Isuzu 4JA1, 4JH1 Workshop Manual

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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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ENGINE MECHANICAL 6A – 9

SPECIAL PARTS FIXING NUTS AND BOLTS

Cylinder Head Cover, Cylinder Head, and Rocker Arm Shaft Bracket

N·m (kg·m/lb·ft)

RTW86AXF000101

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6A – 10 ENGINE MECHANICAL

Crankshaft Bearing Cap, Connecting Rod Bearing Cap, Crankshaft Damper Pulley, Flywheel, and Oil Pan

N·m (kg·m/lb·ft)

RTW86AXF000101

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ENGINE MECHANICAL 6A – 11

Timing Gear Case, Pulley Housing, Timing Gear, and Camshaft

N·m (kg·m/lb·ft)

RTW46AXF000601

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6A – 12 ENGINE MECHANICAL

Cooling and Lubricating System

N·m (kg·m/lb·ft)

RTW46AXF000701

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ENGINE MECHANICAL 6A – 13

Intake Manifold (4JA1TC / 4JH1TC)

N·m (kg·m/lb·ft)

RTW36AXF000201

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6A – 14 ENGINE MECHANICAL

EGR Valve, EGR Pipe, EGR Cooler

RTW46AXF000801

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ENGINE MECHANICAL 6A – 15

Exhaust Manifold, and Turbocharger (4JA1L)

RTW46AXF000901

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6A – 16 ENGINE MECHANICAL

Exhaust Manifold, and Turbocharger (4JA1TC/4JH1TC)

N·m (kg·m/lb·ft)

RTW86AXF000301

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ENGINE MECHANICAL 6A – 17

Engine Electricals

N·m (kg·m/lb·ft)

RTW36AXF000501

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6A – 18 ENGINE MECHANICAL

Fuel Injection System (4JA1L)

N·m (kg·m/lb·ft)

RTW86AXF000201

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ENGINE MECHANICAL 6A – 19

Fuel Injection System (4JA1TC)

N·m (kg·m/lb·ft)

RTW46AXF001201

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6A – 20 ENGINE MECHANICAL

Fuel Injection System (4JH1TC)

N·m (kg·m/lb·ft)

RTW46AXF001301

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ENGINE MECHANICAL 6A – 21

Engine Mounting Bracket

N·m (kg·m/lb·ft)

022R300001

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6A – 22 ENGINE MECHANICAL

RECOMMENDED LIQUID GASKET

Type Brand Name Manufacturer Remarks

RTV*

Silicon Base

ThreeBond 1207B ThreeBond 1207C

Three Bond Three Bond

Water Base ThreeBond 1141E

ThreeBond 1215

Three Bond Three Bond

Solvent ThreeBond 1104

Belco Bond 4 Belco Bond 401 Belco Bond 402

Three Bond Isuzu Isuzu Isuzu

Anaerobic LOCTITE 515

LOCTITE 518 LOCTITE 262

Loctite Loctite Loctite

Recommended for transaxle repairs

* RTV : Room Temperature Vulcanizer

Note:

1. It is very important that the liquid gaskets listed above or their exact equivalent be used on the vehicle.

2. Be careful to use the specified amount of liquid gasket. Follow the manufacturer’s instructions at all times.

3. Be absolutely sure to remove all lubricants and moisture from the connecting surfaces before applying the liquid gasket. The connecting surfaces must be perfectly dry.

4. LOCTITE 515 and LOCTITE 518 harden upon contact with a metal surface. Do not apply LOCTITE 515 or LOCTITE 518 between two metal surfaces having a clearance of greater than 0.25 mm (0.01 in). Poor adhesion will result.

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ENGINE MECHANICAL 6A – 23

LOCTITE APPLICATION PROCEDURE

LOCTITE Type LOCTITE Color Application Steps

LOCTITE 242 Blue

LOCTITE 262 Red

LOCTITE 270 Green

LOCTITE 271 Red

1. Completely remove all lubricant and moisture from the bolts and the female threaded surfaces of the parts to be joined. The surfaces must be perfectly dry.

