DOOSAN Generator diesel engine DE12T, P126TI, P126TI-1, P126TI-II, PU126TI. Operation and 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 generator and power unit

diesel engines (DE12T, P126TI, P126TI-1, P126TI-II and PU126TI)

These economical and high-performance diesel engines (6 cylinders, 4 strokes, in-line, direct injection type)

have been so designed and manufactured to be used for the generator & power unit application. They

meet 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;

z Take old oil to an old oil disposal point only.

z Ensure without fail that oil and diesel fuel will not get into the sea or rivers and canals or the ground.

z Treat undiluted anti-corrosion agents, antifreeze agents, filter element and cartridges as special waste.

z 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 con-

tact 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.

2015.01.

950106-00121(G)

Doosan Infracore Co., Ltd.

CONTENTS

1. Safety Regulations

1.1. General Notes

1.2. Regulations Designed to Prevent Accidents

1.3. Regulations Designed to Prevent Damage to Engine and Premature Wear

1.4. Regulations Designed to Prevent Pollution

1.5. Notes on Safety in Handling Used Engine Oil

2. General Information

2.1. Engine Assembly

2.2. Engine Specification

3. Technical Information

3.1. Engine Model and Serial Number

3.2. Engine Type

3.3. Engine Timing

3.4. Valves

3.5. Lubrication System

3.6. Air Cleaner

3.7. Fuel System

3.8. Cooling System

3.9. V-belt Tension Check and Adjust

3.10. Turbocharger

3.11. Electrical Equipment

4. Commissioning and Operation

4.1. Preparation

4.2. Breaking-in

4.3. Inspections after Starting

4.4. Operation in Winter Time

4.5. Tuning the Engine

5. Maintenance and Care

5.1. Periodical Inspection and Maintenance

5.2. Lubrication System

5.3. Cooling System

5.4. Air Intake System

5.5. Fuel System

5.6. Injection Nozzle Maintenance (by authorized specialist personnel)

5.7. Turbocharger

6. Checking and Setting

6.1. Adjustment of Valve Clearance

6.2. Adjustment of Injection Timing

6.3. Cylinder Compression Pressure

6.4. V-belts

7. Operation Tip

7.1. Periodic Inspection Cycle

7.2. Trouble Shooting

7.3. Causes and Remedies

8. General Information

8.1. General Repair Instructions

8.2. Engine Characteristics

9. Disassembly and Reassembly of Major Components

9.1. Disassembly

9.2. Inspection

9.3. Reassembly

9.4. Breaking-in

118

10. Maintenance of Major Components

10.1. Cooling System

114

10.2. Lubricating System

118

10.3. Fuel Injection Pump

122

10.4. Turbocharger

160

11. Special Tool List

z Appendix

z Part & After service center

1. Safety Regulations

1.1. General Notes

Handling diesel engines and the necessary resources is no problem when the personnel commis-

sioned with operation and maintenance are trained accordingly and use their common sense.

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.

WARNING :

During operating the engine, be careful not to touch the safety guard of cooling fan.

Otherwise, by the rotating cooling fan, it can cause serious injuries such as a cutting of

fingers to you.

WARNING :

During operating the engine, be careful not to touch the safety guard of v-belt.

Otherwise, by the rotating v-belt, it can cause serious injuries such as a cutting of

fingers to you.

WARNING :

V-belt safety guard is an optional item at customers. In order to prevent accidents, you

should install a v-belt safety guard. If v-belt safety guard is not installed, you should not

access to the engine during operating. We will not be responsible for an accidents or

injury arising without an installation of v-belt safety guard.

WARNING :

Immediately after stopping the engine or during driving, be careful not to touch a part

of turbocharger. Otherwise, due to a hot turbocharger, it can cause you to severe burns.

If you need to contact the turbocharger of a hightemperature for maintenance, you

contact the turbocharger after enough waiting until be a low temperature.

WARNING :

Immediately after stopping the engine or during driving, be careful not to touch a part

of exhaust manifold or heat screen. Otherwise, due to a hot turbocharger, it can cause

severe burns to you. In particular, be careful not to touch the heat screen installed on

the exhaust manifold because it has also a high temperature.

1 -

Safety Regulations

WARNING :

If you need an emergency engine stop, use a device installed on a generator at first. It

is difficult to operate a 'manual emergency stop device' mounted in a fuel pump and it

can cause serious burns to you by contact with the exhaust manifold. Therefore, after

installing a separate auxiliary cable, use the 'manual emergency stop device'. We will

not be responsible for an accidents or injury arising without an installation of separate

auxiliary cable.

1.2. Regulations Designed to Prevent Accidents

1.2.1. During commissioning, 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 represen-

tative.

● For reasons of safety we recommend you attach a notice to the door of the engine room pro-

hibiting 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 persons 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 persons.

● When the engine is running, do not get too close to the rotating parts. Wear close-fitting

clothing.

● Do not touch the engine with bare hands when it is warm from operation risk of burns.

● Exhaust gases are toxic. Comply with the installation instructions for the installation of DOO-

SAN generator diesel engines which are to be operated in enclosed spaces.

Ensure that there is adequate ventilation and air extraction.

● Keep vicinity of engine, ladders and stairways free of oil and grease.

● Accidents caused by slipping can have serious consequences.

Safety Regulations

2 -

1.2.2. During 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 risk of burns and scalding. Do not touch oil drain valve 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.

