Daewoo DE12 Install guide

65.99892-8030B Shop Manual
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product to the market place. These improvements can be implemented at any time with no obligation to
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Shop Manual
65.99892-8030B
DE12, DE12T &
DE12TI & DE12TIS
DIESEL ENGINE

FOREWORD
This manual has been prepared to help you use and maintain the DE series diesel engines (DE12,
DE12T, DE12TI and DE12TIS) safely and correctly.
These economical and high-performance diesel engines(6 cylinders, 4 strokes, in-line, direct injection
type) have been designed and manufactured to be used for overland transport or industrial pur-
pose. They meet all the requirements such as low noise, fuel economy, high engine speed and
durability.
Nonetheless, to obtain the best performance and long life of an engine, it is essential to operate it
appropriately and to carry out periodic checks as instructed in this manual. You are requested to
thoroughly read this manual from cover to cover and to acquaint yourself with all the information
contained in this manual.
All information, illustration and specifications continued in this literature are based on the latest
product information available at the time of publication approval. The right is reserved to make
changes at any time without notice.
Please contact Daewoo dealer for the answers to any questions you may have about DE series
engine's features, operation or manuals.

CONTENTS
1. General information ............................................................................................................... 1
1.1. Engine characteristics 1.4. Engine performance curve
1.2. Main data and specifications 1.5. Exterior view of engine
1.3. Engine specification(’98 type)
2. Major maintenance .............................................................................................................. 22
2.1. Preventive maintenance 2.2. Diagnostics and troubleshooting
for the engine
3. Disassembly and reassembly of major components ....................................................... 37
3.1. Disassembly 3.3. Reassembly
3.2. Inspection 3.4. Breaking-in
4. Maintenance of major components .................................................................................... 79
4.1. Cooling system 4.3. Fuel system
4.2. Lubricating system 4.4. Turbocharger
5. Scan pole diagnosis for DE12TIS ..................................................................................... 142
5.1. Wire harness connection 5.4. Sensor data
5.2. System & Vehicle selection 5.5. Actuator test
5.3. Self-diagnosis(current) 5.6. Flight record
6. Maintenance specifications ............................................................................................... 154
6.1. Tightening torque 6.2. Maintenance specification table
¥
WORLDWIDE NETWORK

1. General information
1.1. Engine characteristics
1.1.1. OMEGA combustion bowl
The OMEGA combustion bowl is a unit designed to perform high-efficiency, low- emission
combustion. As the rim around the combustion bowl port of the upper of the piston has been
machined in a smaller size than the interior of the combustion bowl, strong swirl is produced
in the combustion bowl and strong squish flow makes the fuel be mixed more sufficiently with
air.
Due to the application of OMEGA combustion system and optimal ultilization of intake and
exhaust port configuration within the cylinder head, the DE12 series engines discharge a
very low level of hazardous exhaust gases such as smoke, nitrogen oxide, hydrocarbon, or
carbon monoxide and thus ensure high performance and low fuel consumption.
- 1 -
EA2M1001
<Figure. 1-1> OMEGA combustion bowl

1.1.2. Wastegated turbocharging system
1) What is the wastegated turbocharging system?
Turbocharger is a system designed to pressurize the intake air to increase engine output and
decrease fuel consumption by using the energy of exhaust gas discharged from the engine.
However, the turbocharger has a weak point at low engine speed, its performance may drop,
thus performance at low speed is relatively low.
The WASTEGATED TURBOCHARGING SYSTEM is an up-to-date turbocharging system
remedying such a defect, and the working principle is as follows:
A small-sized high performance turbine is used to improve engine performance at low
speeds. As high charging efficiency can be obtained even If a small amount of exhaust gas
is present at low speed. On the other hand, if higher charging pressure is produced than
what is present at high speed, fuel consumption increases. To correct this, part of exhaust
gas is forced to be discharged into the exhaust manifold through the waste gate, not through
the turbine.
The waste gate is controlled by the ACTUATOR mounted in the turbocharger, and if the
pressure in the turbocharger becomes higher than what is required for the engine, the waste
gate is forced to open.
2) DE12T, DE12TI and DE12TIS engines are featured by the application of turbochager so that
the torque in low speeds can be increased by 30% or more, not only to create high perfor-
mance, just from the time of starting off the vehicle but also to greatly reduce fuel consump-
tion.
- 2 -
Compressed air outlet por
Intake air
Turbine
Turbine port
Exhaust gas
outlet port
Waste gate
Compressor
Actuator
EQM1003I
<Figure 1-3> Turbochager

