Step 1

Step 2

Step 3

Turn for 90°

Turn for 90° again

3. Cylinder Body Component

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DELPHI cylinder

cover assembly

BOSCH or XINFENG

cylinder cover assembly

BOSCH or XINFENG

cylinder head

4. Cylinder Head Mounting Assembly ——1

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DELPHI camshaft

bearing cap

BOSCH or XINFENG
camshaft bearing cap

Cylinder head assembly

5. Cylinder Head Mounting Assembly ——2

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Step 1

Step 2

Step 3

Step 1

Step 2

Step 3

Turn for 90° ± 5°

Turn for 120° ± 5°

Turn for 120° ± 5°

Turn for 90° ± 5°

Camshaft bearing cap

Cylinder head gasket

Cylinder head

6. Cylinder Head Mounting Assembly ——3

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Step 1

Step 2

Turn for 90° ± 5°

7. Piston Connecting Rod Mounting Assembly

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8. Crankshaft Flywheel and Clutch Mounting Assembly

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DELPHI air intake

manifold pipe

BOSCH or XINFENG air

intake manifold pipe

9. Air Intake and Exhaust Systems Mounting Assembly ——1

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Cylinder head mounting
assembly

Air intake manifold pipe

10. Air Intake and Exhaust Systems Mounting Assembly ——2

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11. Oil Pan and Engine Oil Collector Mounting Assembly

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Cylinder body assembly

Engine oil pump mounting

assembly

12. Engine Oil Pump Mounting Assembly

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Upper cylinder body

Engine oil filter mounting assembly

Engine oil cooler mounting assembly

13. Engine Oil Cooler and Cooling Pipelines Mounting Assembly

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14. Timing Mechanism Mounting Assembly ——1

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BOSCH or XINFENG
crankshaft timing belt

pulley component

DELPHI crankshaft

timing belt pulley

component

15. Timing Mechanism Mounting Assembly ——2

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Note: ① DELPHI fuel supply system mounting assembly.

16. Fuel Supply System Mounting Assembly ——1①

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Note: ① BOSCH fuel supply system mounting assembly.

17. Fuel Supply System Mounting Assembly ——2①

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Note: ① XINFENG fuel supply system
mounting assembly.

18. Fuel Supply System Mounting Assembly ——3①

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Note: ① VGT turbocharger mounting assembly.

19. Turbocharger Mounting Assembly ——1①

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Note: ① WGT turbocharger mounting assembly.

20. Turbocharger Mounting Assembly ——2①

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Air intake manifold pipe

Cylinder head

21. EGR System Mounting Assembly

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Cylinder body assembly

Crankshaft position

sensor (XINFENG)

22. Electronic Control System Sensor

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Cylinder body assembly

Generator belt

23. Generator Mounting Assembly

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Exported AT vehicle

model

Air intake manifold pipe

Common vehicle model

Air intake manifold pipe

24. Throttle Mounting Assembly

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Cylinder body assembly

Thermostat shield

Cylinder body assembly

25. Thermostat and Water Pump Mounting Assembly

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Cylinder body assembly

Cylinder body assembly

Lower cylinder body

26. Engine and Compressor Mounting Assembly

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Cylinder head assembly

Cylinder body assembly

27. Vacuum Pump and Steering Pump Mounting Assembly

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Chapter III Malfunction Diagnosis and Troubleshooting

Section I Troubleshooting

When the diesel engine works, due to wearing, distortion, usage and improper maintenance and so on,
the technical condition of each part will worsen gradually; when some technical indicators surpass the
tolerant limits, it indicates that the diesel engine is malfunctioning. When a malfunction appears, the
diesel engine may not work normally if the malfunction is not eliminated in time. In such a case, the
dynamic and economical properties of the diesel engine will degrade and the operation performance will
worsen. Moreover, the parts will be worn too early, and even accidental damage may result.

Some malfunctions such as air presence in the fuel system, air cleaner blockage, and excessive
looseness of the driving belt can be eliminated by necessary technical maintenance and adjustment.
While some malfunctions such as damage of the cylinder head gasket, serious wear of the piston ring,
valve taper face and timing belt, and excessive wear of the bearing shell can not be eliminated by
general maintenance and adjustment due to the defects in relevant mechanisms. In order to eliminate
such malfunctions, it is necessary to remove and repair the diesel engine or replace the parts involved..

Principles for malfunction diagnosis and elimination

(1) Diesel engine malfunctions are usually caused by improper operation or deficient maintenance.
When a malfunction appears, first check if the operation and maintenance regulations are carried out
seriously.

(2) Eliminate the malfunction in time. First check carefully and analyze the cause of the malfunction, do
not remove any part blindly.

(3) The diagnosis and elimination for complex malfunctions should be done by professional persons by
means of appropriate apparatus and specialized equipment. If the user can not judge or cope with the
malfunction, please contact the authorized service station of our company

(4) Only if the diesel engine is in good technical condition can it go on working; working in ―ill‖ technical

condition is not allowed. For in such condition, the parts will wear rapidly and the service life of the whole
vehicle will shorten. Even malignant accidents may be aroused.

Precautions for malfunction diagnosis and elimination.

(1) Do not start the diesel engine when the storage battery is not connected.
(2) Do not disconnect the storage battery from the internal circuits of the vehicle when the diesel engine

is running.
(3) The polarities of the storage battery and the control unit should not be matched reversely.
(4) Always start the diesel engine with the help of storage battery other than the quick start-up device.
(5) Always remove the vehicle storage battery before charging it.
(6) Remove or insert each kind of plug of the electrical control circuit only under the condition that the

storage battery is disconnected (the ignition switch is off).
(7) Diagnose the electronic control diesel engine with suitable equipment as required by the

manufacturer. The diagnostic equipment should be earthed with the cylinder body of diesel engine
during diagnosis.

(8) Do not use traditional methods to diagnose the new type of electronic control diesel engine.
(9) The diagnostic equipment and the control unit of the diesel engine should be connected properly.
(10) Anti-source diagnostics is often applied to the electronic control diesel engine system, and its

process is: first use the diagnostic equipment to find out the possible cause, and then find the exact
position from the peripheral equipment to the control unit gradually and eliminate the malfunction at last.