Doosan DE12, De12, DE12T, DE12TI, DE12TIS User Manual

DE12, DE12T &

DE12TI & DE12TIS

DIESEL ENGINE

Shop Manual

65.99892-8030B

Daewoo reserves the right to improve our products in a continuing process to provide the best possible product to the market place. These improvements can be implemented at any time with no obligation to change materials on previously sold products. It is recommended that consumers periodically contact their distributors for recent documentation on purchased equipment.

This documentation may include attachments and optional equipment that is not available in your machine’s package. Please call your distributor for additional items that you may require.

Illustrations used throughout this manual are used only as a representation of the actual piece of equipment, and may vary from the actual item.

65.99892-8030B Shop Manual

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 purpose. 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, lowemission 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.

EA2M1001

<Figure. 1-1> OMEGA combustion bowl

- 1 -

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 performance, just from the time of starting off the vehicle but also to greatly reduce fuel consumption.

Compressed air outlet por

Turbine

Intake air

Exhaust gas outlet port

Waste gate

Compressor

Actuator

EQM1003I

Turbine port

<Figure 1-3> Turbochager

- 2 -

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
Bore B stroke-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)

Item

	Average efficient comp.(kg/cm2)
n	Max. horse power(ps/rpm)
	Max. torque(kg•m/rpm)
g	Firing order
i	Engine dimension(LxWxH)
	Dry weight(kg)
n	Cycle
	Piston Material
e			Comp. ring
	No. of piston ring
			Oil ring
		Intake	Open
	In. & Ex.		Close
	Valve
	timing	Exhaust	Open
			Close
	Valve clearance		Intake
	(cold engine)		Exhaust
		Engine speed at no load
	Lubricatring system	Lubricating Type
		Oil capacity(M)
		Oil pump type
		Oil filter type
		Oil cooler type
	Manufacturer
	Mounting location
	Starting type
	Engine type
	Cylinder(No. arrangement)
	Combustion chamber type
	Valve position
	Diameter x stroke
	Compression ratio
	Comp. pressure(kg/cm2-rpm)
E

DE12-228	DE12TI-280			DE12TI-310			DE12TIS
DHI
Under Seat
SELF
Diesel 4 Cycle	Turbocharged & Intercooled
In-line, vertical
Direct injection
OHV
123x155
17.1	16.1						16.8
28-200
9.27	13.08			14.21
228/2,200	280/2,100			310/2,100			340/2,100
80/1,400	115/1,260			125/1,260			140/1,260
1-5-3-6-2-4
1,317x747x1,015	1,317x847x1,064
872	909			910
4
AL
2
1
BTDC 18°							BTDC 18°
ABDC 34°							ABDC 32°
BBDC 46°							BBDC 70°
ATDC 14°							ATDC 30°
0.3
0.3
550~600
Forced pressure type

Gear

Strainer

20

Water cooled

- 4 -

Item

DE12-228

DE12TI-280

DE12TI-310

DE12TIS

Turbocharger type

-

Exhaust gas driven

Intercooler type

-

Air cooled

Engine

Cooling type

Forced water circulation

Cooling

Coolant capacity

19(engine only)

system

Water pump type

Centrifugal

Thermostat type

Wax pellet

Fuel pump type

Plunger

Fuel filter type

Full flow

Fuel injection type

Mechanical

Electronic control

Inj.

Type

Inline

Timing

BTDC 8°

BTDC 12°

BTDC 1.0°

pump

Fuel

system

Plunger Dia.

12

system

Cam lift(mm)

11

12

14

Nozzle mounting

Flange

Inj.

Nozzle type

Multi hole

No

5

nozzle

Orifice

Dia.(mm)

0.29

0.33

0.29

Inj. pressure(kg/cm2)

220

130/220

163/224

Voltage(V)

24V

Preheat

Type

Electric

-ing

system

Voltage(V) - Amp(A)

22-120

Electric

Alternator

Output(V-A)

-

-

-

-

system

Regulator

-

-

-

-

Starter

Type

Reduction

Output(kW)

24V-6.0kW

Ignition

Type

Air compression

- 5 -

1.4. Engine performance curve

1.4.1. DE12

Output(ps)

220

200

180

160

140

120

100

85
80	m)
	.
75	Torque(kg
70

	h)
	.
170	consumption(g/ps
165
160	Fuel

1000

1200

1400

1600

1800

2000

2200

2400

Revolution(rpm)

