Doosan GL08K Manual

950106-050004EN
GL08K
GAS VEHICLE ENGINE
Operation &
Maintenance Manual

FOREWORD
This maintenance manual is designed to serve as a reference for DOOSAN Infracore (here after DOOSAN’s)
customers and distributors who wish to gain basic product knowledge on DOOSAN’s
GL08K Compressed Nat-
ural Gas engine.
This economical and high-performance compressed natural gas engine has been so designed and manufac-
tured to be used for the overland transport or industrial purpose. That meets all the requirements such as low
noise, fuel economy, high engine speed, and durability.
To maintain the engine in optimum condition and retain maximum performance for a long time, CORRECT
OPERATION and PROPER MAINTENANCE are essential.
In this manual, the following symbols are used to indicate the type of service operations to be performed.
Removal Adjustment
Installation Cleaning
Disassembly Pay close attention-Important
Reassembly Tighten to specified torque
Align the marks Use special tools of manufacturer's
Directional Indication Lubricate with oil
Inspection Lubricate with grease
Measurement
During engine maintenance, please observe following instructions to prevent environmental damage ;
Take old oil to an old oil disposal point only.
Ensure without fail that oil and coolant will not get into the sea or rivers and canals or the ground.
Treat undiluted anti-corrosion agents, antifreeze agents, filter element and cartridges as special waste.
The regulations of the relevant local authorities are to be observed for the disposal of spent coolants and
special waste.
If you have any question or recommendation in connection with this manual, please do not hesitate to contact
our head office, dealers or authorized service shops near by your location for any services.
For the last, the content of this maintenance instruction may be changed without notice for some quality
improvement. Thank you.
2018. 11.
950106-050004EN
Doosan Infracore

CONTENTS
1. Safety Regulations & Specifications ............................................................................................1
1.1. Safety Regulations ................................................................................................................................. 1
1.2. Engine Specifications ............................................................................................................................. 8
1.3. Engine Power ......................................................................................................................................... 9
1.4. Engine Performance Curve .................................................................................................................. 10
1.5. Engine Assembly ................................................................................................................................. 12
2. Technical Information ..................................................................................................................16
2.1. Engine Model and Serial Number ........................................................................................................ 16
2.2. Diagnostic Tool (SCAN-200) ................................................................................................................ 17
2.3. Engine Character ................................................................................................................................. 17
2.4. Diagnosis and Remedy ........................................................................................................................ 36
2.5. Engine Inspection ................................................................................................................................ 45
3. Maintenance..................................................................................................................................46
3.1. Engine Disassembly ............................................................................................................................ 46
3.2. Inspection and Measurement on Major Parts ...................................................................................... 61
3.3. Engine Reassembly ............................................................................................................................. 79
3.4. Major Electric Parts Replacement ...................................................................................................... 104
3.5. Electrical System ............................................................................................................................... 116
4. Commissioning and Operation .................................................................................................148
4.1. Operation Preparation ........................................................................................................................ 148
4.2. Breaking-in ......................................................................................................................................... 148
4.3. Inspections after Starting ................................................................................................................... 150
4.4. Operation in Winter Time ................................................................................................................... 150
4.5. Tuning the Engine .............................................................................................................................. 151
4.6. Maintenance and Care ....................................................................................................................... 151
4.7. Cooling System .................................................................................................................................. 153
4.8. Adjustment of Valve Clearance .......................................................................................................... 155
4.9. Ignition Timing .................................................................................................................................... 156
4.10. Tightening the Cylinder Head Bolts ................................................................................................. 157
4.11. Cylinder Compression Pressure ...................................................................................................... 157
5. Maintenance of Major Components..........................................................................................159
5.1. Cooling System .................................................................................................................................. 159
5.2. Lubricating System ............................................................................................................................ 162
5.3. Air Intake System ............................................................................................................................... 165
5.4. Turbocharger ..................................................................................................................................... 170
 Appendix
 Special Tool List