● Open the coolant circuit only when the engine has cooled down. If opening while the engine

is still warm is unavoidable, comply with the instructions In the chapter entitled ìCoolingî.

● Neither tighten up nor open pipes and hoses (lube oil circuit, coolant circuit and any additional

hydraulic oil circuit) during the operation. The fluid 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 manufacturerís instructions when handling batteries.

CAUTION :

Accumulator acid is toxic and caustic. Battery gases are explosive.

1.2.3. 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 checking injectors, do not put your hands under the jet of fuel. Do not inhale at atom-

ized fuel.

● When working on the electrical system disconnect the battery earth cable first. Connect it up

again last in prevent short circuits.

3 -

Safety Regulations

1.3. Regulations Designed to Prevent Damage to Engine and Premature Wear

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. The injection pump must not

be adjusted without prior written permission of DOOSAN.

If faults occur, find the cause immediately and have it eliminate in order to prevent more seri-

ous of damage.

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”.

In addition to the above, note the following points.

● Never let the engine run when dry, i.e. without lube oil or coolant. Use only DOOSAN-

approved

service products (engine oil, anti-freeze and anticorrosion agent).

● Pay attention to cleanliness, The Diesel fuel must be free of water. See “Maintenance and

care”.

● 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. See “Maintenance and care”.

● Do not add so much engine oil that the oil level rises above the max. marking on the dip-

stick. Do not exceed the maximum permissible tilt of the engine. Serious damage to the

engine may result if these instructions are not adhered to.

● Always ensure that the testing and monitoring equipment (for battery charge, oil pressure,

and coolant temperature) function satisfactorily.

● Comply with instructions for operation of the alternator. See “Commissioning and operation”.

● Do not let the water pump run dry. If there is a risk of frost, drain the water when the

engine switched off.

1.4. Regulations Designed to Prevent Pollution

1.4.1. Engine oil, filter element, fuel filter

● 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 may be contaminated.

● Oil and fuel filter elements are classed as dangerous waste and must be treated as such.

1.4.2. 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

4 -

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, A nailbrush is an effective aid.

- Certain products make it easier to clean your hands.

- 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.

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.

5 -

Safety Regulations

2.1.3. Engine assembly views

1) DE12T

EA8M1004

1. Cooling fan

10. Flywheel housing

19. Thermostat

2. Cooling water pipe

11. Flywheel

20. Injection pump

3. Oil filler cap

12. Exhaust manifold

21. Oil level gauge

4. Cylinder head cover

13. Injection nozzle assembly

22. Mounting bracket

5. Turbocharger

14. Oil filter

23. Vibration damper

6. Oil drain valve

15. Fuel filter

24. Water pump

7. Alternator

16. Oil cooler

25. Fan drive

8. Oil pan

17. Intake manifold

26. Crankshaft pulley

9. Starter

18. Injection pipe

27. Breather

8 -

General Information

2) P126TI / P126TI-1 / P126TI-II / PU126TI

EI6OM009

1. Flywheel housing

8. Oil filter

15. Fuel filter

2. Air pipe to intercooler

9. Oil cooler

16. Intake manifold

3. Turbocharger

10. Injection pump

17. Breather filter

4. Oil filter cap

11. Oil level gauge

18. Oil pan

5. Cylinder head cover

12. Alternator

19. Mounting bracket

6. Cooling fan flange

13. Thermostat

20. Exhaust manifold

7. Flywheel

14. Air pipe to Intercooler

21. Starter

General Information

9 -

3) PU126TI (for Fire Pump)

EI6OM010

1. Intercooler

8. Oil cooler

15. Water pump

2. Breather filter

9. Injection pump

16. Oil pan

3. Oil filter cap

10. Oil level gauge

17. Cylinder head cover

4. Thermostat

11. Alternator

18. Exhaust manifold

5. Flywheel

12. Fuel filter

19. Starter

6. Flywheel housing

13. Intake manifold

20. Mounting bracket

7. Oil filter

14. Crankshaft pulley

21. Turbocharger

10 -

General Information

2.2. Engine Specification

Engine Model

DE12T

P126TI

P126TI-1

P126TI-II

PU126TI

Items

Water-cooled,

Water-cooled, 4 cycle in-line type

Engine type

4 cycle in-line

Turbo charged & intercooled

type Turbo charged

Combustion chamber type

Direct injection type

Cylinder liner type

Replaceable dry liner

Timing gear system

Gear driven type

No. of piston ring

Compression ring 2, oil ring 1

No. of cylinder-bore x stroke

4 - 123 x 155

(mm)

Total piston displacement

11,051

(cc)

Compression ratio

17.1 : 1

Engine dimension

1,365.5 x 870 x

1,383 x 870 x 1,207

(length x width x height) (mm)

1,046

Engine weight

(kg)

930

910

Rotating direction

Counter clockwise

(from flywheel)

Fuel injection order

1 - 5 - 3 - 6 - 2 - 4

Fuel injection timing

12°

16°

12°

16°

14°

(B.T.D.C static)

Injection pump type

Zexel in-line “P” type

Mechanical gover-

Governor type

Electric governor type(Ghana Control)

nor type (RSV)

Multi-hole type

Injection nozzle type

Multi-hole type (5 hole)

(5 hole)

Fuel injection pressure

220

1st : 1 60, 2nd : 220

(kg/cm²)