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

- 6 -

1.4.2. DE12(’98 type)

Output(ps)

220

200

180

160

140

120

100

1000

1200

1400

1600

1800

2000

2200

2400

Revolution(rpm)

80
75	m)
	.
70	Torque(kg

	h)
	.
155	consumption(g/ps
165
160
	Fuel

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

- 7 -

1.4.3. DE12T

Output(ps)

300

270

240

210

180

150

120

110
100	m)
	.
90	Torque(kg
80

	h)
	.
160	consumption(g/ps
170
165
155	Fuel

1 000

1200

1400

1600

1800

2000

2200

2400

Revolution(rpm)

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

- 8 -

1.4.4. DE12TI

Output(ps)

340

310

280

250

220

190

160

135
130	m)
	.
125	Torque(kg
120

	h)
	.
155	consumption(g/ps
160
150	Fuel

1 000

1200

1400

1600

1800

2000

2200

2400

Revolution(rpm)

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

- 9 -

1.4.5. DE12TI(280 ps : ’98 type)

Output(ps)

300

220

260

220

180

140

115
105	m)
	.
95	Torque(kg

									h)
									.
								155	consumption(g/ps
								150
								145	Fuel
1000	1200	1400	1600	1800	2000	2200	2400

Revolution(rpm)

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

- 10 -

1.4.6. DE12TI(310 ps : ’98 type)

Output(ps)

320

280

240

200

160

1000

1200

1400

1600

1800

2000

2200

2400

Revolution(rpm)

125
115	m)
	.
105	Torque(kg

	h)
	.
155	consumption(g/ps
150
145	Fuel

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

- 11 -

1.4.7. DE12TIS

Power output(ps)

ps	kW	ISO 1585	kg.m
		N.m
		1400	140
		1200	120	m)
				.
400	300			Torque(kg
		1000	100
350

300

200

250

200
150									h)
100
								.
							150		consumption(g/ps
						g/kW.h g/ps.h
						220	160
						210
						200			Fuel
						190	140
0
	1200	1400	1600	1800	2000	2200
1000

Revolution(rpm)

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

EA2M1002

- 12 -

1.5. Exterior view of engine

1.5.1. DE12for Bus

10

17

19

18

24

13

						4	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
6	9	20	21	12	11	27 7	10.	Oil cooler
							11.	Oil pan
							12.	Oil dipstick
							13.	Cooling water pipe
							14.	Water pump
22	25	16		15	3	8	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

14

5

26

1

23

2

EQM1010I

- 13 -

1.5.2. DE12for Truck

18

20

26

19

23

14

27

24

11

7

16

6

10

22

21 13

12

4

29

15

30

9

17

3

8

5

28

1

25

2

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

EA2M1003

- 14 -

1.5.3. DE12Tfor Bus

10

16

20

18

25

13

4

6

9

21

22

12

11

28

7

23

26

17

19

3

15

8

14

5

27

1

24

2

EQM1011I

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

- 15 -

1.5.4. DE12TI(340 ps)- for Bus

10

16

22

17

27

13

21

29

4

6	9	23		24	12	11	31	7
25		28	20	18	19	3	15	8

14

5

30

1

26

2

EQM1012I

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

- 16 -

1.5.5. DE12TI(280 ps : ’98 type)- for Bus

10

16

21

17

26

13

20

28

4

6	9	22	23	12	11	30	7
24	27	19		18	3	15	8

14

5

29

1

25

2

EQM1013I

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

- 17 -

1.5.6. DE12TI(310 ps : ’98 type)- for Bus

10

16

22

17

27

13

21

29

4

6	9	23		24	12	11	31	7
25		28	20	18	19	3	15	8

14

5

30

1

26

2

EQM1014I

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

31.Power steering pump

- 18 -

1.5.7. DE12TI - for Truck

11

27

19

24

30

20

14

28

31

7

16

2		10	26	25 13		12	4	33
15	23	34	22	17	9	3		18	8

5

32

1

21

29

6

EA2M1004

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.Heat screen

19.Intake manifold

20.Intake stake

21.Turbocharger

22.Air pipe, A/C-T/C

23.Air pipe, T/C-I/C

24.Injection pipe

25.Injection pump

26.Injection pump bracket

27.Fuel filter

28.Alternator

29.Starter

30.Air heater

31.Air-conditioning compressor

32.Engine mounting bracket

33.Power steering pump

34.Air compressor

- 19 -

1.5.8. DE12TIS - for Bus

18 24 32 19 26 27 28 14 23 30

11

4

6

10

12

29

25 13

12

34

15

35

22

9

21

16

3

17

8

7

5

33

1

20

31

2

EA2M1005

1.Cylinder block

2.Flywheel housing

3.Breather

4.Oil filler pipe

5.Vibration damper

6.Flywheel

7.Crank shaft 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.Exhaust manifold