Safety Regulations & Specifications
- 1 -
1. Safety Regulations & Specifications
1.1. Safety Regulations
1.1.1. General notes
 Day-to-day use of power engines and the service products necessary for running them presents no
problems if the persons occupied with their operation, maintenance and care are given suitable
training and think as they work.
 This summary is a compilation of the most important regulations, These are broken down into main
sections which contain the information necessary for preventing injury to persons, damage to
property and pollution. In addition to these regulations those dictated by the type of engine and its
site are to be observed also.
IMPORTANT :
If despite all precautions, an accident occurs, in particular through contact with
caustic acids, fuel penetrating the skin, scalding from oil, antifreeze being splashed
in the eyes etc, consult a doctor immediately.
1.1.2. To prevent accidents with injury to persons
1) Engine starting and operation
 Before putting the engine into operation for the first time, read the operating instructions carefully
and familiarize yourself with the “critical” points. If you are unsure, ask your DOOSAN
representative or service man.
 For reason of safety we recommend you attach a notice to the door of the engine room
prohibiting the access of unauthorized persons and that you draw the attention of the operating
personal to the fact that they are responsible for the safety of person who enter the engine room.
 The engine must be started and operated only by authorized personnel.
Ensure that the engine cannot be started by unauthorized person.
 When the engine is running, do not get too close to the rotating parts.
 Do not touch the engine with bare hands when it is warm from operation risk of bums.
 Exhaust gases are toxic. If it is necessary to run an engine in an enclosed area, remove the
exhaust gases from the area with an exhaust pipe extension.

Safety Regulations & Specifications
- 2 -
2) Maintenance and care
 Always carry out maintenance work when the engine is switched off. If the engine has to be
maintained while it is running, e.g. changing the elements of change-over filters, remember that
there is a risk of scalding. Do not get too close to rotating parts.
 Change the oil when the engine is warm from operation.
CAUTION :
There is a rise of burns and scalding. Do not touch oil drain plug or oil filters with
bare hands.
 Take into account the amount of oil in the sump. Use a vessel of sufficient size to ensure that the
oil will not overflow.
 If change or refill the cooling water, disassemble the drain plug when the engine has cooled
down. Heated cooling water has the risk of scalding and safety accidents.
 Neither tighten up nor open pipes and hoses (lube oil circuit, coolant circuit and any additional
hydraulic oil circuit) during the operation. The fluids which flow out can cause injury.
 Fuel is inflammable. Do not smoke or use naked lights in its vicinity. The tank must be filled only
when the engine is switched off.
 Keep service products (anti-freeze) only in containers which can not be confused with drinks
containers.
 Comply with the manufacturer’s instructions when handling batteries.
CAUTION :
Accumulator acid is toxic and caustic. Battery gases are explosive.
Therefore it should be done by an expert of the handling professionally.
3) When carrying out checking, setting and repair work
 Checking, setting and repair work must be carried out by authorized personnel only.
 Use only tools which are in satisfactory condition. Slip caused by the worn open-end wrench
could lead to injury.
 When the engine is hanging on a crane, no-one must be allowed to stand or pass under it. Keep
lifting gear in good condition.
 When do electric weld, stop the engine, power off, then remove the wire harness’ connector
which is connected to the ECU.
 Do not weld the electric control unit (ECU) absolutely, and do not damage on it by electrical or
mechanical shock.
 When working on the electrical system disconnect the battery earth cable first. Connect it up
again last in prevent short circuits.

Safety Regulations & Specifications
- 3 -
1.1.3. To prevent damage to engine and premature wear
1) Never demand more of the engine than it was designed to yield for its intended purpose.
Detailed information on this can be found in the sales literature. Electric control unit must not be
adjusted without prior written permission of DOOSAN.
1) If faults occur, find the cause immediately and have it eliminated in order to prevent more serious of
damage.
2) Use only genuine DOOSAN spare parts. DOOSAN will accept no responsibility for damage resulting
from the installation of other parts which are supposedly “just as good”.
3) In addition to the above, note the following points.
 Never let the engine run when dry, i.e. without lube oil or coolant.
 Pay attention to cleanliness. The Diesel fuel must be free of water.
 Use only DOOSAN approved service products (engine oil, anti-freeze and anticorrosion agent)
 Refer to the subjects of recommendation of the fuel.
 Have the engine maintained at the specified intervals.
 Do not switch off the engine immediately when it is warm, but let it run without load for about 5
minutes so that temperature equalization can take place.
 Never put cold coolant into an overheated engine.
 Do not add so much engine oil that the oil level rises above the max. marking on the dipstick. Do
not exceed the maximum permissible tilt of the engine.
 Always ensure that the testing and monitoring equipment (for battery charge, oil pressure,
coolant temperature) function satisfactorily.
 Do not let the raw water pump run dry, If there is a risk of frost, drain the pump when the engine
is switched off.
1.1.4. To prevent pollution
1) Engine oil, filter elements, fuel filters
 Take old oil only to an oil collection point.
 Take strict precautions to ensure that oil does not get into the drains or into the ground. The
drinking water supply could be contaminated.
 Filter elements are classed as dangerous waste and must be treated as such.
2) Coolant
 Treat undiluted anti-corrosion agent and / or antifreeze as dangerous waste.
 When disposing of spent coolant comply with the regulations of the relevant local authorities.

