Isuzu 4JA1, 4JH1 Workshop Manual

WORKSHOP MANUAL

2011MY TF SERIES

ENGINE

4JA1/4JH1 MODELS

SECTION 6

Isuzu Motors Limited

E-Solutions &

Service Marketing Dept.

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TROUBLESHOOTING 6 – 1

SECTION 6

TROUBLESHOOTING

TABLE OF CONTENTS

PAGE PAGE

BASIC INSPECTION PROCEDURE....6– 2

1. HARD STARTING............................6– 3

1-1.Starter Motor Inoperative ..........6– 3

1-2. Starter Motor Operates But

Engine Does Not Turn Over ...........6– 3

1-3. Engine Turns Over But Does

Not Start Engine..............................6– 4

2. UNSTABLE IDLING.........................6– 5

3. INSUFFICIENT POWER ..................6– 6

4. EXCESSIVE FUEL

CONSUMPTION..................................6– 7

5. EXCESSIVE OIL CONSUMPTION ..6– 8

6. OVERHEATING ...............................6– 9

7. WHITE EXHAUST SMOKE..............6– 9

8. DARK EXHAUST SMOKE...............6– 10

9. OIL PRESSURE DOES NOT RISE..6– 11

10. ABNORMAL ENGINE NOISE........6– 12

10-1. Engine Knocking ....................6– 12

10-2. Gas Leakage Noise.................6– 12

10-3. Continuous Noise ...................6– 13

10-4. Slapping Noise........................6– 13

10-5. Excessive Turbocharger

Noise ................................................6– 14

11. ROTATING PART WEAR OF

TURBOCHARGER..............................6– 14

12. OIL LEAKAGE FROM

TURBOCHRGER ................................6– 15

13. INSUFFICIENT ACCELERATION AND/OR LACK OF POWER DUE

TO TURBOCHARGER........................6– 15

14. BATTERY CHARGING AND

NOISE PROBLEM ..............................6– 16

14-1. Battery No Charging...............6– 16

14-2. Battery Overcharging .............6– 16

14-3. Battery Under Charging .........6– 17

14-4. Battery Unstable Charging

Current.............................................6– 17

14-5. Charging System Noise .........6– 18

15. STARTER MOTOR PROBLEM .....6– 19

15-1. Starter Motor Pinion Engages to Ring Gear But Engine Does

Not Turn Over..................................6– 19

15-2. Incorrect Pinion And Ring

Gear Engagement ...........................6– 19

15-3. Starter Motor Continues To Run After The Starter Switch Is

Turned Off........................................6– 20

15-4. Excessive Commutator

Sparking ..........................................6– 20

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6 – 2 TROUBLESHOOTING

Basic Inspection Procedure

Follow the under inspection procedure, when the problem vehicle comes workshop.

Step Inspection point Inspection result YES NO

1 Check the check engine lamp Is the check engine lamp turn

ON ?

Go to section

6E “On Board

Diagnostic

(OBD) System

Check" Go to Step 2

2 The battery fluid level and the

gravity

Was the problem found? Re-charge the

battery or

replace the

battery Go to Step 3

3 The engine coolant capacity Was the problem found? Replenish the

engine coolant Go to Step 4

4 The engine oil level Was the problem found? Replenish the

engine oil Go to Step 5

5 The air cleaner element Was the problem found? Clean or

replace Go to Step 6

6 The piping fixing condition (oil,

vacuum and fuel piping)

Was the problem found? Return normal

condition Go to Step 7

7 The drive belt tension and break Was the problem found? Re-adjust the

tension or

replace Go to Step 8

8 Go to section 6E “On Board

Diagnostic (OBD) System Check”

Was the problem found?

Verify repair Go to Step 9

9 Go to mechanical

troubleshooting chart

Was the problem found?

Verify repair —

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TROUBLESHOOTING 6 – 3

1. Hard Starting

Inspect the following items before diagnosis.

1. The battery conditions. The terminal connection condition. The battery charge condition or battery power weakness.

2. The fan belt loosen or broken.

3. The main fuse condition (open or not).

4. Fuel quantity level.

1–1 Starter motor inoperative

Step Action Value(s) Yes No

1 Check the starter switch.

Does the starter switch work?

—

Go to Step 2

Repair or

replace the

starter switch

2 Check the starter relay.

Does the starter relay work?

—

Go to Step 3

Repair or

replace the

starter relay

3 Check the magnetic switch.

Does the magnetic switch work?

—

Go to Step 4

Repair or

replace the

magnetic

switch

4 Check the pinion gear condition on the starter motor.

Was the condition normal?

—

Go to Step 5

Replace the

pinion gear

5 Check the brush wear or brush spring weakness.

Was the condition normal?

—

Replace the

starter motor

assembly

Repair or

replace the

brush or brush

spring

1-2 Starter motor operates but engine does not turn over

Step Action Value(s) Yes No

1 Check the engine internal seizure.

Was the engine seized?

—

Repair or

replace seized

parts

Check other

DTC by Tech

2 and go to

indicated DTC

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6 – 4 TROUBLESHOOTING

1-3 Engine turn over but does not start engine

Incase of the fuel not being delivered to the injection pump

Step Action Value(s) Yes No

1 Check clogged, damaged the fuel piping or the

connector loosen. Was any problem found?

—

Repair replace

problem parts. Go to Step 2

2 Was the over flow valve on the fuel filter closed? — Repair replace

the over flow

valve Go to Step 3

3 Was the fuel filter element clogged? — Replace the

fuel filter

element Go to Step 4

4 Was the fuel line air bled? — Go to Step 5 Bleed the air

5 Are any DTC stored? — Go to indicated

DTC Solved

Incase of the fuel is being delivered to the injection pump

Step Action Value(s) Yes No

1 Was the water contain in the fuel? — Replace the

fuel Go to Step 2

2 Was the fuel line air bled? — Go to Step 3 Bleed the air

3 Was the injection spray condition complete? —

Go to Step 4

Replace the

injection nozzle

4 Was the injection nozzle injection starting pressure

OK?