Compression pressure

28 (at 200 rpm)

(kg/cm²)

50Hz

60Hz

50Hz

60Hz

50Hz

condition

2,100rpm

(1,500rpm)

(1,800rpm)

(1,500rpm)

(1,800rpm)

(1,500rpm)

Power

205PS

245PS

328PS

378PS

356PS

418PS

360PS

Prime

(ISO 3046)

(151kW)

(180kW)

(241kW)

(278kW)

(262kW)

(307kW)

(265kW)

400PS

226PS

270PS

370PS

405PS

392PS

465PS

400PS

(294kW)

Stand by

(166kW)

(199kW)

(272kW)

(298kW)

(288kW)

(342kW)

(294kW)

Intake and exhaust valve

0.3

clearance (at cold)

(mm)

General Information

11 -

Engine Model

DE12T

P126TI

P126TI-1

P126TI-II

PU126TI

Items

Open at

18° (B.T.D.C)

Intake valve

Close at

34° (A.B.D.C)

Open at

46° (B.B.D.C)

Exhaust valve

Close at

14° (A.T.D.C)

Lubrication method

Full forced pressure feed type

Oil pump type

Gear type driven by crankshaft

Oil filter type

Full-flow, Cartridge type

Lubricating oil capacity

23 / 20

(max./min.)

(lit)

Oil cooler type

Water cooled

Water pump

Gear driven impeller type

Cooling Method

Pressurized circulation

Cooling water capacity

(engine only)

(lit)

Wax pallet type

Thermostat type

Wax pallet type (85C)

(95C)

Alternator voltage - capacity

24 - 45

(V - A)

Starting Motor voltage-output

24 - 6.0

(V-kW)

12 -

General Information

3. Technical Information

3.1. Engine Model and Serial Number

● The engine model and serial number

are located on the engine as illustrated.

Engine Number

● These numbers are required when

requesting warranty and ordering parts.

EI6OM011

EI6OM012

● Engine serial No. (example 1 : DE12T)

EBHOA900001

Serial No.

Production Year (2009)

Engine Model Suffix (EBHOA)

● Engine serial No. (example 2 : P126TI series)

EDIOA900001

Serial No.

Production Year (2009)

Engine Model Suffix (EDIOA ~ EDIOE)

● Engine serial No. (example 3 : PU126TI)

EDIPA900001

Serial No.

Production Year (2009)

Engine Model Suffix (EDIPA ~ EDIPB)

Technical Information

13 -

3.2. Engine Type

The Engines DE12T/ P126TI / P126TI-1 / P126TI-II / PU126TI are in-line vertical water-cooled 6-

cylinder four-stroke diesel engines with direct injection. DE12T is turbo-charged engine, and

P126TI / P126TI-1 / P126TI-II / PU126TI models are turbo-charged and inter-cooled engine.

3.2.1. Cylinder block

The cylinder block is a single piece of alloy cast iron. To increase its stiffness, it is extended to

a level below the crankshaft center line. The engine has replaceable dry cylinder liners and indi-

vidual cylinder heads with struck-in valve seat rings and replaceable valve guides,

3.2.2. Piston con-rod / crankshaft

The forged crankshaft is a ingrate type (Counterweight is integrated with crank shaft body). Radial oil

seal on crankshaft and flywheel are provided to seal the flywheel housing inside penetrations.

The con-rods (connecting rods) are die-forged, diagonally split and can be removed through the top

of the cylinders together with the pistons. Crankshaft and connecting rods run in steel-backed lead

bronze ready-to fit type bearings.

3.3. Engine Timing

Camshaft, oil pump and injection pump are driven by a gear train arranged at the front end.

Injection pump gear

Camshaft gear

Water pump gear

(Z = 72)

(Z = 29)

Idle gear

(Z = 52)

Crankshaft gear

(Z = 36)

Oil pump idle gear

(Z = 31)

Oil pump drive gear

(Z = 32)

EA8O3002

14 -

Technical Information

3.4. Valves

The overhead valves are actuated via chilled cast iron tappets, push rods and rocker arms from

the camshaft.

3.5. Lubrication System

The engine is equipped with force-feed lubrication.

The pressure is produced by a gear pump whose drive gear is in direct mesh with the crankshaft

gear at the front end of cylinder block.

The oil pump draws the oil from the oil sump and delivers it through the oil cooler and oil filter to

the main distributor gallery and from there to the main bearings, big-end bearings and camshaft

bearings as well as to the small-end bearings and the rocker arms.

The injection pump and the turbocharger are also connected to the engine lubricating system.

The cylinder walls and timing gears are splash lubricated.

Each cylinder has an oil jet provided for cooling the underside of the pistons.

The lube oil is cleaned in a full-flow oil filter.

Rock arm

Cam shaft

W/P

BRG.

Piston

I/P

Con-rod bearing

Main bearing

Oil jet valve

T/C

1.3 bar

Main gallery

Filter

Oil pump

Cooler

Relief valve

4.4 bar

Valve : 10 bar

Valve : 5 bar

Valve : 3 bar

ED5OM001

Technical Information

15 -

3.5.1. Oil cooler

An oil cooler is provided between the oil

filter and the cylinder block. This cooler is

a flat tube type with turbulence inserts

and operated by the coolant.

3.5.2. Oil filter

Check for oil pressure and oil leaks, and

repair or replace the oil filter if necessary.