2. Apply LOCTITE to the bolts.

3. Tighten the bolts to the specified torque.

4. Wait at least one hour before continuing the installation procedure.

LOCTITE 515 Violet

1. Completely remove lubricant and moisture from the connecting surfaces. The surfaces must be perfectly dry.

2. Apply a 2.0 – 2.5 mm bead of LOCTITE to one of the connecting surfaces. There must be no gaps in the bead.

3. Tighten the bolts to the specified torque.

4. Let the joined parts set for at least thirty minutes.

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6A – 24 ENGINE MECHANICAL

SERVICING

Servicing refers to general maintenance procedures to be performed by qualified service personnel.

RTW36ASH000401

MODEL IDENTIFICATION

Engine Serial Number

The engine number is stamped on the rear left hand side of the cylinder body.

The engine number is stamped in the plate in front of the engine room as well.

AIR CLEANER

Element cleaning procedures will vary according to the condition of the element.

Dust Fouled Element (Except wet type element)

Rotate the element with your hand while applying compressed air to the inside of the element. This will blow the dust free.

Compressed air pressure kPa (kg/cm

/psi)

392 – 490 (4 – 5/57 – 71)

LUBRICATING SYSTEM

Main Oil Filter (Cartridge Type Paper Element) Replacement Procedure

1. Drain the engine oil.

2. Retighten the drain plug.

3. Loosen the used oil filter by turning it counterclockwise with a filter wrench. Filter Wrench: 5-8840-0203-1

RTW36ASH000101

4. Clean the oil cooler fitting face. This will allow the new oil filter to seat properly.

5. Apply a light coat of engine oil to the filter O-ring.

6. Turn in the new oil filter until the filter O-ring is fitted against the sealing face.

7. Use the filter wrench to turn in the filter an additional 2/3 turns. Filter Wrench: 5-8840-0203-1

8. Check the engine oil level and replenish to the specified level if required.

130RY00003

6A-6

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ENGINE MECHANICAL 6A – 25

Replenished Engine Oil MAX lit (US/UK gal)

Condition

Model

Engine Dry With oil filter

replacement

Without oil

filter

replacement

4 × 2 4 × 4

(4JA1L/TC)

6.2 (1.64/1.36) 5.2 ∼ 4.2 (1.37 ∼ 1.11

/ 1.14 ∼ 0.92)

4.5 ∼ 3.5

(1.19 ∼ 0.93

/ 0.99 ∼ 0.77)

4 × 2

(4JH1TC)

6.2 (1.64/1.36) 5.2 ∼ 4.2 (1.37 ∼ 1.11

/ 1.14 ∼ 0.92)

4.5 ∼ 3.5

(1.19 ∼ 0.93

/ 0.99 ∼ 0.77)

4 × 4

(4JH1TC)

7.0 (1.85/1.54) 6.2 ∼ 5.2 (1.64 ∼ 1.37

/ 1.36 ∼ 1.14)

5.3 ∼ 4.3

(1.72 ∼ 1.14

/ 1.17 ∼ 0.95)

9. Start the engine and check for oil leakage from the main oil filter.

RTW66ASH003201

FUEL SYSTEM

Fuel Filter Replacement Procedure

1. Remove the fuel filter by turning it counterclockwise

with a filter wrench. Filter Wrench: 5-8840-0253-0

Note: Be careful not to spill the fuel in the filter cartridge.

RTW66ASH003301

2. Clean the fuel filter cartridge fitting faces.

This will allow the new fuel filter to seat properly

3. Apply a light coat of engine oil to the O-ring.

4. Turn in the fuel filter until the sealing face comes in

contact with the O-ring.

5. Turn in the fuel filter an additional 2/3 of a turn with a

filter wrench. Filter Wrench : 5-8840-0253-0

6. Operate the priming pump until the air discharged

completely from fuel system.

7. Start the engine and check for fuel leakage.

Note: The use of an ISUZU genuine fuel filter is strongly

recommended.

041RY00009

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6A – 26 ENGINE MECHANICAL

041RY00011

Draining Procedure

The indicator light will come on when the water level in the water separator exceeds the specified level.