(See below)

Go to Step 5

Replace the

injection nozzle

5 Was the injection nozzle sticking? — Replace the

injection nozzle Go to Step 6

6 Are any DTC stored? — Go to indicated

DTC Solved

Injection nozzle opening pressure 1st = 19.5 MPa (199 kg/cm

, 2828 psi)

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TROUBLESHOOTING 6 – 5

2. Unstable Idling

Step Action Value(s) Yes No

1 Was the fuel line air bled completely? — Go to Step 3 Bleed the air

2 Was the fuel line leakage or blockage found? — Repair or

replace relation

parts. Go to Step 4

3 Was the water contained in the fuel? — Replace the

fuel Go to Step 5

4 Was the fuel filter element clogged? — Replace the

fuel filter

element Go to Step 6

5 Was the injection starting pressure or the injection

spray condition OK?

(See below)

Go to Step 7

Replace the

injection nozzle

6 Was the injection nozzle sticking? See Step 6 Replace the

injection nozzle Go to Step 8

7 Check the throttle valve condition.

Was the idling port clogged in the throttle valve?

— Repair or

replace the

throttle valve Go to Step 9

8 Was the valve clearance improper adjusted? 0.4 mm

(0.016 in)

both intake

and exhaust

valves

Adjust the

valve clearance Go to Step 10

9 Was the compression pressure OK? 3.0MPa (31.0

kg/cm

, 441

psi) at

200rpm

Go to Step 11

Readjust the

valve clearance

or replace the

cylinder head

gasket or cylinder liner or piston or piston

ring or valve

and valve seat

10 Are any DTC stored? — Go to indicated

DTC Solved

Injection nozzle opening pressure 1st = 19.5 MPa (199 kg/cm

, 2828 psi)

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6 – 6 TROUBLESHOOTING

3. Insufficient Power

Step Action Value(s) Yes No

1 Was the air cleaner element condition OK? (Clogged

or not)

—

Go to Step 2

Clean or

replace the air

cleaner

element.

2 Was the intake air leakage found from intake

system?

— Repair or

replace the

intake air

system. Go to Step 3

3 Was the fuel filter element condition OK? (Clogged

or not)

—

Go to Step 4

Clean or

replace the fuel

filter element.

4 Check the fuel injection pipes.

Does the injection pipes have obstruction or any damage?

— Repair or

replace the fuel

injection pipes. Go to Step 5

5 Was the water contained in the fuel? — Replace the

fuel Go to Step 6

6 Was the injection nozzle pressure or spray pattern

normal?

—

Go to Step 7

Readjust the

injection nozzle

pressure or

replace the

nozzle.

7 Was the compression pressure OK? 3.0 MPa

(31.0 kg/cm

441 psi) at

200 rpm

Go to Step 8

Readjust the

valve clearance

or replace the

cylinder head

gasket or cylinder liner or piston or piston

ring or valve

and valve seat

8 Was the exhaust pipe clogged? — Repair or

replace the

exhaust pipe. Go to Step 9

9 Was the exhaust gas leakage found from exhaust

system?

— Repair or

replace the

exhaust system. Go to Step 10

10 Was the waste gate control actuator hose broken or

cracked?

— Replace the

hose. Go to Step 11

11 Was the waste gate working completely? —

Go to Step 12

Replace the

turbocharger

assembly.

12 Was turbocharger working completely? —

Go to Step 13

Replace the

turbocharger

assembly.

13 Are any DTC stored? — Go to indicated

DTC Solved

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TROUBLESHOOTING 6 – 7

4. Excessive Fuel Consumption

Step Action Value(s) Yes No

1 Was the air cleaner element clogged? — Clean or

replace the air

cleaner

element. Go to Step 2

2 Was the air leakage found from the air intake side of

the turbocharger?

— Repair or

replace the air

intake side of

the

turbocharger. Go to Step 3

3 Was the turbocharger working completely? —

Go to Step 4

Replace the

turbocharger

4 Was there the fuel leakage? — Repair or

replace the fuel

leakage part. Go to Step 5

5 Was the compression pressure OK? 3.0 MPa

(31.0 kg/cm

441 psi) at

200 rpm

Go to Step 6

Readjust the

valve clearance

or replace the

cylinder head

gasket or cylinder liner or piston or piston

ring or valve

and valve seat

6 Was the injection nozzle pressure or spray pattern

normal?

—

Go to Step 7

Replace the

injection nozzle

7 Are any DTC stored? — Go to indicated

DTC Solved

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6 – 8 TROUBLESHOOTING

5. Excessive Oil Consumption

Step Action Value(s) Yes No

1 Does the air cleaner element conditon OK? (Clogged

or not)

—

Go to Step 2

Clean or

replace the air

cleaner

element

2 Does PCV (Positive Crankcase Ventilation) Valve

has problem?

— Repair or

replace the

relation parts. Go to Step 3

3 Was the oil pressure value more than normal value? Less than

588 kPa (6.0

kg/cm

psi)

Repair or

replace the oil

relief valve Go to Step 4

4 Inspect the front and rear crankshaft oil seal.

Was the oil leakage found?

—

Replace the

failure part. Go to Step 5

5 Was the oil leakage found from any gasket? — Replace the

wrong gasket Go to Step 6

6 Inspect the valve stem seal, the valve stem and the

valve guide for worn. Were any worn found?

—

Replace the

worn part. Go to Step 7

7 Was the oil leakage found from the turbocharger oil

seal?