Change the oil filter cartridge simultane-

Oil filter (Cartridge)

ously at every replacement of engine oil.

Oil filter head

EQM4010I

3.6. Air Cleaner

In case that elements are deformed, dam-

aged or if the air cleaner has a crack,

replace it.

By the definite interval, the elements must

be cleaned and replaced.

- Cleaning of air cleaner element: Every 200 hours.

- Changing of air cleaner element: Every 400 hours.

16 -

Technical Information

3.7. Fuel System

The fuel is delivered by the fuel feed pump via the fuel filter to the injection pump and from there

to the injection nozzles.

The fuel is sprayed into the cylinders through nozzles fitted in screw-fit injection nozzle holders in

the cylinder heads.

Excessively delivered fuel and leak fuel from the nozzle flow through the return pipe back to the

tank.

A strainer is arranged ahead of the fuel feed pump.

3.7.1. Fuel filter

This fuel filter has two functions not only

oil filtering but also water separating.

Before entering the suction chamber of

the injection pump, the fuel is cleaned in

a strainer of fuel feed pump and a fuel

filter.

Drain water in cartridge with loosening

the cock under filter manually

(6) from

time to time.

EA2O4009

The fuel filter should be replaced at every

400 hours.

3.7.2. Fuel requirements

DOOSAN marine diesel engines was designed to use Number 2-D diesel fuel or equivalent that

meets specification DIN 51601-DK. For maximum fuel economy, Number 2-D fuel whenever pos-

sible. When temperatures are below -7 C (20 °F), use Number 1-D fuel. If Number 1-D fuel is

not available, the mixture of one kerosene to two gallons of Number 2-D fuel can be used. Once

kerosene has been added, the engine should be run for several minutes to mix the fuel.

3.7.3. How to select fuel oil

Fuel quality is an important factor in obtaining satisfactory engine performance, long engine life,

and acceptable exhaust emission levels. DOOSAN engines are designed to operate on most die-

sel fuels marketed today. In general, fuels meeting the properties of ASTM Designation D975

(grades 1-D and 2-D) have provided satisfactory performance.

The ASTM 975 specification, however, does not in itself adequately define the fuel characteristics

needed for assurance of fuel quality.

The properties listed in the fuel oil selection chart below have provided optimum engine perfor-

mance. Grade 2-D fuel is normally available for generator service. Grade 1-D fuel should not be

used in pleasure craft engines, except in an emergency.

Technical Information

17 -

Fuel oil selection chart

General Fuel

ASTM

No. 1

No. 2

DIN 51601

Classification

Test

ASTM 1-D

ASTM 2-D

Gravity,°API ^#)

D 287

40 ~ 44

33 ~ 37

0.815 ~ 0.855

Flash Point

D 93

100 (38)

125 (52)

131 (55)

Min. F (C)

Viscosity, Kinematic

D 445

1.3 ~ 2.4

1.9 ~ 4.1

1.8 ~ 10

CST 100 F (40 C )

Cloud Point F ^#)

D 2500

See Note 1)

Sulfur Content

D 129

0.5

0.15

wt%, Max.

Carbon Residue

D 524

0.15

0.35

0.1

on 10%, wt%, Max.

Accelerated Stability

Total Insolubles

D 2274

1.5

mg/100 ml, Max. ^#)

Ash, wt%, Max.

D 482

0.01

Cetane Number, Min. ^#)

D 613

> 45

Distillation

D 86

Temperature, F(C)

IMP, Typican ^#)

350 (177)

375 (191)

10% Typical ^#)

385 (196)

430 (221)

50% Typical ^#)

45 (218)

510 (256)

680 (360)

90% ⁺⁾

500 (260) Max.

625 (329) Max.

End Point ^#)

550 (288) Max.

675 (357) Max.

Water & Sediment

D 1796

0.05

%, Max.

^#) Not specified In ASTM D 975

⁺⁾ Differs from ASTM D 975

NOTE :

1. The cloud point should be 6C(10F) below the lowest expected fuel temperature to prevent

clogging of fuel fitters by crystals.

18 -

Technical Information

3.8. Cooling System

The engine has a liquid-cooling system. The fresh water pump is a maintenance-free by gear from the

crankshaft.

Depending on the agreed extent of delivery and the design of the engine, the coolant circuit can be

equipped with temperature monitors which, in the event of loss of coolant, shut the engine down.

● Check the coolant level of the expansion tank by removing the expansion tank filler cap, and

add coolant if necessary.

● When injecting antifreeze solution, first drain out the old coolant from the cylinder block and

radiator, and then clean them with cleaning solution.

● Be sure to mix soft water with antifreeze solution.

Water pipe

Thermostat

Cylinder head

Reserve tank

Cylinder block

Water pump

EJM4001I

Technical Information

19 -

3.8.1. Coolant pressure cap

Check the pressure valve opening pres-

sure using a expansion tank cap tester.

Replace the filler cap assembly if the

Rediater Cap

measured valve does not reach the spec-

ified limit.

(pressure valve opening pres-

sure : 0.5 kg/cm2)

Rediater

NOTE :

Because it is dangerous to open the

pressure cap quickly when coolant is

hot, after lowering the inside

pressure of the tank by slow-opening

at first open it fully.

EA5O3002

3.8.2. Cooling water

● Regarding the cooling water that is to be used for engine, the soft water not the hard water must be

used.