Drain the water and foreign material from the water separator (inside chassis frame) with the following procedure.

1. Place the drain pan under the drain plug.

2. Loosen the drain plug and drain water.

3. After draining the water, tighten the drain plug.

4. Operate the priming pump on the fuel filter several

times and check for fuel leakage.

5. Check the water separator indicator light. It should be

off.

Except EURO III model

RTW46ASH002901

For EURO III model

RTW46ASH000501

Air Bleeding

1. Operate the priming pump until strong resistance is

felt.

2. Wait 1 minute, and operate the priming pump until

strong resistance is felt.

3. Once more wait, and operate the priming pump until

strong resistance is felt.

4. Turn the ignition switch to the "ON" position. Wait until

the glow indicator lamp turns off.

5. Turn the ignition switch to the "START" position and

crank the engine until it starts.

6. If the engine does not start, repeat Step 3 - 5.

7. Allow the engine to idle for 3 minutes to bleed air

completely form the fuel system and check for fuel leakage.

Note: Insufficient air bleeding may cause the Diagnostic

Trouble Code (DTC) store or improper engine performance.

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ENGINE MECHANICAL 6A – 27

111R300001

COOLING SYSTEM

Coolant Level

Check the coolant level and replenish the radiator reserve tank as necessary.

If the coolant level falls below the “MIN” line, carefully check the cooling system for leakage. Then add enough coolant to bring the level up to the “MAX” line.

Engine coolant Filling up procedure

1. Make sure that the engine is cool.

Warning: When the coolant is heated to a high temperature, be

sure not to loosen or remove the rediator cap. Otherwise you might get scalded by hot vapor or boiling water. To open the radiator cap, put a piece of thick cloth on the cap and loosen the cap slowly to reduce the pressure when the coolant has become cooler.

2. Open rediator cap pour coolant up to filler neck

3. Pour coolant into reservoir tank up to “MAX” line

4. Tighten radiator cap and start the engine. After idling

for 2 to 3 minutes, stop the engine and reopen radiator cap. If the water level is lower, replenish.

5. After replenish the coolant tighten radiator cap, warm

up the engine at about 2000 rpm. Set heater adjustment to the highest temperature position, and let the coolant circulate also into heater water system.

6. Check to see the thermometer, continuously idling 5

minutes and stop the engine.

7. When the engine has been cooled, check filler neck

for water level and replenish if required. Should extreme shortage of coolant is found, check the coolant system and reservoir tank hose for leakage.

8. Pour coolant into the reservoir tank up to “MAX” line.

Engine Coolant Total Capacity Lit (U.S / UK gal)

4JA1 / TC 9.4 (2.5 / 2.1)

4JH1TC

M/T: 10.1 (2.7 / 2.2)

A/T: 10.0 (2.6 / 2.2)

Mixing Ratio (Anti-Freeze Solution/Water)

50 %

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6A – 28 ENGINE MECHANICAL

Cooling System Inspection

Install a radiator filler cap tester to the radiator. Apply testing pressure to the cooling system to check for leakage. The testing pressure must not exceed the specified pressure.

Testing Pressure kPa(kg/cm

/psi)

150 (1.5/21)

Radiator Cap Inspection

The radiator filler cap is designed to maintain coolant pressure in the cooling system at 103 kPa(1.05 kg/cm

15psi). Check the radiator filler cap with a radiator filler cap tester.

The radiator filler cap must be replaced if it fails to hold the specified pressure during the test procedure.

Radiator Cap Valve Opening Pressure kPa(kg/cm

/psi)

90 – 120 (0.9 – 1.2/13 – 17)

Negative Valve (Reference) kPa(kg/cm2 /psi)

1.9 – 4.9 (0.02 – 0.05/0.28 – 0.71)

030LX003

030LX002

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ENGINE MECHANICAL 6A – 29

Thermostat Operating Test

1. Completely submerge the thermostat in water.

2. Heat the water.

Stir the water constantly to avoid direct heat being applied to the thermostat.