Safety Regulations & Specifications
- 4 -
1.1.5. Notes on safety in handling used engine oil
Prolonged or repeated contact between the skin and any kind of engine oil decreases the skin.
Drying, irritation or inflammation of the skin may therefore occur. Used engine oil also contains
dangerous substances which have caused skin cancer in animal experiments. If the basic rules of
hygiene and health and safety at work are observed, health risks are not to the expected as a result of
handling used engine oil.
< Health precautions >
 Avoid prolonged or repeated skin contact with used engine oil.
 Protect your skin by means of suitable agents (creams etc.) or wear protective gloves.
 Clean skin which has been in contact with engine oil.
 Wash thoroughly with soap and water.
 Do not use petrol, Diesel fuel, gas oil, thinners or solvents as washing agents.
 After washing apply a fatty skin cream to the skin.
 Change oil-soaked clothing and shoes.
 Do not put oily rags into your pockets.
CAUTION :
Ensure that used engine oil is disposed of properly.
- Engine oil can endanger the water supply.
For this reason do not let engine oil get into the ground, waterways, the drains or the sewers. Violations
are punishable. Collect and dispose of used engine oil carefully. For information on collection points
please contact the seller, the supplier or the local authorities.
1.1.6. Precaution for handling NOx clean
 NOx clean is a solution diluted to the regulated ratio. Manufacturing method is standardized through
standards.
(1) As a colorless, odorless and nonpoisonous liquid, it is not dangerous from ignition or explosion.
(2) NOx clean is widely used for chemical fertilizer, cosmetics, fabric, pharmaceutical etc.
 Precaution for handling NOx clean (1)
(1) If you have swallowed NOx clean, you must immediately receive medical treatment and follow
the directions from a medical expert for vomiting etc.
(2) Avoid repeated contact and always wash your hands after handling NOx clean.
(3) For the contacted part, use soap or mild detergent to wash with plenty of water until you can
judge that the chemical substance is removed.
(4) To prevent any stimulus or eruption on skin, receive immediate medical treatment.
(5) Wash any contaminated clothes or shoes completely before reusing them.
(6) When contacted on the eye, immediately wash with plenty of water or saline solution (At least for
15 ~ 20 minutes), and receive immediate medical treatment.

Safety Regulations & Specifications
- 5 -
 Precaution for handing NOx clean (2)
(1) Collect NOx clean in an appropriate container to handle any leakage.
(2) Store NOx clean from a distant location from water supply or sewage.
(3) Prohibit access except for authorized personnel and mark the location as dangerous to limit the
access.
(4) For future handling or reuse, store the solution in a clean and dry container.
(5) Be careful not to let it flow to the water sewage.
 How to store NOx clean
(1) Store NOx clean in a completely sealed container.
(2) Store NOx clean in a dry and well ventilated location.
(3) For the storage container, do not contact or use metallic material (Zinc, copper, magnesium,
general alloy), except for stainless steel.
1.1.7. General repair instructions
1. Before performing service operation, disconnect the grounding cable from the battery for reducing
the chance of cable damage and burning due to short-circuiting.
2. Use covers for preventing the components from damage or pollution.
3. Engine oil and anti-freeze solution must be handled with reasonable care as they cause paint
damage.
4. The use of proper tools and special tools where specified is important to efficient and reliable service
operation.
5. Use genuine DOOSAN parts necessarily.
6. Used cotter pins, gaskets, O-rings, oil seals, lock washer and self-lock nuts should be discarded and
new ones should be prepared for installation as normal function of the parts can not be maintained if
these parts are reused.
7. To facilitate proper and smooth reassemble operation, keep disassembled parts neatly in groups.
Keeping fixing bolts and nut separate is very important as they vary in hardness and design
depending on position of installation.
8. Clean the parts before inspection or reassembly. Also clean oil ports, etc. using compressed air to
make certain they are free from restrictions.
9. Lubricate rotating and sliding faces of parts with oil or grease before installation.
10. When necessary, use a sealer on gaskets to prevent leakage.
11. Carefully observe all specifications for bolts and nuts torques.
12. When service operation is completed, make a final check to be sure service has been done
property.
13. Work the fuel line after the common rail pressure and engine temperature is checked with the
SCAN-200. (past about 5 minutes after engine stop)