— Replace the oil

seal. Go to Step 8

8 Was the oil drain pipe of the turbocharger restricted? — Repair or

replace the oil

drain pipe. Go to Step 9

9 Was the oil drain passage in the turbocharger center

housing restricted?

— Clean the

center housing Go to Step 10

10 Does turbine wheel has any impact damage? — Replace the

turbocharger Go to Step 11

11 Are any DTC stored? — Go to indicated

DTC Solved

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TROUBLESHOOTING 6 – 9

6. Overheating

Step Action Value(s) Yes No

1 Was the engine coolant level OK? —

Go to Step 2

Replenish the

coolant

2 Was the water leakage or the radiator restriction

found? (Include radiator cap)

— Repair or

replace the

leakage part. Go to Step 3

3 Was the fan belt slippage found? — Tension or

replace the fan

belt. Go to Step 4

4 Was the fan clutch working completely? —

Go to Step 5

Replace the fan

clutch

assembly.

5 Was the oil leakage found from fan clutch? — Replace the fan

clutch

assembly Go to Step 6

6 Was the thermostat working normally? —

Go to Step 7

Replace the

thermostat.

7 Was the water pump working OK? —

Go to Step 8

Replace the

water pump

assembly.

8 Was the restriction by the foreign materials in the

cooling system found? For example, clog the water hose between the cylinder body and radiator etc..

— Clean or

replace the

clog part. Go to Step 9

9 Was the water leakage found from the sealing cap

on the cylinder body?

— Replace the

sealing cap or

replace the

cylinder body. Go to Step 10

10 Are any DTC stored? — Go to indicated

DTC. Solved

7. White Exhaust Smoke

Step Action Value(s) Yes No

1 Was the compression pressure OK? 3.0 MPa

(31.0 kg/cm

441 psi) at

200 rpm

Go to Step 2

Readjust the

valve clearance

or replace the

cylinder head

gasket or cylinder liner or piston or piston

ring or valve

and relation

parts.

2 Was the PCV (Positive Crankcase Ventilation) valve

working completely?

—

Go to Step 3

Repair or

replace the PCV valve.

3 Was the turbocharger working completely? —

Go to Step 4

Replace the

turbocharger.

4 Are any DTC stored? — Go to indicated

DTC Solved

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6 – 10 TROUBLESHOOTING

8. Dark Exhaust Smoke

Step Action Value(s) Yes No

1 Was the air cleaner element normal condition? —

Go to Step 2

Clean or

replace the air

cleaner

element

2 Was the EGR valve sticking? — Replace the

EGR valve Go to Step 3

3 Was the injection nozzle pressure or the injection

spray pattern OK?

—

Go to Step 4

Replace the

injection nozzle

4 Was the oil leakage found from the turbocharger oil

seal?

— Replace the oil

seal Go to Step 5

5 Was the oil drain pipe of the turbocharger restricted? — Repair or

replace the oil

drain pipe Go to Step 6

6 Was restricted the oil drain passage in the

turbocharger center housing restricted?

— Clean the

center housing Go to Step 7

7 Does turbine wheel has any impact damage? — Replace the

turbocharger Go to Step 8

8 Does PCV (Positive Crankcase Ventilation) Valve

has problem?

— Repair or

replace the

relation parts Go to Step 9

9 Are any DTC stored? — Go to indicated

DTC Solved

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TROUBLESHOOTING 6 – 11

9. Oil Pressure Does Not Rise

Step Action Value(s) Yes No

1 Was the oil pressure warning lamp working OK? —

Go to Step 2

Replace the oil

pressure

warning lamp

2 Does the oil filter element clog? — Replace the oil

filter element Go to Step 3

3 Does the relief valve open? — Repair or

replace the

relief valve Go to Step 4

4 Does the oil strainer clog? — Clean or

replace the oil

strainer Go to Step 5

5 Was the oil pump working OK? (The pump related

parts worn etc.)

—

Go to Step 6

Repair or

replace the oil

pump.

6 Was the rocker arm and/or relation parts worn? — Replace the

rocker arm

and/or relation

parts Go to Step 7

7 Was the camshaft and/or relation parts worn? — Replace the

camshaft

and/or relation

parts Go to Step 8

8 Was the crankshaft and/or relation parts worn? — Replace the

crankshaft

and/or relation

parts Go to Step 9

9 Are any DTC stored? — Go to indicated

DTC Solved

Table of pressure unit

Pressure kPa (kg/cm

) 100

(1.0)

980

(10.0)

Resistance ohm 81 30

Electric current A 63.5 106.7

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6 – 12 TROUBLESHOOTING

10. Abnormal Engine Noise

10–1 Engine knocking

Step Action Value(s) Yes No

1 Was the injection nozzle pressure or injection spray

pattern OK?

—

Go to Step 2

Replace the

injection nozzle

2 Was the compression pressure OK? 3.0 MPa

(31.0 kg/cm

441 psi) at

200 rpm Go to Step 3

Replace the

cylinder head

gasket or

piston ring

3 Are any DTC stored? — Go to indicated

DTC Solved

10–2 Gas leakage noise

Step Action Value(s) Yes No

1 Was the exhaust pipe loose or broken? — Retighten or

replace the

exhaust pipe Go to Step 2

2 Was the exhaust manifold loose? —

Retighten or

replace the

exhaust

manifold. Or

replace the

exhaust

manifold gasket Go to Step 3

3 Was the injection nozzle loose? — Retighten or

replace the

injection nozzle

fixing bolt Go to Step 4

4 Was the cylinder head gasket broken? — Replace the

cylinder head

gasket Go to Step 5

5 Are any DTC stored? — Go to indicated

DTC Solved

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TROUBLESHOOTING 6 – 13

10–3 Continuous noise

Step Action Value(s) Yes No

1 Was the fan belt tension OK? 9 – 13 mm

(0.35 – 0.51

in)

Go to Step 2

Adjust the fan

belt tension.