17.Heat screen

18.Intake manifold

19.Intake stake

20.Turbocharger

21.Air pipe, A/C-T/C

22.Air pipe, T/C-A/P

23.Air pipe, A/P-I/C

24.Injection pipe

25.Injection pump

26.Pick-up sensor

27.Prestroke actuator sensor

28.Rack sensor

29.Injection pump bracket

30.Fuel filter

31.Starter

32.Air heater

33.Engine mounting bracket

34.Power steering pump

35.Air compressor

- 20 -

1.5.9. DE12TIS - for Truck

30 19 24 33 20 26 27 28 14 34

31

11

7

16

2

10

29

25 13

12

4

36

15

23

37

9

22

17

18

3

8

5

35

1

21

32

6

EA2M1006

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.Heat screen

19.Intake manifold

20.Intake stake

21.Turbocharger

22.Air pipe, A/C-T/C

23.Air pipe, T/C-I/C

24.Injection pipe

25.Injection pump

26.Pick-up sensor

27.Prestroke actuator sensor

28.Rack sensor

29.Injection pump bracket

30.Fuel filter

31.Alternator

32.Starter

33.Air heater

34.Air-conditioning compressor

35.Engine mounting bracket

36.Power steering pump

37.Air compressor

- 21 -

2. Major maintenance

2.1. Preventive maintenance

2.1.1.Cooling water

1)Check the coolant level of the radiator by removing the radiator filler cap, and add coolant if necessary.

2)Check the pressure valve opening pressure using a radiator cap tester. Replace the radiator filler cap assembly if the measured value does not reach the specified limit.

3)When injecting antifreeze solution, first drain out the old coolant from the cylinder block and radiator, and then clean them with cleaning solution.

4)Be sure to mix soft water with antifreeze solution .

5)A proportion of antifreeze is represented as the ratio of antifreeze in volume, and antifreeze must be added according to each ambient temperature as described below:

Antifreeze solution(%)	Freezing point(C)
20	-10
27	-15
33	-20
40	-25
44	-30
50	-40

CAUTION

If you add antifreeze in excess of 50% in volume, the engine may be overheated. Avoid this.

As the individual freezing points corresponding to the above proportions of antifreeze are subject to change slightly according to the kind of antifreeze, you must follow the specifications provided by the antifreeze manufacturer.

6)When the ratio of antifreeze in the mixture decreases new coolant should be added to make up for the loss in old coolant resulting from engine operation, check the mix ratio with every replenishment of coolant, and top up as necessary.

7)To prevent corrosion or air bubbles in the coolant path, be sure to add a specific additive, i.e. corrosion inhibitor, to the coolant.

•Type : DAC65L

•Mix ratio : 1.5M of inhibitor to 50M of coolant

(Namely, add corrosion inhibitor amounting to 3% of water capacity.)

8) Add antifreeze of at least 5% in volume to prevent possible engine corrosion in hot weather.

- 22 -

2.1.2.Fan belt

1)Use a fan belt of specified dimensions, and replace if damaged, frayed, or deteriorated.

2)Check the fan belt for belt tension. If belt tension is lower than the specified limit, adjust the tension by relocating the alternator and air conditioner. (Specified deflection: 10~15mm when pressed down with thumb)

2.1.3.Engine oil

1)Check oil level using the oil dipstick and replenish if necessary.

2)Check the oil level with the vehicle stationary on a level ground, engine cooled. The oil level must be between MAX and MIN lines on the stick.

3)Engine oil should be changed at the specified intervals. Oil in the oil filter also should be changed simultaneously.

(First oil change : 1,000km running)

• Suggested engines oils

Engine Model	SAE NO.	API NO
DE12, DE12T,DE12TI	15W40	CD grade or above
DE12TIS	15W40	CG grade

2.1.4.Oil filter

1)Check for oil pressure and oil leaks, and repair or replace the oil filter if necessary.

2)Change the oil filter element simultaneously at every replacement of engine oil.

2.1.5.Fuel filter

1)Drain water in cartridge with losen the cock under filter from time to time.