1.2. Main data and specifications
Engine Model DE12 DE12T DE12TI DE12TIS
Type In-line, 4-stroke, vertical type
Combustion chamber type OMEGA Combustion bowl
Fuel injection Direct injection type
BoreBstroke-No. of cylinders 123mm B 155 - 6
Total displacement 11,051cc
Compression ratio 17.1:1 17.1:1 16.5:1 16.8
Maximum power(PS) 225 ps/2,200 rpm 300 ps/2,200 rpm 340 ps/2,100 rpm
Maximum torque 81.5 kg.m/1,400 rpm 110 kg.m/1,300 rpm 135 kg.m/1,260 rpm
Injection timing 12° BTDC 9° BTDC 12° BTDC 1.0° BTDC
Firing order 1-5-3-6-2-4
Injection pump type S3000 S3000 S3S HD-TICS
Governor type RFD-C/RLD RFD-C RFD-D RLD-J
Timer type SP SP SPG Electronically control
Nozzle type Multi-hole type(5-N0.29) Multi-hole type(5-N0.31) Multi-hole type(5-N0.33) Multi-hole type(5-N0.29)
Feed pump type K-P K-P K-PS
Valve Timing
Intake valve open at BTDC 18° BTDC 18°
Intake valve close at ABDC 34° ABDC 32°
Exhaust valve open at BBDC 46° BBDC 70°
Exhaust valve close at ATDC 14° ATDC 30°
Oil pump type Gear type
Oil cooler type Water-cooler
Fuel filter type Full flow type
Oil capacity 20M(Oil pan 17M)
Coolant capacity 19M
Thermostat type Wax-pallet
Starter : Voltage-output 24V-6.0Kw
Alternator : Voltage-capacity 24V-45A
- 3 -

1.3. Engine specification(’98 type)
- 4 -
Item DE12-228 DE12TI-280 DE12TI-310 DE12TIS
Manufacturer DHI
Mounting location Under Seat
Starting type SELF
Engine type Diesel 4 Cycle Turbocharged & Intercooled
Cylinder(No. arrangement) In-line, vertical
Combustion chamber type Direct injection
Valve position OHV
Diameter x stroke 123x155
Compression ratio 17.1 16.1 16.8
Comp. pressure(kg/cm2-rpm) 28-200
Average efficient comp.(kg/cm2) 9.27 13.08 14.21
Max. horse power(ps/rpm) 228/2,200 280/2,100 310/2,100 340/2,100
Max. torque(kg•m/rpm) 80/1,400 115/1,260 125/1,260 140/1,260
Firing order 1-5-3-6-2-4
Engine dimension(LxWxH) 1,317x747x1,015 1,317x847x1,064
Dry weight(kg) 872 909 910
Cycle 4
Piston Material AL
Comp. ring 2
Oil ring 1
Open BTDC 18° BTDC 18°
Close ABDC 34° ABDC 32°
Open BBDC 46° BBDC 70°
Close ATDC 14° ATDC 30°
Intake 0.3
Exhaust 0.3
Engine speed at no load 550~600
Lubricating Type Forced pressure type
Oil pump type Gear
Oil filter type Strainer
Oil capacity(M)20
Oil cooler type Water cooled
Intake
Exhaust
No. of piston ring
Valve clearance
(cold engine)
Lubricatring system
In. & Ex.
Valve
timing
E
n
g
i
n
e

- 5 -
Item DE12-228 DE12TI-280 DE12TI-310 DE12TIS
Turbocharger type - Exhaust gas driven
Intercooler type - Air cooled
Cooling type Forced water circulation
Coolant capacity 19(engine only)
Water pump type Centrifugal
Thermostat type Wax pellet
Fuel pump type Plunger
Fuel filter type Full flow
Fuel injection type Mechanical Electronic control
Type Inline
Timing BTDC 8° BTDC 12° BTDC 1.0°
Plunger Dia. 12
Cam lift(mm) 11 12 14
Nozzle mounting Flange
Nozzle type Multi hole
Orifice No 5
Dia.(mm) 0.29 0.33 0.29
Inj. pressure(kg/cm2) 220 130/220 163/224
Voltage(V) 24V
Type Electric
Voltage(V) - Amp(A) 22-120
Output(V-A) ----
Regulator ----
Type Reduction
Output(kW) 24V-6.0kW
Type
Air compression
Cooling
system
Engine
Fuel
system
Electric
system
Inj.
pump
system
Inj.
nozzle
Preheat
-ing
system
Alternator
Starter
Ignition