2 Was the cooling fan loose? — Tighten the

cooling fan Go to Step 3

3 Was noise coming from the generator? — Repair or

replace the

generator

and/or the

vacuum pump Go to Step 4

4 Was noise coming from the water pump? — Replace the

water pump Go to Step 5

5 Was noise coming from the cylinder head cover? — Readjust the

valve

clearance. Go to Step 6

6 Are any DTC stored? — Go to indicated

DTC Solved

10-4 Slapping noise

Step Action Value(s) Yes No

1 Was noise coming from the cylinder head cover? — Go to Step 2 Go to Step 4

2 Were valve clearances correct? 0.4 mm

(0.016 in)

both intake

and exhaust

Adjust the

valve

clearances Go to Step 3

3 Were the rocker arms damaged? — Replace the

rocker arms Go to Step 4

4 Was the flywheel fixing bolt loose? — Tighten the

fixing bolt. Go to Step 5

5 Was noise coming from the cylinder body? — Go to Step 6 Go to Step 10

6 Inspect the crankshaft bearing and/or crankshaft.

Was the crankshaft bearing and/or crankshaft worn?

— Replace the

worn parts Go to Step 7

7 Inspect the connecting rod bearing and/or crankpin.

Was the connecting rod bearing and/or crankpin worn?

—

Replace the

worn parts Go to Step 8

8 Inspect the connecting rod small end bushing and/or

piston pin. Was the connecting rod small end bushing and/or piston pin worn?

—

Replace the

worn parts Go to Step 9

9 Inspect the piston and/or cylinder liner.

Was the piston and/or cylinder liner worn or damaged?

— Replace the

worn or

damaged parts Go to Step 10

10 Are any DTC stored? — Go to indicated

DTC Solved

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6 – 14 TROUBLESHOOTING

10-5 Excessive turbocharger noise

The vibration noise (the air aspiration noise) occurred when turbocharger rotates, it is normal condition of the turbocharger, no necessary any actions.

Step Action Value(s) Yes No

1 Was the excessive noise coming from the

turbocharger?

—

Go to Step 2 Go to Step 10

2 Inspect the fixing bolts and bands.

Was any problem found?

— Tighten the

loose parts Go to Step 3

3 Was the intake or exhaust system gasket damaged? — Replace the

damaged

gasket. Go to Step 4

4 Inspect rotation parts condition.

Was the turbine wheel rotation rough?

— Replace the

turbocharger. Go to Step 5

5 Inspect the turbine wheel.

Was the turbine wheel rubbing against housing?

— Replace the

turbocharger. Go to Step 6

6 Was the turbine wheel damaged? — Replace the

turbocharger. Go to Step 7

7 Were there carbon deposits in the turbine or

compressor housing?

— Clean or

replace the

turbocharger. Go to Step 8

8 Inspect the oil supply condition.

Was the oil feed pipe clogged?

— Repair or

replace the oil

feed pipe. Go to Step 9

9 Was the turbine shaft bearing worn? — Replace the

turbocharger. Go to Step 10

10 Are any DTC stored? — Go to indicated

DTC Solved

11. Rotating Part Wear of Turbocharger

Step Action Value(s) Yes No

1 Inspect engine oil.

Was it contaminated with foreign materials?

— Replace the

engine oil Go to Step 2

2 Was the recommended engine oil grade/viscosity

being used?

API CD or

ISUZU genuine/ 10W–30

Go to Step 3

Replace the

engine oil

3 Was the oil feed pipe restricted? — Clean or

replace the oil

feed pipe Go to Step 4

4 Was the oil seal of turbocharger defective? — Replace the oil

seal Go to Step 5

5 Was the center housing oil drain passage clogged? — Clean center

housing or

replace the

turbocharger Go to Step 6

6 Was there oil sludge and/or coking on the turbine

shaft?

— Replace the

turbocharger Go to Step 7

7 Are any DTC stored? — Go to indicated

DTC Solved

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TROUBLESHOOTING 6 – 15

12. Oil Leakage from Turbocharger

Step Action Value(s) Yes No

1 Inspect the oil leakage area.

Was the oil feed pipe eye bolt loose or the gasket broken?

— Tighten the eye

bolt or replace

the gasket. Go to Step 2

2 Were the V band fixing faces tight? — Tighten band or

replace the

turbocharger Go to Step 3

3 Was there oil leakage from the flange of the turbine

housing?

— Replace the

turbocharger Go to Step 4

4 Was there oil leakage from the flange of compressor

housing?

— Tighten the bolt

and/or hose

clamp. Go to Step 5

5 Are any DTC stored? — Go to indicated

DTC Solved

13. Insufficient Acceleration and/or Lack of Power due to turbocharger

Step Action Value(s) Yes No

1 Inspect the air or exhaust route.

Was the air and/or exhaust gas piping loose?

— Tighten flange

bolts or hose

clamp. Go to Step 2

2 Inspect the work of waste gate valve control.

Was there rust on the linkage rod or pin of the waste gate valve?

—

Replace the

turbocharger Go to Step 3

3 Was air leakage found from the actuator piping? — Repair or

replace the

actuator pipe or

hose/ Go to Step 4

4 Inspect the inside of the turbocharger.

Was the turbine shaft end nut loose?

— Replace the

turbocharger Go to Step 5

5 Were the turbine blades bent? — Replace the

turbocharger Go to Step 6

6 Was the turbine wheel rubbing against housing? — Replace the

turbocharger Go to Step 7

7 Are any DTC stored? — Go to indicated

DTC Solved

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6 – 16 TROUBLESHOOTING

14. Battery Charging and Noise Problem

Visual/physical check the following items before diagnosis. The drive belt tension. The battery terminals connection condition. The ground connection condition. The generator and the battery fastener condition. The battery fluid level and specific gravity.