2)The fuel filter should be replaced at every 20,000km

2.1.6.Air cleaner

1)Replace any deformed or broken element or cracked air cleaner.

2)Clean or replace the element at regular intervals

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2.1.7.Valve clearance

1)Turn the crank shaft so that the piston in No. 1 cylinder reaches the TDC on compression

stroke, then adjust the valve clearance.

2)After releasing the lock nut for the rocker arm adjusting screw, insert a feeler gauge of specified thickness into the clearance between the rocker arm and valve stem, and adjust the clearance with the adjusting screw. Fully tighten the lock nut when a correct adjustment is obtained.

3)Carry out the same adjusting operation according to the firing order(1-5-3-6-2-4) (Valve clearance(with engine cooled): 0.30mm for both intake and exhaust)

2.1.8.Cylinder compression pressure

1)Stop the engine after warming up, then remove the nozzle holder assembly.

2)Install a special tool(gauge adapter) in nozzle holder hole and mount the compression gauge in position of the nozzle holder.

Standard	28 kg/cm2 over
Limit	24 kg/cm2 or less
Difference between each cylinder	L10% or less

3)Cut off fuel circulation, rotate the starter, then measure compression pressure in each cylinder.

6Testing conditions: Coolant temperature 20C, Engine speed, 200 rpm (10 turns)

2.1.9.Injection nozzle

1)Assemble a nozzle to a nozzle tester.

2)Check injection pressure, and adjust the nozzle using the adjusting shim if the pressure does not meet the specified limit.

3)Check nozzle spray patterns and replace if damaged.

Normal

Abnormal

Abnormal

EFM1006I

<Figure 2-1> Nozzle spray patterns

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2.1.10.Fuel injection pump

1)Check the fuel injection pump housing for cracks or breaks, and replace if damaged.

2)Check and see if the lead seal for idling control and speed control levers have not been removed.

2.1.11.Battery

1)Check the battery for damage or leaking of battery fluid(electrolyte) from cracks on the battery. Replace the battery if damaged.

2)Check battery fluid level and add distilled water if necessary.

3)Measure the specific gravity of the electrolyte in the battery. Recharge the battery if the hydrometer readings are lower than the specified limit(1.12~1.28)

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2.2. Diagnostics and trouble shooting for the engine

2.2.1. Diagnostics

1. Engine won’t start

Starter does not turn

Starter

turns but engine does not start

Check battery fluid and specific gravity

Engine

Fuel

Normal

Too low

Check air cleaner

Check fuel level

Replenish or recharge

Normal

Fouled

Normal

No fuel

Check cable connections

Replace or clean element

Replenish

Normal

Replenish or recharge

Check compression pressure

Check fuel injection

Check starter s/w

Normal

Too low

Normal

No fuel injection

Normal

Replenish or recharge

Retighten or replace

Air bleeding and re-start

Check starter relay

Check other parts

Check injection timing

Normal

Replace

Check valve clearance

Normal

Adjust

Check magnetic s/w

Normal

Adjust

Check injection nozzle(injection

pressure, injection condition, etc.)

Normal

Replenish or recharge

Check cylinder head gasket

Normal

Repair or replace

Disassemble and check starter motor

Normal

Replace

Disassemble and check

Overhaul the engine

injection pump

(valve assembly, cylinder

liner, piston, etc.)

Check fuel feed pump for function

Normal

Check feed pump valve and strainer

Air in the fuel

Disassemble and check injection pump

Normal

Clean or replace

Retighten the joint and/or replace gasket

Check fuel filter

Air bleeding

Dirty element and/or overflow valve faulty

Continuous entry of air in fuel system

Replace

Disassemble and check feed pump

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2. Engine overheating

Cooling system

Fuel system

Operating conditions

1. Overload

2. Clogged radiator core

3. Continued overrunning

Check coolant level

Check fuel quality

Normal

Too low

Bad

Check fan belt for tension, wear, or breaks

Clean or replace with the specified fuel

Normal

Repair or replace

Check radiator cap

Replenish

Check water pump

Normal

Replace

External

Internal

Check thermostat

Retighten or repair

Overhaul engine

Normal

Replace

Excessive fuel rate

Check radiator

Check injection nozzles

Normal

Damaged

Normal

Abnormal

Repair or replace

Repair or replace

Clean coolant path

Adjust or repair injection pump

Check water pump

Normal			Repair or replace

Overhaul the engine

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