3. Check the thermostat initial opening temperature.

Thermostat Initial Opening Temperature °C (°F)

82 (180)

Oil Cooler Thermo Valve °C (°F)

76.5 (170)

EGR Cooler Thermo Valve °C (°F)

40 (104)

4. Check the thermostat full opening temperature.

Thermostat Full Opening Temperature °C (°F)

95 (203)

Oil Cooler Thermo Valve °C (°F)

90 (194)

EGR Cooler Thermo Valve °C (°F)

55 (131)

Valve Lift at Fully Open position mm (in)

9.5 (0.37)

Oil Cooler Thermo Valve mm (in)

4.5 (0.18)

EGR Cooler Thermo Valve mm in)

3.5 (0.14)

Drive Belt Adjustment

Check drive belts for wear or damage, and replace with new ones as necessary. Check belts for tension, and adjust as necessary.

1 Crankshaft damper pulley 2 Generator pulley 3 Cooling fan pulley 4 Oil pump pulley or idler pulley 5 Compressor pulley or idler pulley

030LX014

033RY00002

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6A – 30 ENGINE MECHANICAL

Cooling Fan Pulley Drive Belt

Fan belt tension is adjusted by moving the generator. Depress the drive belt mid-portion with a 98N (10 kg/22 lb)

force. Cooling Fan Drive Belt Deflection mm (in)

New belt 4 - 7 (0.16 - 0.28) Reuse belt 6 - 9 (0.24 - 0.35)

1 Crankshaft damper pulley 2 Generator pulley 3 Cooling fan pulley

A/C Compressor Drive Belt

Compressor belt tension is adjusted by moving the P/S pumppulley.

Depress the drive belt mid-portion with a 98N (10 kg/22 Ib) force. A/C Compressor Drive Belt Deflection mm (in)

New belt 9 - 10 (0.35 - 0.39) Reuse belt 12 - 13 (0.47 - 0.51)

1 Crankshaft damper pulley 2 P/S pump pulley 2 A/C Compressor pulley

033RY00003

033RY00004

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ENGINE MECHANICAL 6A – 31

VALVE CLEARANCE ADJUSTMENT

1. Bring the piston in either the No. 1 cylinder or the No. 4 cylinder to TDC on the compression stroke by turning the crankshaft until the crankshaft damper pulley TDC line is aligned with the timing pointer.

014RY00014

2. Check the rocker arm shaft bracket nuts for

looseness. Tighten any loose rocker arm shaft bracket nuts

before adjusting the valve clearance.

Rocker Arm Shaft Bracket Nut Torque N·m (kg·m /lb·ft)

54 (5.5/40)

014RY00015

8. Check for play in the No. 1 intake and exhaust valve

push rods. If the No. 1 cylinder intake and exhaust valve push

rods have play, the No. 1 piston is at TDC on the compression stroke.

If the No. 1 cylinder intake and exhaust valve push rods are depressed, the No. 4 piston is at TDC on the compression stroke.

014RY00016

Adjust the No.1 or the No. 4 cylinder valve clearances while their respective cylinders are at TDC on the compression stroke.

Valve Clearance (At Cold) mm (in)

0.4 (0.016)

9. Loosen each valve clearance adjusting screw as

shown in the illustration.

10. Insert a feeler gauge of the appropriate thickness

between the rocker arm and the valve stem end.

014RY00017

11. Turn the valve clearance adjusting screw until a slight

drag can be felt on the feeler gauge.

12. Tighten the lock nut securely.

13. Rotate the crankshaft 360°.

14. Realign the crankshaft damper pulley TDC notched

line with the timing pointer.

15. Adjust the clearances for the remaining valves as

shown in the illustration.

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6A – 32 ENGINE MECHANICAL

COMPRESSION PRESSURE MEASUREMENT

1. Start the engine and allow it to idle until the coolant

temperature reaches 70 – 80 °C (158 – 176 °F).

2. Remove the following parts.

• Leak off pipe

• Injection nozzle holder bracket

• Injection nozzle holder

3. Install the following parts.

• Set the adapter and compression gauge (SST) to

the No.1 cylinder injection nozzle hole.