14-1 Battery No Charging

Step Action Value(s) Yes No

1 Was “Visual/Physical Check" performed.

—

Go to Step 2

Go to

visual/physical

check

2 Inspect the brush contact condition on the generator.

Was there poor contact between the brush and the slip ring?

— Repair or

replace the

brush and/or

the slip ring. Go to Step 3

3 Inspect the stator coil on the generator.

Was there an open circuit or the scorching on the stator coil?

—

Replace the

stator coil. Go to Step 4

4 Inspect the rotor coil on the generator.

Was there an open circuit or the scorching on the rotor coil?

—

Replace the

rotor coil. Go to Step 5

5 Inspect the rectifier on the generator.

Was the rectifier defective?

— Replace the

rectifier Go to Step 6

6 Inspect the IC regulator.

Was the IC regulator defective?

— Replace the IC

regulator. Go to Step 7

7 Are any DTC stored? — Go to indicated

DTC. Solved

14-2 Battery Overcharging

Step Action Value(s) Yes No

1 Was “Visual/Physical Check" performed.

—

Go to Step 2

Go to

visual/physical

check

2 Inspect the terminal circuit.

Were the B and F terminals shorted?

— Repair the

short circuit. Go to Step 3

3 Check the regulating voltage.

Was the IC regulator voltage excessive?

— Replace the IC

regulator. Go to Step 4

4 Are any DTC stored? — Go to indicated

DTC. Solved

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TROUBLESHOOTING 6 – 17

14-3 Battery Under Charging

Step Action Value(s) Yes No

1 Was “Visual/Physical Check" performed.

—

Go to Step 2

Go to

visual/physical

check

2 Inspect the brush contact condition on the generator.

Was there intermittent contact between the brush and the slip ring?

— Repair or

replace the

brush holder

assembly. Go to Step 3

3 Inspect the rotor coil on the generator.

Was there a short circuit in the rotor coil?

— Repair or

replace the

rotor coil. Go to Step 4

4 Inspect the stator coil on the generator.

Was there an open circuit or the short circuit on the stator coil?

— Repair or

replace the

stator coil. Go to Step 5

5 Inspect the rectifier on the generator.

Was the rectifier defective?

— Replace the

rectifier Go to Step 6

6 Inspect the IC regulator on the generator.

Was the IC regulator defective?

— Replace the IC

regulator. Go to Step 7

7 Was the electrical load excessive? — Replace more

higher capacity

generator. Go to Step 8

8 Are any DTC stored? — Go to indicated

DTC. Solved

14-4 Battery Unstable Charging Current

Step Action Value(s) Yes No

1 Was “Visual/Physical Check" performed.

—

Go to Step 2

Go to

visual/physical

check

2 Inspect the brush contact condition on the generator.

Was there poor contact between the brush and the slip ring?

— Repair or

replace the

brush and/or

the slip ring. Go to Step 3

3 Inspect the rotor coil on the generator.

Was there the short circuit or an open circuit in the rotor coil?

— Repair or

replace the

rotor coil. Go to Step 4

4 Inspect the stator coil on the generator.

Was there an open circuit or the short circuit in the stator coil?

— Repair or

replace the

stator coil. Go to Step 5

5 Inspect the connection between the rectifier and

stator coil on the generator. Was there a loose connection between the rectifier and stator coil ?

—

Repair the

loose

connection. Go to Step 6

6 Inspect the IC regulator on the generator.

Was the IC regulator defective?

— Replace the IC

regulator. Go to Step 7

7 Are any DTC stored? — Go to indicated

DTC. Solved

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6 – 18 TROUBLESHOOTING

14-5 Charging System Noise

Step Action Value(s) Yes No

1 Was “Visual/Physical Check" performed.

—

Go to Step 2

Go to

visual/physical

check

2 Was there intermittent noise or continuous noise and

that could be identified clearly by increasing and decreasing engine speed?

—

Replace the

bearing. Go to Step 3

3 Was there a growling sound and does this sound

stop when the connector was disconnected?

— Replace the

stator coil. Go to Step 4

4 Was intermittent sound heard when the generator

was running?

— Replace the

brush and/or

slip ring. Go to Step 5

5 Was frictional sound heard when generator was

running?

— Clean the slip

ring or replace

the brush. Go to Step 6

6 Are any DTC stored? — Go to indicated

DTC. Solved

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TROUBLESHOOTING 6 – 19

15. Starter Motor Problem

Visual/physical check the following items before diagnosis. The battery terminals connection condition. The ground connection condition. The starter motor or the battery fastener condition. The battery fluid level and specific gravity.

15-1 Starter motor pinion engages to ring gear but engine does not turn over

Step Action Value(s) Yes No

1 Was “Visual/Physical Check" performed.

—

Go to Step 2

Go to

visual/physical

check

2 Check the contact condition between the brush and

the commutator. Was the brush and the commutator contact intermittent?

— Replace the

brush or repair

the

commutator. Go to Step 3

3 Were the brush and the commutator contact faces

dirty?

—

Clean contact

face Go to Step 4

4 Was the pinion clutch slipped? — Replace the

pinion clutch Go to Step 5

5 Inspect the armature field coil.

Was there an open circuit or a short circuit in the armature field coil?

— Repair or

replace the

armature field

coil. Go to Step 6

6 Are any DTC stored? — Go to indicated

DTC. Solved

15-2 Incorrect pinion and ring gear engagement

Step Action Value(s) Yes No

1 Was “Visual/Physical Check" performed.

—

Go to Step 2

Go to

visual/physical

check

2 Inspect the pinion and the ring gear teeth.

Were the pinion and/or the ring gear teeth worn or broken?