● The engine cooling water can be used diluting it with antifreezing solution 40% and the additive for

rust prevention (DCA4) 3 ~ 5 %.

● The density of above solution and additive must be inspected every 500 hours to maintain it properly.

NOTE :

The proper density control of antifreezing solution and rust preventing additive will be

able to prevent the rusting effectively and maintain the stable quality of engine.

For the improper control might give the fatal damage to the cooling water pump and

cylinder liners, detail care is needed.

● Since DE12T , P126TI / P126TI-1 and P126TI-II / PU126TI cylinder liner is dry type, particu-

larly the cooling water control should be applied thoroughly.

● The density of antifreezing solution and additive for rust prevention is able to be confirmed by

the cooling water test kit. (Fleetguard CC2602M)

● How to use the cooling water test kit

1) When the cooling water temp. of engine is in the range of 10 ~ 55 C, loosen the plug for

cooling water discharge and fill the plastic cup about a half.

NOTE :

In taking the cooling water sample, if the water in auxiliary tank were taken, it is hard

to measure the accurate density. Take the cooling water sample necessarily loosening

the cooling water discharge plug.

20 -

Technical Information

2) At the state of a test paper soaked in the sampled water, after taking the paper out

through water agitation, shake off the water.

3) Wait for about 45 sec. till the color change of test paper.

NOTE :

However, it should not elapse longer than 75 sec, and if it did, the hue would change.

Make the numerical value by comparing the test paper which hue has changed with the

color list of label on storage bottle.

By comparing the hue changed into yellowish green or so with the green color indication of

test paper storage bottle, confirm the density. (Then, the density indication must be in the

hue range of 33% to 50%).

The brown at the middle of test paper and the lower pink color indication represent the

additive state for rust prevention, and the proper range is that the meeting numerical value

of brown (vertical) and pink color (horizontal) locates in the range of 0.3 to 0.8 at the color

list of label on the test paper storage bottle.

In case of less than 0.3, replenish the additive for rust prevention (DCA4), and in case of

more than 0.8, pour out the cooling water about 50% and then readjust the density after

refilling with clean fresh water.

● Amount of Anti-freeze in winter

Ambient

Cooling water (%)

Anti-freeze (%)

Temperature (C)

Over -10

-10

-15

-20

-25

-30

-40

3.9. V-belt Tension Check and Adjust

By the finger-pressure the belt is pressed

Press here

by 10 mm ~ 15 mm between the fan pul-

15mm

ley and the alternator pulley in normal con-

Alternator

Fan

dition. For the adjustment of the tension,

Pulley

loosen the adjusting bolts which support

the alternator, adjust the tension and

V-belt

tighten the bolts again.

Crank Pulley

EA8O3005

Technical Information

21 -

3.10. Turbocharger

The exhaust gases of the engine are passed through the turbine rotor of the turbocharger. Air

compressor impeller mounted on the same shaft draws in fresh air and delivers it at a higher

pressure to the cylinders.

The turbocharger is naturally air-cooled. Lubrication of the main bearing is by oil under pressure

from the engine lubricating system.

EA6O3004

1. Compressor casing

A. Air inlet

2. Turbine casing

B. Gas outlet

3. Compressor wheel

C. Gas inlet

4. Impeller

D. Oil supply

5. Turbine

E. Oil return

22 -

Technical Information

3.11. Electrical Equipment

3.11.1. Alternator

The alternator is fitted with integral silicon rectifiers. A transistorized regulator mounted on the

alternator body interior limits the alternator voltage. The alternator should not be operated

except with the regulator and battery connected in circuit to avoid damage to the rectifier and

regulator.

P-TAB : KET GP 890545

TACHOMETER CHARGE INDICATOR

RPM

M6 x 1.0 THREAD

ALDO SYSTEM FREQUENCY =

BATTERY TERMINAL

"L" Terminal

"R" Terminal

CONNECTOR HOUSING

KET MG 620042

TERMINAL

KET ST 740254

EA8O3006

The alternator is maintenance-free, nev-

To Battery +

ertheless, it must be protected against

Regulator

dust and, above all, against moisture

and water.

RL = 150~250 OHM

Operate the alternator according to

the instructions given in the chapter.

EA8O3007

Technical Information

23 -

3.11.2. Starter motor

The sliding-gear starter motor is flanged to the rear of the flywheel housing on the left-hand side.

When the starting key switch is turned on, the starter motor pinion flies out and engages the ring

gear of the flywheel. Then the main contact is closed, current flows, and the engine is started. After

the engine starts, the pinion automatically returns to its initial position when the starting key switch

is released. Once the engine starts, the starting key switch should be released immediately. Other-

wise, the starter motor may be damaged or burned out.

In case of repairing the engine dip the pinion of the starter and ring gear into the fuel and remove

the corrosion with brush. After that apply the grease on them to protect the corrosion. Whenever

you clean the starter, always pay attention not to occur the electric short due to entering the water.

TERMINAL "B"

TERMINAL S/W

24V x 6.0kW

M10 x P1.5

M5 x P0.8

EA8O3008

Always protect starter motor against moisture.

WARNING :

S/W

Always disconnect the battery earth

cable before starting work on the

Motor

S/W

electrical system. Connect up the earth

cable last, as there is otherwise a risk

S/W

of short-circuits.