• Injection nozzle holder bracket

Injection nozzle holder bracket Bolt Torque N·m (kg·m /lb·ft)

37 (3.8/27)

Compression Gauge: 5-8840-2675-0 Adapter; Compression Gauge: 5-8531-7001-0

4. Turn the engine over with the starter motor and take

the compression gauge reading.

Compression Pressure MPa (kg/cm

/psi) at 200 rpm

Standard Limit

3.0 (31.0/441) 2.1 (21.7/309)

5. Repeat the procedure (Steps 3 and 4) for the

remaining cylinders. If the measured value is less than the specified limit,

refer to “Troubleshooting” in this Manual.

F06XL056

901R100003

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ENGINE MECHANICAL 6A – 33

INJECTION TIMING ADJUSTMENT (4JA1T(L) only)

1. Check that the notched line on the injection pump flange is aligned with the front plate or the timing gear case notched line.

2. Bring the piston in the No. 1 cylinder to TDC on the

compression stroke by turning the crankshaft until the crankshaft pulley TDC line is aligned with the timing mark.

Note: Check for play in the No. 1 intake and exhaust valve

push rods. If the No. 1 cylinder intake and exhaust valve push rods have play, the No. 1 piston is at TDC on the compression stroke.

RTW46ASH000601

3. Disconnect the injection pipe from the injection pump

4. Remove one bolt from the distributor head.

5. Install the adapter set, togather with static timing

gauge. The probe of the gauge should be depressed inward

approximately 2 mm (0.079 in). Static Timing Gauge: 5-8840-0145-0 (J-28827) Adapter Set: Static Timing Gauge: 5-8840-2834-0

RTW36ASH002101

6. Rotate the crankshaft to bring the piston in the No. 1

cylinder to a point 30 - 40° BTDC.

7. Set the timing gauge needle to zero.

8. Move the crankshaft pulley slightly in both directions to

check that the gauge indication is stable.

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6A – 34 ENGINE MECHANICAL

RTW46ASH000701

9. Turn the crankshaft clockwise and read the gauge

indication when the crankshaft pulley timing mark (8°) is aligned with the pointer.

Injection Timing : BTDC 8° ± 2°

Standard Reading mm (in)

0.5 (0.02)

If the injection timing is outside the specified range,

continue with the following steps.

10. Loosen the injection pump fixing nuts and bracket bolts.

11. Adjust the injection pump setting angle.

When large than standard

value

When smaller than standard

value

R A

A: Move the injection pump toward the engine. R: Move the injection pump away from the engine.

12. Install the distributor head bolt.

Distributor head bolt torque N·m (kg·m /lb·ft)

29 (3.0/22)

ENGINE CONTROL (4JA1T(L) only)

Idling Speed Adjustment

1. Set the vehicle parking brake and chock the drive

wheels.

2. Place the transmission in neutral.

3. Start the engine and allow it to idle until the coolant

temperature reaches 70 - 80°C (158 - 176°F).

4. Disconnect the engine control cable from the control

lever.

5. Set a tachometer to the engine.

6. Check the engine idling speed.

If the engine idling speed is outside the specified range, it must be adjusted.

Engine Idling Speed : 730 ± 25 rpm

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ENGINE MECHANICAL 6A – 35

Idling Speed Adjustment

1. Loosen the idling set screw lock nut c on the injection

pump idling set bolt.

2. Adjust the idling speed to the specified range by

turning the idling set bolt

3. Lock the engine set nut

with the idling set bolt lock

nut.

4. Check that the idling control cable is tight (free of

slack). If required, remove the slack from the cable.

Fast Idling Speed Inspection

1. Set tachometer to the engine.

2. Disconnect the vacuum hose

from the fast idle

actuator

on the injection pump.

3. Disconnect the other vacuum hose

from the

vacuum switching valve

and connect it to the fast

idle actuator

The vacuum line will now be connected directly from the vacuum pump

to the fast idle actuator.

4. Check the engine fast idling speed.

If the engine idling speed is outside the specified range, it must be adjusted.

Fast Idling Speed rpm

850 ± 25

Fast Idling Speed Adjustment

1. Loosen the fast idle actuator bracket bolts.

2. Adjust the fast idling speed by moving the actuator bracket, so that the clearance “S” can be 1 ~ 2 mm (0.04 ~ 0.08 in.).

