Daewoo DE12, De12, DE12T, DE12TI, DE12TIS Service Manual

...

DE12, DE12T &

DE12TI & DE12TIS

DIESEL ENGINE

Shop Manual

65.99892-8030B

Daewoo reserves the righ t to improve our products in a continuing proc ess to provide the best possible product to the mar ket place. These improvements can be implem ented at any time with no obligation t o 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. 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 performance, just from the time of starting off the vehicle but also to greatly reduce fuel consumption.

- 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

BoreB 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)

- 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

- 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

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

- 7 -

1.4.2. DE12(’98 type)

220

200

180

160

140

120

100

1000 1200 1400 1600 1800 2000 2200 2400

80 75

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

- 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

Fuel consumption(g/ps

- 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

Fuel consumption(g/ps

- 10 -

1.4.5. DE12TI(280 ps : ’98 type)

300

220

180

1000 1200 1600 1800 2000 2200 2400

145

150

155

115 105

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

Fuel consumption(g/ps

- 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

Fuel consumption(g/ps

- 12 -

1.4.7. DE12TIS

400

300

100

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

Torque(kg

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

67920

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

610

2251285

EA2M1003

30 17938

22 294121321

272319 142620

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

621

111222 2897

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

67923

25 28 20 18

14 30 2651 2

19 1538

24 12 3111

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

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

- 18 -

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

10 16 22 17 27 21

67923

25 28 20 18

14 30 2651 2

19 1538

24 12 3111

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

EQM1014I

- 19 -

1.5.7. DE12TI - for Truck

EA2M1004

11 14 28 3119 24 30 20

15 23 34 22 17 1893 8

2134

5 32 1 29 621

3312252610

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

- 20 -

1.5.8. DE12TIS - for Bus

EA2M1005

71 233 31205

1735 22 21 16938

10 2912 12 341325

24 32 19 1426 23 3027 28

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

- 21 -

1.5.9. DE12TIS - for Truck

20 26 27 28 34332419 14

2410

56135 3221

923 37 22 17 18 3 8

29 25 13 12 36

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

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:

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.

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.

Antifreeze solution(%) Freezing point(C)

20 -10 27 -15 33 -20 40 -25 44 -30 50 -40

- 22 -

CAUTION

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

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

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

- 23 -

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.

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

6 Testing 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.

Standard 28 kg/cm2over

Limit 24 kg/cm2or less

Difference between each cylinder L10% or less

- 24 -

Normal Abnormal Abnormal

<Figure 2-1> Nozzle spray patterns

EFM1006I

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)

- 25 -

2.2. Diagnostics and trouble shooting for the engine

2.2.1. Diagnostics

- 26 -

1. Engine won’t start

Starter does not turn Starter turns but engine does not start

Check battery fluid and specific gravity Engine Fuel

Too low Check air cleaner Check fuel level

Replenish or recharge

Check cable connections

Check starter s/w

Check starter relay

Check magnetic s/w

Disassemble and check starter motor

Disassemble and check injection pump

Normal

Fouled

Replace or clean element

Check compression pressure

Check other parts

Check cylinder head gasket

Overhaul the engine

(valve assembly, cylinder

liner, piston, etc.)

Check fuel feed pump for function

Check feed pump valve and strainer Air in the fuel

Retighten the joint and/or replace gasket

Air bleeding

Continuous entry of air in fuel system

Disassemble and check feed pump

Dirty element and/or overflow valve faulty

Check fuel filter

Replace

Normal

Too low

Retighten or replace

Check valve clearance

Normal

No fuel

Replenish

Check fuel injection

Normal

AdjustNormal

Repair or replaceNormal

No fuel injection

Air bleeding and re-start

Check injection timing

Check injection nozzle(injection pressure, injection condition, etc.)

Disassemble and check injection pump

Normal

AdjustNormal

ReplaceNormal

Clean or replaceNormal

Normal

Replenish or recharge

Normal

Replenish or recharge

Normal

ReplaceNormal

Replenish or recharge

Normal

Overhaul the engine

- 27 -

2. Engine overheating

Cooling system Fuel system

Check coolant level Check fuel quality

Operating conditions

1. Overload

2. Clogged radiator core

3. Continued overrunning

Too lowNormal Bad

Repair or replaceNormal

ReplaceNormal

Damaged

Repair or replace

Normal

Check fan belt for tension, wear, or breaks Clean or replace with the specified fuel

Check radiator cap Replenish

Check thermostat

Check radiator

Repair or replaceNormal

Check water pump

InternalExternal

Overhaul engineRetighten or repair

Clean coolant path

Abnormal

Repair or replace

Normal

Check injection nozzles

Excessive fuel rate

Adjust or repair injection pump

+ 135 hidden pages