2.5A(20^oC 24V)

EA8O3009

24 -

Technical Information

4. Commissioning and Operation

4.1. Preparation

At the time of initial commissioning of a new or overhauled engine make sure to have observed

the “Technical Information for the installation DOOSAN generator engines”.

● Oil filler neck on cylinder head cover

Before daily starting of the engine, check the fuel, coolant and oil level, replenish if necessary.

The notches in the dipstick indicate the highest and lowest permissible oil levels

The oil required in the sump is specified in the “Engine Specification”.

NOTE :

The oil required to fill the oil fillers and pipes depends upon the engine and use and

must be determined individually at the time of initial commissioning. (Make the Max and

Min. marks of the determined quantity on the oil level gauge.)

● Cleanliness

Ensure outmost cleanliness when handling fuels, lubricants and coolants.

4.2. Breaking-in

4.2.1. Operation of a new engine (Break-In)

Because the sliding surfaces of a new engine are not lapped enough, the oil film can be

destroyed easily by overload or overspeed and the engine life-time may be shortened.

Therefore the following things must be obeyed by all means.

Up to the first 50 hours

● Engine should be run at fast idling until the temperature of the engine becomes normal oper-

ating condition.

● Overload or continuous high speed operation should be avoided.

● High speed operation with no load should be prevented.

● Abrupt start and stop of the engine should be avoided.

● Engine speed must be under 70% of its maximum speed.

● Maintenance and inspection must be accomplished thoroughly.

Commissioning and operation

25 -

4.2.2. Check points for break-in

During the break-in (the initial running of the engine) period, be particularly observant as follows:

1) Check engine oil level frequently. Maintain oil level in the safe range, between the “min.” and

“max.” marks on dipstick.

NOTE :

If you have a problem getting a good oil level reading on dipstick, rotate dipstick 180°

and re-insert for check.

2) Watch the oil pressure warning lamp. If the lamp blinks, it may be the oil pick-up screen is

not covered with oil. Check oil dipstick. Add oil to the oil pan, if required. Do not overfill. If

level is correct and the status still exists, see your DEALER for possible switch or oil pump

and line malfunction.

NOTE :

Oil pressure will rise as RPM increases, and fall as RPM decreases. In addition, cold oil

will generally show higher oil pressure for any specific RPM than hot oil. Both of these

conditions reflect normal engine operation.

3) Watch the engine water temperature gauge and be sure there is proper water circulation. The

water temperature gauge needle will fluctuate if water level in expansion tank is too low.

At the end of the break-in period, remove break-in oil and replace the oil filter. Fill oil pan

with recommended engine oil. Refer to following table.

Oil pan (only)

DE12T

23 liter

P126TI / P126TI-1 /

23 liter

P126TI-II / PU126TI

4.2.3. Operating after break-in

When starting a cold engine, always allow the engine to warm up gradually. Never run the

engine at full throttle until the engine is thoroughly warmed up. Be sure to check the oil level

frequently during the first 50 hours of operation, since the oil consumption will be high until the

piston rings are properly seated.

26 -

Commissioning and operation

4.3. Inspections after Starting

During operation the oil pressure in the engine lubrication system must be monitored. If the mon-

itoring devices register a drop in the lube oil pressure, switch off the engine immediately.

And the charge warning lamp of the alternator should go out when the engine is running.

● Do not disconnect the battery or pole terminals or the cables!

● If, during operation, the battery charge lamp suddenly lights up, stop the engine immediately

and remedy the fault in the electrical system!

● Engine should be stopped if the color, the noise or the odor of exhaust gas is not normal.

● Confirm the following things through warning lamps and gauge panel.

4.3.1. Pressure of lubricating oil

The normal pressure comes up to 1 kg/cm2 (1.0 bar) at idling and 3 ~ 5 kg/cm2 (3.0 ~ 4.9 bar)

at maximum speed. If the pressure fluctuates at idling or does not reach up to the expected

level at high speed, shut down the engine immediately and check the oil level and the oil line

leakage.

4.3.2. Temperature of cooling water

The cooling water temperature should be 71 ~ 85C in normal operating conditions. Abnormally

high cooling water temperature could cause the overheating of engine and the sticking of cylinder

components. And excessively low cooling water temperature increases the fuel consumption,

accelerates the wears of cylinder liners and shortens the engine life-time.

4.4. Operation in Winter Time

Pay special attention to the freezing of cooling water and the viscosity of lubricating oil.

4.4.1. Prevention against the freeze of cooling water

When not using anti-freeze, completely discharge the whole cooling water after engine running.

The freeze of cooling water causes the fatal damages of the engine. Because the anti-freeze is

used to prevent cooling water from freeze, consult “The amount of anti-freeze”.

4.4.2. Prevention against excessive cooling

Drop of thermal efficiency caused by excessive cooling increases fuel consumption, therefore pre-

vent the engine from excessive cooling. If the temperature of coolant does not reach to normal

condition

(71 ~ 85 C) after continuous operation, examine the thermostat or the other cooling

lines.

4.4.3. Lubricating oil

As cold weather leads to the rise of oil viscosity, engine speed becomes unstable after starting.

Therefore the lubricating oil for winter should be used to prevent this unstability. Refer to “Lubri-

cating System Section”.

Commissioning and operation

27 -

4.5. Tuning the Engine

The purpose of an engine tune-up is to restore power and performance thatís been lost through

wear, corrosion or deterioration of one or more parts or components. In the normal operation of

an engine, these changes can take place gradually at a number of points, so that itís seldom

advisable to attempt an improvement in performance by correction of one or two items only. Time

will be saved and more lasting results will be obtained by following a definite and thorough proce-

dure of analysis and correction of all items affecting power and performance.