—

Replace the

wron parts. Go to Step 3

3 Inspect the pinion gear return movement.

Was the pinion gear return movement incorrect?

— Adjust or

replace the

movement

parts. Go to Step 4

4 Are any DTC stored? — Go to indicated

DTC. Solved

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6 – 20 TROUBLESHOOTING

15-3 Starter motor continues to run after the starter switch is turned off

Step Action Value(s) Yes No

1 Was “Visual/Physical Check" performed.

—

Go to Step 2

Go to

visual/physical

check

2 Inspect the magnetic switch contact point.

Was the contact point seized?

— Repair or

replace the

magnetic

switch. Go to Step 3

3 Inspect the starter switch.

Was the starter switch defective?

— Replace the

starter switch. Go to Step 4

4 Are any DTC stored? — Go to indicated

DTC. Solved

15-4 Excessive commutator sparking

Step Action Value(s) Yes No

1 Was “Visual/Physical Check" performed.

—

Go to Step 2

Go to

visual/physical

check

2 Inspect the contact condition between the brush and

the commutator. Was the brush and the commutator contact intermittent?

— Replace the

brush or repair

the

commutator. Go to Step 3

3 Was there the slag accumulation on the contact

face?

— Clean the

contact face or

replace the

brush. Go to Step 4

4 Was the brush holder loose? — Repair the

brush holder Go to Step 5

5 Inspect the commutator.

Was there excessive wear or pitting?

— Repair or

replace the

commutator. Go to Step 6

6 Was there loose the solder on the commutator? — Clean and

repair Go to Step 7

7 Inspect the armature shaft.

Was the run-out of armature shaft outside the standard value due to worn bearing ?

—

Replace the

bearing Go to Step 8

8 Are any DTC stored? — Go to indicated

DTC. Solved

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ENGINE MECHANICAL 6A – 1

SECTION 6A

ENGINE MECHANICAL

TABLE OF CONTENTS

PAGE

Main Data and Specifications....................................................................................... 6A - 4

Torque Specification..................................................................................................... 6A - 8

Standard Bolts........................................................................................................... 6A - 8

Special Parts Fixing Nuts and Bolts........................................................................ 6A - 9

Recommended Liquid Gasket ...................................................................................... 6A - 22

LOCTITE Application Procedure.................................................................................. 6A - 23

Servicing ........................................................................................................................ 6A - 24

Model Identification ................................................................................................... 6A - 24

Air Cleaner.................................................................................................................. 6A - 24

Lubricating System.................................................................................................... 6A - 24

Fuel System................................................................................................................ 6A - 25

Cooling System.......................................................................................................... 6A - 27

Valve Clearance Adjustment..................................................................................... 6A - 31

Compression Pressure Measurement ..................................................................... 6A - 32

General Description ...................................................................................................... 6A- 36

Removal and Installation .............................................................................................. 6A- 37

Removal...................................................................................................................... 6A- 37

Installation.................................................................................................................. 6A- 40

Coolant Replenishment ......................................................................................... 6A- 41

Engine Warm-Up .................................................................................................... 6A- 41

Engine Repair Kit........................................................................................................... 6A- 42

Engine Overhaul............................................................................................................ 6A- 43

Removal...................................................................................................................... 6A- 43

External Parts ......................................................................................................... 6A- 43

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6A – 2 ENGINE MECHANICAL

Disassembly............................................................................................................... 6A- 47

Internal Parts .......................................................................................................... 6A- 47

Major Components ............................................................................................. 6A- 47

Minor Components ............................................................................................. 6A- 56

Rocker Arm Shaft and Rocker Arm ............................................................... 6A- 56

Cylinder Head.................................................................................................. 6A- 57

Piston and Connecting Rod ........................................................................... 6A- 59

Inspection and Repair ............................................................................................... 6A- 61

Cylinder Head ......................................................................................................... 6A- 61

Rocker Arm Shaft and Rocker Arm....................................................................... 6A- 68

Cylinder Body......................................................................................................... 6A- 69

Camshaft................................................................................................................. 6A- 77

Crankshaft and Bearing......................................................................................... 6A- 79

Crankshaft Bearing Selection ............................................................................... 6A- 83

Crankshaft Pilot Bearing ....................................................................................... 6A- 85

Flywheel and Ring Gear......................................................................................... 6A- 85

Piston ...................................................................................................................... 6A- 86

Cylinder Head Gasket Selection ........................................................................... 6A- 88

Connecting Rod...................................................................................................... 6A- 90

Idler Gear Shaft and Idler Gear ............................................................................. 6A- 91

Timing Gear Case Cover........................................................................................ 6A- 91

Reassembly................................................................................................................ 6A- 93

Internal Parts .......................................................................................................... 6A- 93

Minor Component ............................................................................................... 6A- 93

Rocker Arm Shaft and Rocker Arm ............................................................... 6A- 93

Cylinder Head.................................................................................................. 6A- 94

Piston and Connecting Rod ........................................................................... 6A- 96

Positive Crankcase Ventilation (PCV) Valve................................................. 6A- 99

Major Component ............................................................................................... 6A- 101

Installation.................................................................................................................. 6A- 118

External Parts ......................................................................................................... 6A- 118

Lubrication System ....................................................................................................... 6A- 126

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ENGINE MECHANICAL 6A – 3

Lubricating Flow ........................................................................................................ 6A- 126

Oil Pump and Oil Filter .............................................................................................. 6A- 127

Oil Pump ..................................................................................................................... 6A- 128

Disassembly ........................................................................................................... 6A- 128

Inspection and Repair............................................................................................ 6A- 129

Reassembly ............................................................................................................ 6A- 130

Oil Filter and Oil Cooler............................................................................................. 6A- 131

Disassembly ........................................................................................................... 6A- 131