3. Tighten the bracket bolts.

Accelerator Control Cable Adjustment

Refer to Sec. 6H-6 (Accelerator Control)

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6A – 36 ENGINE MECHANICAL

GENERAL DESCRIPTION

RTW46AMF000401

The 4J series automotive diesel engine has special designed combustion chambers in the piston. This design provides superior fuel economy over a wide range of driving conditions. Auto-thermatic pistons with cast steel struts are used to reduce thermal expansion and resulting engine noise when the engine is cold. Chrome plated dry type cylinder liners provide the highest durability. The laminated steel sheet cylinder head gasket is very durable and, to increase the head gasket reliability. The crankshaft has been tufftrided to provide a longer service life. Because the crankshaft is tufftrided, it cannot be reground. The 4JA1T(L) engine is equipped with the BOSCH VE-Type distributor injection pump. The 4JH1TC and 4JA1TC engine is equipped with the BOSCH VP44-Type distributor injection pump.

The engine is turbocharger equipped.

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ENGINE MECHANICAL 6A – 37

REMOVAL AND INSTALLATION

Read this section carefully before performing any removal and installation procedure. This section gives you important points as well as the order of operation. Be sure that you understand everything in this section before you begin.

Removal

P1010011

1. Battery

1) Disconnect the battery cable and the grounding cable from the battery terminals.

2) Remove the battery clamp. Take care not to accidentally short the battery with the wrench or some other tool.

3) Remove the battery.

4) Disconnect the battery cable at the starter motor and the ground cable at the cylinder body.

2. Engine Hood

Apply setting marks to the engine hood and the engine hood hinges before removing the engine hood. This will facilitate reinstallation of the engine hood to its original position.

3. Supporting the Vehicle

1) Jack up the vehicle.

2) Place chassis stands at the front and the rear of the vehicle.

4. Under cover (for 4x4 model)

5. Rear propeller shaft

1) Remove the propeller shaft flange yoke at the rear differential.

2) Remove the center bearing retainer bolts.

3) Remove the propeller shaft together with the center bearing from the transmission mainshaft spline.

F06R300006

P1010002

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6A – 38 ENGINE MECHANICAL

6. Front propeller shaft (for 4x4 model)

Remove the spline yoke flange bolt at the transfer output shaft.

Do not allow the spline yoke to fall away from the front propeller shaft.

If the spline yoke should fall away from the front propeller shaft, align the setting marks on the spline yoke and the propeller shaft to reassemble the two marks. The setting marks are punched circles approx. 3mm (0.12 in) in diameter.

7. Clutch slave cylinder (for M/T model)

8. ATF pipe (for A/T model) 9 Shift control cable (for A/T model)

10. Transmission sensor harness

Remove the vehicle speed sensor connector, inhibitor switch connector (A/T), ATF temperature sensor connector, back up light switch connector (M/T) from transmission.

11. Breather hose (for A/T model)

12. Transmission shift lever (for M/T model)

Remove the shift lever from the floor.

13. Transfer shift lever (for 4x4 model)

Remove the shift lever from the floor.

14. Transmission member

1) Support the transmission with the transmission jack.

2) Remove the transmission member mounting bolts fixing the transmission member to the chassis frame.

15. Torque converter bolt (for A/T model)

1) Remove the under cover under the torque converter housing.

2) Rotate the flywheel by using tire lever or some other tool, and then remove the torque converter bolts.

16. Transmission coupling bolt

1) Support the engine with the garage jack.

2) Use the jack to slightly lower the transmission.

3) Remove the transmission coupling bolts.

17. Transmission (and transfer)

Separate the transmission (and transfer) from the engine.Take care not to damage the transmission, the engine, and their related parts..

F06R300007

P1010025

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ENGINE MECHANICAL 6A – 39

18. Radiator

1) Drain the engine coolant.

2) Remove the reservoir hose.

3) Remove the upper and lower hose.

4) Remove the fan guide.

5) Remove the radiator.