1.4. Engine performance curve
1.4.1. DE12
- 6 -
220
200
180
160
140
120
100
1000 1200 1400 1600 1800 2000 2200 2400
85
80
75
170
160
165
70
Performance criteria ISO 1585(SAE J1349)
Output(Max.) 235 ps/2,200 rpm
Torque(Max.) 81.5 kg.m/1,400 rpm
Fuel consumption ratio(min.) 160 g/ps.h
EQM1004I
Revolution(rpm)
Output(ps)
Torque(kg.m)Fuel consumption(g/ps.h)

- 7 -
1.4.2. DE12(’98 type)
220
200
180
160
140
120
100
1000 1200 1400 1600 1800 2000 2200 2400
80
75
70
165
160
155
Performance ISO 1585(SAE J1349)
Output(Max.) 228 ps/2,200 rpm
Torque(Max.) 80 kg.m/1,400 rpm
Fuel consumption ratio(min.) 155 g/ps.h
EQM1005I
Revolution(rpm)
Output(ps)
Torque(kg.m)Fuel consumption(g/ps.h)

- 8 -
1.4.3. DE12T
155
160
165
170
90
80
100
110
1 000 1200 1400 1600 1800 2000 2200 2400
120
150
180
210
240
270
300
Performance ISO 1585(SAE J1349)
Output(Max.) 300 ps/2,200 rpm
Torque(Max.) 110 kg.m/1,300 rpm
Fuel consumption ratio(min.) 155 g/ps.h
EQM1006I
Revolution(rpm)
Output(ps)
Torque(kg.m)
Fuel consumption(g/ps.h)

- 9 -
1.4.4. DE12TI
150
155
160
125
120
130
135
1 000 1200 1400 1600 1800 2000 2200 2400
160
190
220
250
280
310
340
Performance ISO 1585(SAE J1349)
Output(Max.) 340 ps/2,100 rpm
Torque(Max.) 135 kg.m/1,260 rpm
Fuel consumption ratio(min.) 147 g/ps.h
EQM1007I
Revolution(rpm)
Output(ps)
Torque(kg.m)
Fuel consumption(g/ps.h)

- 10 -
1.4.5. DE12TI(280 ps : ’98 type)
300
220
220
180
1000 1200 1600 1800 2000 2200 2400
145
150
155
115
105
95
1400
140
260
Performance ISO 1585(SAE J1349)
Output(Max.) 280 ps/2,100 rpm
Torque(Max.) 115 kg.m/1,260 rpm
Fuel consumption ratio(min.) 145 g/ps.h
EQM1008I
Revolution(rpm)
Output(ps)
Torque(kg.m)
Fuel consumption(g/ps.h)

- 11 -
1.4.6. DE12TI(310 ps : ’98 type)
320
125
115
105
155
150
145
280
240
200
160
1000 1200 1400 1600 1800 2000 2200 2400
Performance ISO 1585(SAE J1349)
Output(Max.) 310 ps/2,100 rpm
Torque(Max.) 125 kg.m/1,260 rpm
Fuel consumption ratio(min.) 145 g/ps.h
EQM1009I
Revolution(rpm)
Output(ps)
Torque(kg.m)
Fuel consumption(g/ps.h)

- 12 -
1.4.7. DE12TIS
400 300
100
0
200
ps kW
350
300
250
200
150
1200 120
1400
N.m
g/kW.h g/ps.h
ISO 1585 kg.m
140
1000
200
190
210 160
150
140
220
100
1000
EA2M1002
2000 22001800160014001200
Revolution(rpm)
Power output(ps)
Fuel consumption(g/ps.h) Torque(kg.m)
Performance ISO 1585(SAE J1349)
Output(Max.) 340 ps/2,100 rpm
Torque(Max.) 140 kg.m/1,260 rpm
Fuel consumption ratio(min.) 143 g/ps.h