Safety Regulations & Specifications
- 6 -
1.1.8. Handle compressed natural gas safety
Natural gas is highly flammable and explosive and may be extremely cold. The following cautions must
be taken to avoid personal injury or engine damage.
 Do not smoke when installing or servicing
the engine or fuel system.
 Installation or servicing of natural gas
equipment must only be conducted in well
ventilated, natural gas compatible areas.
Do not install or service equipment in an
enclosed area where ignition sources are
present without ensuring that an
undetected gas leak may be safely
vented without being ignited.
 Do not vent natural gas or permit leaks
inside an enclosed area.
Bleed natural gas lines before installing or
servicing any component connected to
the fuel lines.
1.1.9. Venting an operable engine to relieve
natural gas pressure
 To avoid personal injury an operable
natural gas engine must be kept in a well
ventilated area away from open flames
and sparks.
 If the engine can run, use the following
venting procedure to relive the natural gas
pressure downstream of the shutoff valve.
1) Shut off manual valves on natural gas
supply tanks and main shutoff valve
on natural gas fuel supply line.
2) Start engine and run until it stalls due to fuel starvation.
3) Check to make sure gauge pressure at point on the natural gas fuel line to be vented has been
reduced to zero. If not, repeat step 1) Then repeat step 2).
4) Disconnect vehicle batteries using switch in battery compartment or by disconnecting battery
ground cable.
5) Slightly loosen the CNG fuel line fitting to be serviced in a well ventilated area to allow any
remaining gas to vent.
6) Completely open the fitting that was slightly opened and allow to vent in a well ventilated area.
EB8O2001
EB8O2002
EB8O2003

Safety Regulations & Specifications
- 7 -
1.1.10. Avoid heating near pressurized fluid lines
 Wear welding goggles and gloves when
welding or using an acetylene torch.
 Insure a that metal shield separated the
acetylene and oxygen which must be
chained to a cart.
 Do not weld or heat areas near fuel tanks
or fuel lines.
HDO1049I

Safety Regulations & Specifications
- 8 -
1.2. Engine Specifications
Engine model
Items
GL08K
ETPCA/ETPBA BEB00/BEB02 BEB01
Engine type Water-cooled, 4 cycle in-line type
Turbo charged & intercooled
Ignition system Spark ignition lean burn
Combustion chamber type Open dish type
Used fuel CNG(Compressed natural gas)
Fuel supply system Venturi mixer throttle valve type
Cylinder liner type Replaceable dry liner
Timing gear system Gear driven type
No. of piston ring 2 compression ring, 1 oil ring
No. of cylinder – bore
× stroke (mm) 6 - 111 x 139
Total piston displacement (cc) 8,071
Compression ratio 10.6 : 1
Engine dimension
(length
× width × height) (mm) 1,260 x 1,080 x 1,009
Engine weight (kg) 745
Rotating direction (from flywheel) Counter clockwise
Firing order 1 – 5 – 3 – 6 – 2 – 4
Fuel ignition timing (B.T.D.C static) 10 ° ± 1 °
Engine control system ECM(Engine control module) type
Compression pressure (kg/cm
2
) 16 (at 200 rpm)
Valve clearance Intake valve 0.3
Exhaust valve 0.3
Intake valve Open at 16
° (B.T.D.C)
Close at 36
° (A.B.D.C)
Exhaust valve Open at 46
° (B.B.D.C)
Close at 14
° (A.T.D.C)
Lubrication method Full forced pressure feed type
Oil pump type Gear type driven by crankshaft
Engine oil pressure
Low idle (bar) 1.0 or More
High idle (bar) 3.0 ~ 5.4
Oil filter type Full-flow, cartridge type
Lubricating oil capacity (max./min.) (lit) 17/14 14.5/10.5 15.5/11.5
Oil cooler type Water cooled
Water pump Impeller type driven by belt
Cooling method Forced circulation by centrifugal impeller pump
Cooling water capacity(engine only) (lit) 13.7
Thermostat type (
°C )Wax pallet
type (79 ~ 94)
Wax pallet type
(71 ~ 85)