19. Fan

P1010034

20. Air cleaner

1) Remove the MAF sensor connector (4JA1TC/4JH1TC) from air cleaner duct.

2) Remove the air cleaner duct and the air cleaner box from engine room.

3) Remove the two air ducts from inter cooler (4JA1TC/4JH1TC).

21. Power Steering Pump

Loosen the power steering pump adjust plate bolt, then remove the power steering pump assembly. Place the power steering pump assembly along with piping on the body side.

22. Air conditioner compressor

1) Remove air compressor magnet connector.

2) Remove the air conditioner compressor. Place the air conditioner compressor along with piping on the body side.

23. Engine Control Cable

Remove the engine control cable from its bracket (4JA1TC/4JH1TC) or the injection pump (4JA1T(L)).

24. Vacuum Piping

Remove the vacuum pipe from the vacuum pump, the EGR valve, injection pump FICD (4JA1T(L)).

25. Engine Harn ess

1) Remove following connectors from engine.

• TPS connector

• Oil pressure switch connector

• Thermo switch connector

• Injection pump connector

• Engine earth

• Thermometer unit connector

• TDC sensor

2) Remove the clips fixing engine harness.

P1010009

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6A – 40 ENGINE MECHANICAL

140R300001

26. Fuel Hose

Remove the fuel hose from the fuel filter (Except EURO III).

RTW46ASH000501

Remove the fuel hose from injection pump (EURO III only).

27. Exhaust Pipe

Remove the front exhaust pipe bolts and separate the exhaust manifold and the front exhaust pipe.

28. Engine Assembly

1) Remove two right side engine foot bolts.

2) Remove two left side engine mount bolts.

3) Use the hoist to lift the engine from the engine compartment.

Installation

To reassemble, follow the removal steps in the reverse order.

022R300002

F06R300008

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ENGINE MECHANICAL 6A – 41

Coolant Replenishment

Warning: When the coolant is heated to a high temperature, be

sure not to loosen or remove the rediator cap. Otherwise you might get scalded by hot vapor or

boiling water. To open the radiator cap, put a piece of thick cloth on

the cap and loosen the cap slowly to reduce the pressure when the coolant has become cooler.

1. Open rediator cap pour coolant up to filler neck

2. Pour coolant into reservoir tank up to "MAX" line

3. Tighten radiator cap and start the engine. After idling for 2 to 3 minutes, stop the engine and reopen radiator cap. If the water level is lower, replenish.

4. After replenish the coolant tighten radiator cap, warm up the engine at about 2000 rpm. Set heater adjustment to the highest temperature position, and let the coolant circulate also into heater water system.

5. Check to see the thermometer, continuously idling 5 minutes and stop the engine.

6. When the engine has been cooled, check filler neck for water level and replenish if required. Should extreme shortage of coolant is found, check the coolant system and reservoir tank hose for leakage.

7. Pour coolant into the reservoir tank up to "MAX" line.

Coolant Capacity lit (US/UK gal)

4JA1 / TC 9.4 (2.5 / 2.1)

4JH1TC

M/T: 10.1 (2.7 / 2.2)

A/T: 10.0 (2.6 / 2.2)

Engine Warm-Up

After completing the required maintenance procedures, start the engine and allow it to idle until it is warm.

Check the following:

1. Engine idling speed.

2. Engine noise level.

3. Engine lubricating system and cooling system. Carefully check for oil and coolant leakage.

4. Clutch engagement.

5. Transmission operation.

6. Indicator warning light operation.

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6A – 42 ENGINE MECHANICAL

ENGINE REPAIR KIT

RTW36ALF000601

Removal Steps

1. Cylinder head gasket

2. Head cover gasket

3. Head cover cap nut gasket

4. Drain cock gasket

5. Crankshaft rear oil seal

6. Gear case gasket

7. Oil pan drain plug gasket

8. Oil pan gasket

9. Oil filter gasket

10. Joint bolt gasket

11. Vacuum pump gasket

12. Water pump O-ring

13. Water outlet pipe gasket

14. Intake pipe gasket

15. Thermostat housing gasket

16. Intake manifold gasket

17. Exhaust manifold gasket

18. Nozzle holder O-ring

19. Nozzle holder gasket

20. Crankshaft front oil seal

NOTE Discard all O-rings, gaskets, and seals removed at disassembly and replace them with new ones. Reuse of

these parts will result in oil, water, and gas leakage.