Economical, trouble-free operation can better be ensured if a complete tune-up is performed once

every years, preferably in the spring. Components that affect power and performance to be

checked are:

● Components affecting fuel injection ;

Nozzle, delivery valve, fuel filter, water separator, etc.

● Components affecting Intake & exhaust ;

Air filter, inter-cooler, turbo, silencer, etc.

● Components affecting lubrication & cooling ;

Air & oil filter, anti- freeze, etc.

28 -

Commissioning and operation

5. Maintenance and Care

5.1. Periodical Inspection and Maintenance

In order to insure maximum, trouble-free engine performance at all times, regular inspection,

adjustment and maintenance are vital.

● Daily inspections in below figure should be checked every day.

● The maintenance should be executed thoroughly at regular intervals.

(Refer to " 7.1. Periodic Inspection Cycle")

5.2. Lubrication System

5.2.1. Exchanging of lubrication oil

Engine oil and the oil filter are important factors affecting engine life. They affect ease of start-

ing, fuel economy, combustion chamber deposits and engine wear. Refill and drain oil pan every

50 hours of operation or 6 months whichever occurs first. At the end of the break-in period (50

hours), change the oil sump oil and replace the oil filter.

5.2.2. Oil level

Check the oil level in the engine sump

daily with a dipstick.

● The notches in dipstick must indicate

the oil level between the max. and the

min. permissible.

● The oil level should be checked with

the engine horizontal and only after it

has been shut down for about 5 min-

utes.

EA4O4001

● Examining the viscosity and the con-

tamination of the oil smeared at the

dipstick replace the engine oil if neces-

sary.

CAUTION :

Do not add so much engine oil that

the oil level rises above the max.

marking on the dipstick. Over lifting

will result in damage to the engine.

Maintenance and Care

29 -

5.2.3. Oil exchange procedure

While the oil is still hot, exchange oil as

follows:

● Take out the oil dip dipstick.

● Remove the drain valve from oil pan

and the drain plug form oil filter head,

then drain out the engine oil into a

container.

Drain valve

EA8O5001

● Reassemble the drain valve with the

oil pan and the drain plug with oil filter

head after draining out the engine oil.

EA2O4001

● Refill with new engine oil at the oil

filler neck on the head cover and the

lubricating oil in accordance with the

Oil filler cap

oil capacity of the engine through oil

filler. Be careful about the mixing of

dust or contaminator during the supple-

ment of oil. Then confirm that oil level

Cylinder head cover

gauge indicates the vicinity of its maxi-

mum level.

EA7O5003

● For a few minutes, operate the engine

at idling in order to circulate oil

through lubrication system.

● Thereafter shut down the engine. After

waiting for about

10 minutes measure

the quantity of oil and refill the addi-

tional oil if necessary.

30 -

Maintenance and Care

● Recommend of lubricating oil

Initial factory filling is high quality break-in oil

(API Service CH-4 grade). During the break-in

period (50 hours), check the oil level frequently. Somewhat higher oil consumption is normal

until piston rings are seated. The oil level should be maintained in the safe range between

Min. and Max. mark on the dipstick. To obtain the best engine performance and engine life,

Engine oil is specified by API Service, lettered designations and SAE viscosity numbers. If the

specified engine oil is not available, use a reputable brand of engine oil labeled for API Ser-

vice CH-4 and SAE viscosity 15W40 or 10W40. Refer to oil identification symbol on the con-

tainer.

Engine oil viscosity - ambient temperature

SAE 20, 20W

SAE 40, 50

Single

SAE

10W

SAE 30

grade

Ambient

-30 C

-15 C

-0 C

15 C

25 C

30 C

temp

(-20 F)

(-0 F)

(-32 F)

(60 F)

(80 F)

(90 F)

Multi

grade

SAE 10W - 30

SAE 15W - 40

SAE 10W - 40, 20W - 40, 20W - 50

SAE 5W - 20

EA4M1008

Maintenance and Care

31 -

5.2.4. Replacement of oil filter cartridge

At the same times of oil exchanges,

replace the oil filter cartridge.

● Drain engine oil by loosening the drain

plug on the filter head.

Cartridge

CAUTION :

Don’t forget tightening the drain plug

after having drained engine oil.

● Loosen the oil filter by turning it

counter- clockwise with a filter wrench.

● With a rag wipe clean the fitting face

of the filter body and the oil filter body

so that new oil filter cartridge can be

Drain plug

seated properly.

EA7O5004

● Lightly oil the O-ring and turn the oil

filter until sealing face is fitted against

the O-ring. Turn

1-1/4 turns further

with the filter wrench.

NOTE :

is strongly advisable to use

DOOSAN genuine oil filter cartridge

for replacement.

5.3. Cooling System

The coolant must be changed at intervals

1,200 hours operation or six months

whichever comes first. If the coolant is

being fouled greatly, it will lead an engine

overheat or coolant blow off from the

expansion tank.

32 -

Maintenance and Care

5.3.1. Coolant draining

1) Remove the pressure cap.

2) Open the drain valve at the radiator

lower part to drain the coolant as the

right figure.