Inspection and Repair............................................................................................ 6A- 132

Reassembly ............................................................................................................ 6A- 133

Inter Cooler ................................................................................................................... 6A- 135

Removal ................................................................................................................. 6A- 136

Installation ............................................................................................................. 6A- 136

Special Tools ................................................................................................................. 6A- 137

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6A – 4 ENGINE MECHANICAL

MAIN DATA AND SPECIFICATIONS

Engine model

Item

4JA1T (L) 4JA1TC

Engine type

Combustion chamber type

Cylinder liner type

Timing gear train system

Four-cycle, overhead valve, water cooled

Direct injection

Dry type, chrome plated

Gear drive

No. of cylinders-bore × stroke mm (in) 4 – 93 × 92 (3.66 × 3.62)

No. of piston rings Compression ring: 2 / Oil ring: 1

Total piston displacement cm3 (in3)

Compression ratio (to 1)

2,499 (152.4)

18.5

Compression pressure MPa (kg/cm2/psi) 3.0 (31.0/441) – 200 rpm

SEngine weight (dry) kg (lb) Approximately 239 (527)

Fuel injection order 1 – 3 – 4 - 2

Fuel injection timing BTDC deg 8 -

JIS No. 2, DIN/EN590, GB252-1944 Diesel fue

730 ± 25 (A/C OFF)

850 ± 25 (A/C ON)

730 ± 25 (A/C OFF)

780 ± 25 (A/C ON)

Specified fuel type

Idling speed rpm

Valve clearances (At cold): Intake mm (in)

Exhaust mm (in)

Intake valves Open at (BTDC) deg

Close at (ABDC) deg

Exhaust valves Open at (BBDC) deg

Close at (ATDC) deg

Fuel system

0.4 (0.016)

24.5

55.5

54.0

26.0

Injection pump type BOSCH distributor VE type BOSCH distributor VP44 type

Governor type Mechanical (Half all speed

type)

Electronically controled

Injection nozzle type

Injection nozzle opening pressure

Hole with 5 orifices

MPa (kg/cm2/psi) 1st 19.1 (195 / 2,773) 1st 19.0 (194 / 2,755)

2nd (Reference)

25.5∼27.0

(260∼275 / 3,702∼3,920)

2nd (Reference)

34.0∼35.5

(347∼362 / 4,936∼5,154)

Main fuel filter type

Lubricating system

Lubricating method

Cartridge paper element and water separator

Pressure circulation

Specified engine oil (API grade) ISUZU genuine 10W – 30 (API CD of ACEA B2/B3)

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ENGINE MECHANICAL 6A – 5

Engine model

Item

4JA1T (L) 4JA1TC

Cooling system

Water pump type Centrifugal

Thermostat type Wax pellet with jiggle valve

Air cleaner type Dry paper element Viscous paper element

Battery type/voltage × No. of units 80D26L × 1

95D31L × 1 (OPT)

Generator capacity V-A 12 – 60

12 – 80

Starter motor output V-kW 12 – 2.3

Turbocharger model

Turbine type

Compressor type

*IHI RHF 4H

Mixed flow type

Backward & rake

*IHI: Ishikawajima-Harima Heavy Industries., Ltd.

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6A – 6 ENGINE MECHANICAL

MAIN DATA AND SPECIFICATIONS

Engine model

Item

4JH1TC

Engine type Four-cycle, overhead valve, water cooled

Combustion chamber type Direct injection

Cylinder liner type

Timing gear train system

Dry type, chrome plated

Gear drive

No. of cylinders-bore × stroke mm (in) 4 – 95.4 × 104.9 (3.76 × 4.13)

No. of piston rings Compression ring: 2 / Oil ring: 1

Total piston displacement cm3 (in3)

Compression ratio (to 1)

2,999 (183.0)

18.3

Compression pressure MPa (kg/cm2/psi) 3.0 (31.0/441) – 200 rpm

Engine weight (dry) kg (lb) MT: Approximately 249 (549)

AT: Approximately 236 (520)

Fuel injection order 1 – 3 – 4 - 2

Specified fuel type JIS No.2, DIN/EN590, GB252-1944 Diesel fuel

Idling speed rpm

700 ± 25 (A/C OFF)

800 ± 25 (A/C ON)

Valve clearances (At cold): Intake mm (in)

Exhaust mm (in)

Intake valves Open at (BTDC) deg

Close at (ABDC) deg

Exhaust valves Open at (BBDC) deg

Close at (ATDC) deg

Fuel system

Injection pump type

0.4 (0.016)

24.5

55.5

54.0

26.0

BOSCH distributor VP44 type

Injection nozzle type

Injection nozzle opening pressure

MPa (kg/cm

/psi)

Hole with 5 orifices

1st 19.5 (199/2,828)

2nd (Reference) 34.3∼35.8 (350∼365/4,980∼5,197)

Main fuel filter type

Lubricating system

Lubricating method

Cartridge paper element and water separator

Pressure circulation

Specified engine oil (API grade) ISUZU genuine 10W – 30 (API CD of ACEA B2/B3)

Oil pump type

Oil filter type

Gear

Cartridge paper element

Oil capacity lit (US/UK gal)

6.2 (1.64/1.36) (For 4 × 2)

7.0 (1.85/1.54) (For 4 × 4)

Oil cooler type Water cooled

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ENGINE MECHANICAL 6A – 7

Engine model

Item

4JH1TC

Cooling system

Water pump type

Thermostat type

Air cleaner type

Battery type/voltage × No. of units

Generator capacity V-A

Starter motor output V-kW

Turbocharger model

Turbine type

Compressor type

Centrifugal

Wax pellet with jiggle valve

Dry paper element (except for Euro3 spec)

Viscous paper element (for Euro3 spec)

80D26L × 1

95D31L × 1 (OPT)

75D26R × 2 (OPT for EC, MT)

80D26R × 2 (OPT for EC, AT)

12 – 60/12 – 80

12 – 2.3

*IHI RHF5

Mixed flow type Radial-inflow

Backward & rake type Radial-outflow

*IHI: Ishikawajima-Harima Heavy Industries., Ltd.