1.5. Exterior view of engine
1.5.1. DE12- for Bus
- 13 -
17 19 18 13
4
67920
22
14 5 1 226 23
25 16 15 3 8
21 12 11 27
2410
1. Cylinder block
2. Flywheel housing
3. Breather
4. Oil filler pipe
5. Vibration damper
6. Flywheel
7. V-pulley
8. Cylinder head
9. Oil filter
10. Oil cooler
11. Oil pan
12. Oil dipstick
13. Cooling water pipe
14. Water pump
15. Exhaust manifold
16. Heat shield
17. Intake manifold
18. Intake stake
19. Injection pipe
20. Injection pump
21. Injection pump bracket
22. Fuel filter
23. Starter
24. Air heater
25. Air compressor
26. Mounting bracket
27. Power steering pump
EQM1010I

- 14 -
1.5.2. DE12- for Truck
18
24
7
610
15
2251285
EA2M1003
30 17938
22 294121321
16
272319 142620
11
1. Cylinder block
2. Flywheel housing
3. Breather
4. Oil filler pipe
5. Vibration damper
6. Flywheel
7. Idle pulley
8. Cylinder head
9. Cylinder head cover
10. Oil filter
11. Oil cooler
12. Oil pan
13. Oil dipstick
14. Cooling water pipe
15. Water pump
16. Cooling fan
17. Exhaust manifold
18. Intake manifold
19. Intake stake
20. Injection pipe
21. Injection pump
22. Injection pump bracket
23. Fuel filter
24. Alternator
25. Starter
26. Air heater
27. Air-conditioning compressor
28. Engine mounting bracket
29. Power steering pump
30. Air compressor

- 15 -
1.5.3. DE12T- for Bus
10 2016 18 13
4
621
23
111222 2897
25
26 17 19 315 8
14 527 124 2
1. Cylinder block
2. Flywheel housing
3. Breather
4. Oil filler pipe
5. Vibration damper
6. Flywheel
7. V-pulley
8. Cylinder head
9. Oil filter
10. Oil cooler
11. Oil pan
12. Oil dipstick
13. Cooling water pipe
14. Water pump
15. Exhaust manifold
16. Intake manifold
17. Heat shield
18. Intake stake
19. Turbocharger
20. Injection pipe
21. Injection pump
22. Injection pump bracket
23. Fuel filter
24. Starter
25. Air heater
26. Air compressor
27. Mounting bracket
28. Power steering pump
EQM1011I

- 16 -
1.5.4. DE12TI(340 ps)- for Bus
10 16 22 17 27 21
29
4
67923
25 28 20 18
14 30 2651 2
19 1538
24 12 3111
13
1. Cylinder block
2. Flywheel housing
3. Breather
4. Oil filler pipe
5. Vibration damper
6. Flywheel
7. V-pulley
8. Cylinder head
9. Oil filter
10. Oil cooler
11. Oil pan
12. Oil dipstick
13. Cooling water pipe
14. Water pump
15. Exhaust manifold
16. Intake manifold
17. Intake stake
18. Turbocharger
19. Air pipe, T/C-A/P
20. Air pipe, A/P-I/C
21. Air pipe, A/P-I/C
22. Injection pipe
23. Injection pump
24. Injection pump bracket
25. Fuel filter
26. Starter
27. Air heater
28. Air compressor
29. Alternator
30. Mounting bracket
28. Power steering pump
EQM1012I

- 17 -
1.5.5. DE12TI(280 ps : ’98 type)- for Bus
10
28
4
9722
24 27 19 18
14 29 2551 2
1538
12 11 30236
17 1321 26 2016
1. Cylinder block
2. Flywheel housing
3. Breather
4. Oil filler pipe
5. Vibration damper
6. Flywheel
7. V-pulley
8. Cylinder head
9. Oil filter
10. Oil cooler
11. Oil pan
12. Oil dipstick
13. Cooling water pipe
14. Water pump
15. Exhaust manifold
16. Intake manifold
17. Intake stake
18. Turbocharger
19. Air pipe, T/C-A/P
20. Air pipe, A/P-I/C
21. Injection pipe
22. Injection pump
23. Injection pump bracket
24. Fuel filter
25. Starter
26. Air heater
27. Air compressor
28. Alternator
29. Mounting bracket
30. Power steering pump
EQM1013I