Drain Valve

EA5O4002

3) Loosen the coolant drain plug. Loosen

the coolant drain plug of the cylinder

block.

EI6OM001

CAUTION :

When removing the pressure filler cap while the engine is still hot, cover the cap with a

rag, then turn it slowly to release the internal steam pressure. This will prevent a person

from scalding with hot steam spouted out from the filler port.

5.3.2. Cleaning of the cooling system inside circuit (by authorized specialist personnel)

When the cooling system circuits are fouled with water scales or sludge particles, the cooling

efficiency will be lowered.

Investigations have shown that in many cases the poor condition of the coolant and /or the cool-

ing system accounts for damage to the water pump mechanical seal, The poor condition of the

cooling system is normally due to use of unsuitable or no anti-freezing agents and corrosion

inhibitor or defect, not early enough replaced covers for filler neck and working valves.

If twice in a short time the water pump of an engine develops leases or the coolant is heavily

contaminated (dull, brown, mechanically contaminated, gray or black signs of a leakage on the

water pump casing) clean the cooling system prior to removing that water pump as follows.

1) Drain coolant.

2) Remove thermostats, so that the whole cooling system is immediately flown through when

cleaned.

Maintenance and Care

33 -

3) Fill the cooling system with a mixture of potable water and 1.5% by volume of cleaner. (Hen-

kel P3T5175)

4) Warm up engine under load. After a temperature of 60°C is reached, run engine for a further 15

minutes.

5) Drain cleaning fluid.

6) Repeat steps 3) and 4).

7) Flush cooling system.

8) Replace drain plug by drain plug with a bore of 8 mm diameter.

9) Fill cooling system with hot water.

10) Run engine at idle for 30 minutes. At the same time continuously replenish the water leaking

from the bore in drain plug by adding fresh water.

Periodically clean the circuit interior with a cleaner.

- Cooling system cleaning interval: Every 1,200 hours.

5.3.3. Intercooler

The intercooler is air to air type and has a large cooling fan capacity. The intercooler life and perfor-

mance depends on the intake air condition greatly. Fouled air pollutes and clogs the air fins of inter-

cooler. As a result of this, the engine output is decreased and engine malfunction is occurred. So

you always check whether the intake air systems like air filter element are worn or polluted.

Air/air intercooler

with downstream

radiator

(Combined radiator)

Cooling air

Hot charge air

from compressor

Recooled charge air

to intake pipe (max. 50 C)

EA5O4003

● Cleaning

In order to maintain the heat transfer efficiency of the intercooler, it is necessary to clean it at

regular intervals.

Cleaning of intercooler fins: Every 600 hours.

34 -

Maintenance and Care

5.4. Air Intake System

5.4.1. Maintenance

(only when engine is

Air cleaner

switched off)

assembly

Empty the dust bowl

(7) regularly. The

bowl should never be filled more than

halfway with dust.

On slipping off the two clamps

(3), the

dust bowl can be removed. Take off the

cover (6) of the dust bowl and empty.

Be careful to assemble cover and bowl

EK00352A

correctly.

There is a recess in the cover rim and a

lug on the collector which should register.

Where the filter is installed horizontally,

watch for “top” mark on cleaner bowl.

5.4.2. Changing filter element

CAUTION :

Do not allow dirt to get into the

clean air end.

On removing the hexagon nut, take out

the dirty cartridge and renew or clean.

Wipe the cleaner housing with a damp

cloth, in particular the sealing surface for

the element.

EA6O5013

NOTE :

Unless the maximum number of

cleanings

(up to

5 x) have been

done, the filter cartridge should be

renewed every two years or

4,000

hours operation.

Maintenance and Care

35 -

5.4.3. Cleaning filter elements

● By compressed air (wear goggles)

For the purpose, the air gun should be

fitted with a nozzle extension which is

bent

90 at the discharge end and

which is long enough to reach down

inside to the bottom of the element.

Moving the air gun up and down, blow

out the element from the inside (maxi-

mum 500 kPa - 5 bar) until no more

EA6O5014

dust comes out of the filter pleats.

● By washing

Before washing, the element should be

precleaned by means of compressed air,

as described above.

Then allow the element to soak in luke-

warm washing solvent for

10 minutes,

and then move it to and for in the sol-

vent for about 5 minutes.

Rinse thoroughly in clean water, shake

EA6O5015

out and allow drying at room tempera-

ture. The cartridge must be dry before it

is reinstalled. Never use steam sprayers,

petrol

(gasoline), alkalis or hot liquids

etc. to clean the filter elements.

● Knocking out dirt by hand

In emergencies, when no compressed air or cleaning agent is available, it is possible to clean the filter

cartridge provisionally by hitting the end disk of the cartridge with the ball of oneís thumb.

Under no circumstances should the element be hit with a hard object or knocked against a

hard surface to loosen dirt deposits.

● Checking the filter cartridge

Before reinstalling the cartridge, it must be

checked for damage e.g. to the paper

pleats and rubber gaskets, or for bulges

and dents etc. in the metal casket.

Cracks and holes in the paper pleating

can be established by inspecting the car-

tridge with a flashlight. Damaged cartridges

should not be reused under any circum-

EA6O5016

stances. In cases of doubt, discard the

cartridge and install a new one.

36 -

Maintenance and Care

DOOSAN Generator diesel engine DE12T, P126TI, P126TI-1, P126TI-II, PU126TI. Operation and Maintenance Manual - page 1