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6A – 8 ENGINE MECHANICAL

TORQUE SPECIFICATION

STANDARD BOLTS

The torque values given in the following table should be applied whenever a particular torque is not specified.

N·m (kg·m/lb·ft)

8.8

4.8 (4T) (7T)

Refined

Non-Refined

9.8 (9T)

Strength

Class

Bolt Identification

Bolt Diameter × Pitch (mm)

M 6 ×××× 1.0

M 8 ×××× 1.25

M 10 ×××× 1.25

M 12 ×××× 1.25

M 14 ×××× 1.5

M 16 ×××× 1.5

M 18 ×××× 1.5

M 20 ×××× 1.5

M 22 ×××× 1.5

M 24 ×××× 2.0

* M 10 ×××× 1.5

* M 12 ×××× 1.5

* M 14 ×××× 2.0

* M 16 ×××× 2.0

5.88 ± 1.96

(0.60 ± 0.20/4.33 ± 1.44)

12.74 ± 4.90

(1.30 ± 0.50/9.40 ± 3.62)

27.44 ± 6.86

(2.80 ± 0.70/20.25 ± 5.06)

61.25 ± 12.25

(6.25 ± 1.25/45.21 ± 9.04)

95.55 ± 19.11

(9.75 ±1.95/70.52 ± 14.10)

130.34 ± 26.46

(13.30 ± 2.70/96.20 ± 19.53)

188.16 ± 37.24

(19.20 ± 3.80/138.87 ± 27.49)

257.74 ± 51.94

(26.30 ± 5.30/190.23 ± 38.33)

332.22 ± 81.34

(33.90 ± 8.30/245.20 ± 60.03)

448.84 ± 90.16

(45.80 ± 9.20/331.27 ± 66.54)

26.46 ± 6.86

(2.70 ± 0.70/19.53 ± 5.06)

56.84 ± 11.76

(5.80 ± 1.20/41.95 ± 8.68)

89.18 ± 17.64

(9.10 ± 1.80/65.82 ± 13.02)

124.46 ± 24.50

(12.70 ± 2.50/91.86 ± 18.08)

7.35 ± 2.45

(0.75 ± 0.25/5.43 ± 1.80)

17.15 ± 5.39

(1.75 ± 0.55/12.66 ± 4.00)

36.75 ± 9.31

(3.75 ± 0.95/27.12 ± 6.87)

75.95 ± 15.19

(7.75 ± 1.55/56.06 ± 11.21)

116.13 ± 23.03

(11.85 ± 2.35/85.71 ± 17.00)

169.54 ± 34.30

(17.30 ± 3.50/125.13 ± 25.32)

244.02 ± 49.00

(24.90 ± 5.00/180.10 ± 36.17)

337.12 ± 67.62

(34.40 ± 6.90/248.82 ± 49.41)

453.25 ± 90.65

(46.25 ± 9.25/334.53 ± 66.91)

570.36 ± 140.14

(58.20 ± 14.30/420.96 ± 103.43)

36.26 ± 8.82

(3.70 ± 0.90/26.76 ± 6.50)

70.56 ± 13.72

(7.20 ± 1.40/52.08 ± 10.13)

109.76 ± 21.56

(11.20 ± 2.20/81.01 ± 15.91)

161.70 ± 32.34

(16.50 ± 3.30/119.34 ± 23.87)

23.52 ± 6.86

(2.40 ± 0.70/17.36 ± 5.06)

49.98 ± 12.74

(5.10 ± 1.30/36.89 ± 9.40)

94.57 ± 19.11

(9.65 ± 1.95/69.80 ± 14.10)

142.10 ± 28.42

(14.50 ± 2.90/104.88 ± 21.00)

199.92 ± 40.18

(20.40 ± 4.10/147.55 ± 29.66)

287.14 ± 57.82

(29.30 ± 5.90/211.93 ± 42.67)

395.92 ± 79.38

(40.40 ± 8.10/292.21 ± 58.59)

530.18 ± 105.84

(54.10 ± 10.80/391.30 ± 78.12)

691.88 ± 138.18

(70.60 ± 14.10/510.65 ± 101.99)

48.02 ± 11.76

(4.90 ± 1.20/35.44 ±8.68)

89.18 ± 17.64

(9.10 ± 1.80/65.82 ± 13.02)

133.28 ± 26.46

(13.60 ± 2.70/98.37 ± 19.53)

191.10 ± 38.22

(19.50 ± 3.90/141.04 ± 28.21)

An asterisk (*) indicates that the bolts are used for female threaded parts that are made of soft materials such as casting. Those shown in parentheses in the strength class indicate the classification by the old standard.

FLARE NUTS

N·m (kg·m/lb·ft)

Pipe diameter mm

(in)

Torque

Pipe diameter mm

(in)

Torque

4.76 (0.187)

6.35 (0.250)

8.00 (0.315)

15.2 ± 2.45(1.55 ±0.25/11.2 ± 1.8)

26.48 ± 2.94(2.70 ± 0.30/19.5 ± 2.1)

44.14 ± 4.90(4.50 ± 0.50/32.5 ± 3.6)

10.00 (0.394)

12.00 (0.472)

15.00 (0.591)

53.95 ± 4.90(5.50 ± 0.5 /39.7 ± 3.6)

88.29 ± 9.80(9.00 ± 1.0/65.0 ± 7.2)

105.45 ± 12.26(10.75 ± 1.25/77.7 ± 9.0)

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