Safety Regulations & Specifications
- 9 -
1.3. Engine Power
tolerance : ±5 %
* Note : All data are based on operation without cooling fan at ISO 1585 (SAE J1349)
Alternator voltage – capacity (V – A) Bus: 24 – 150
Starting motor voltage – output (V – kW) Bus: 24 x 6.0, Truck: 24 x 6.0
Air compressor (cc/rev) Bus: 440, Truck: 300
Power steering pump
(lit/bar) Bus: 16/100, Truck: 15/125
Fuel System
System Air-Fuel mixer and throttle valve type
Control Air-Fuel ratio feed-back control
Injector type Solenoid valve type
Mixer type Multi-hole venturi type
Mixer location Between intercooler and throttle valve
Ignition System
Ignition Coil Inductive coil pack(coil on plug)
Spark Plug Double platinum electrode
Spark Plug Gap (mm) 0.39 ~ 0.4
Ignition Type Coil on plug type
Ignition Timing Controlled by ECM and ICM
(not user adjustable)
Control System
Control system On-highway heavy-duty
CNG engine control system
Voltage (V) 24
Component ECM, ICM, sensors, wire harness
Air Compressor Cooling method Water cooled
Driving method Belt driven
Turbocharger Model Holset HX40W
Type Water cooled, Exhaust gas driven
Battery capacity (V-AH) 24 – 150
Engine model Performance
Model Suffix
Ignition
timing
(BTDC
° )
Power
(PS / rpm)
Torque
(kg
• m / rpm)
Low idle
(rpm)
High idle
(rpm)
GL08K
ETPCA
10 °
230 / 2,200 82 / 1,400
600
2,530
ETPBA 240 / 2,300 90 / 1,400 2,530
BEB00 240 / 2,300 90 / 1,400 2,530
BEB01 240 / 2,300 90 / 1,400 2,530
BEB02 240 / 2,300 90 / 1,400 2,530
Engine model
Items
GL08K
ETPCA/ETPBA BEB00/BEB02 BEB01

Safety Regulations & Specifications
- 10 -
1.4. Engine Performance Curve
1.4.1. Engine performance curve (240PS)
1) Bus (240 PS)
Performance ISO 1585 (SAE J1349)
Output (max.) 240ps / 2,300rpm
Torque (max.) 90kg
• m / 1,400rpm
Fuel consumption (min.) 140g / ps
• h
EJ3OM001
1,400
100
140
1,000
180
220
260
1,200 1,600 1,800 2,000 2,200
90
100
80
70
300
150
145
140
(kg.m)Torque
Revolution (rpm)
Output (PS)

Safety Regulations & Specifications
- 11 -
2) Truck (260 PS)
Performance ISO 1585 (SAE J1349)
Output (max.) 260ps / 2,300rpm
Torque (max.) 100kg
• m / 1,400rpm
Fuel consumption (min.) 138g / ps
• h
EJ3OM002
0
100
1,400
1,000 1,200 1,600 1,800 2,200
2,000
140
150
300
200
70
90
110
80
100
130
800
(kg.m)Torque
Revolution (rpm)
Output (PS)

Safety Regulations & Specifications
- 12 -
1.5. Engine Assembly
1.5.1. Engine sectional view (longitudinal)
1. Cooling water pump 13. Ring gear
2. Piston 14. Tappet
3. Air compressor 15. Camshaft
4. Intake valve 16. Oil seal(rear)
5. Exhaust valve 17. Oil seal(rear)
6.
Intake valve spring 18. Crank shaft pulley
7. Breather 19. Crank gear
8. Exhaust valve spring 20. Vibration damper
9. Cylinder head cover 21. Oil pump
10. Cylinder head 22. Oil suction pipe
11. Cylinder block 23. Oil pan
12. Push rod 24. Crank shaft
1
2
3
45 678
9
10
11
12
13
14
15
16
17
18
19
20 21 22 23 24
EB8O1003

Safety Regulations & Specifications
- 13 -
1.5.2. Engine sectional view (cross)
1. Oil filter 7. Spark plug
2. Oil spray nozzle 8. Rocker arm
3. Connecting rod 9. Rocker arm bracket
4. Oil filler cap 10. Exhaust manifold
5. Idle pulley(air compressor) 11. Turbo charger
6. Ignition coil 12. Oil cooler
5
4
3
2
1
67
8
9
10
11
12
ED4OM051

Safety Regulations & Specifications
- 14 -
1.5.3. Engine assembly views
1) Bus engine
1. Flywheel housing 11. Oil pan 21. Exhaust manifold
2. Oil pressure sensor 12. Oil drain plug 22. Crank shaft pulley
3. Intake manifold 13. Fuel metering valve 23. Vibration damper
4. Throttle valve 14. Gas pressure &
Gas temperature sensor
24. Engine mounting bracket
5. Air pipe
(Turbocharger
 Intercooler)
15. Oil filter 25. Oil coller
6. Air compressor 16. Idle pulley 26. Starter
7. Power steering pump 17. Thermostat 27. Ignition coil
8. Ignition timing sensor 18. Cooling water pump 28. Cooling water temperature
sensor
9. Oil filler 19. Turbocharger 29. Intake manifold temperature
& pressure sensor
10. Oil level gauge 20. Solenoid valve
(Turbocharger)
30. Pre throttle pressure sensor
EJ3OM003
35 42076 29
16
18 17 19
2
21
22 23 24 25 26
1272830
14 13 15 8 10 11 12
9