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ENGINE MECHANICAL 6A – 43

ENGINE OVERHAUL

REMOVAL

EXTERNAL PARTS

RTW36AMF000401

Removal Steps

1. Clutch Assembly or Flex Plate

2. Intake Pipe and Throttle Body 3-1. EGR Pipe 3-2. EGR cooler (EURO III model only)

4. EGR Valve

5. Oil Level Gauge

6. Fuel Filter Assembly (Except EURO III)

7. Fuel Filter Bracket (Except EURO III)

8. Fuel Injection Pipe with Clip

9. Power Steering Oil Pump Bracket

10. Intake Manifold

11. Engine Mounting Bracket and Foot

12. Injection Pump Cover

13. Injection Pump

14. Starter Motor

15. Oil Pressure Warning Switch

16. Fuel Leak Off Pipe

17. Oil Cooler Water Pipe

18. Cooling Fan Pulley

19. Heat Protector

20. Catalytic Converter

21. Turbocharger

22. Compressor Bracket

23. Vacuum Pump Oil Return Hose

24. Generator and Adjusting Plate

25. Water Inlet Pipe

26. Generator Bracket

27. Oil Cooler with Oil Filter

28. Exhaust Manifold

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6A – 44 ENGINE MECHANICAL

Removal

1. Clutch Assembly or Flex Plate

Remove the clutch assembly or the flex plate.

4JA1L

RTW46ASH000801

2. Intake Pipe and Throttle Body (4JA1TC/4JH1TC only)

1) Loosen hose clamp between turbocharger and intake duct.

2) Remove the rubber hose.

3) Remove the intake pipe and the throttle body. (4JA1TC/4JH1TC only)

RTW36ASH000201

4JA1L

025R100008

3-1. EGR Pipe

1) Remove two bolts from the exhaust manifold.

2) Remove two nuts from the EGR valve adapter.

3) Remove the EGR pipe with gaskets.

RTW36ASH000301

3-2. EGR Cooler (EURO III model only)

4JA1TC/4JH1TC

4JH1TC

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ENGINE MECHANICAL 6A – 45

4JA1L

RTW46ASH001001

4. EGR Valve

1) Remove four nuts and remove the EGR valve assembly from the intake manifold.

2) Remove four bolts and remove the adapter from the EGR valve assembly.

4JA1TC

RTW46ASH000901

5. Oil Level Gauge

1) Disconnect PCV hose.

2) Remove two bolts and remove the engine oil level gauge.

6. Fuel Filter Assembly (Except EURO III model)

1) Disconnect fuel hose.

2) Remove two bolts and remove the fuel filter.

7. Fuel Filter Bracket (Except EURO III model)

Remove three bolts and remove the fuel filter bracket with leak pipe.

4JH1TC

RTW36ASH001201

8. Fuel Injection Pipe with Clip

1) Loosen the injection pipe sleeve nuts at pump side and nozzle side. Do not apply excessive force to the injection pipes.

2) Loosen the injection pipe clips.

3) Remove the injection pipe.

NOTE: Plug the delivery holder ports with the caps to prevent the

entry of foreign material.

9. Power Steering Oil Pump Bracket

RTW36ASH000701

10. Intake Manifold

1) Disconnect the PCV hose from the cylinder head cover.

2) Remove the intake manifold with gasket.

11. Engine Mounting Bracket and Foot

12. Injection Pump Cover

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6A – 46 ENGINE MECHANICAL

13. Injection Pump

Refer to section 6C-19 (Injection Pump)

14. Starter Motor

15. Oil Pressure Warning Switch

16. Fuel Leak Off Pipe

17. Oil Cooler Water Pipe

18. Cooling Fan Pulley

19. Heat Protector

20. Catalytic Converter

21. Turbocharger

1) Disconnect the water hose between thermostat housing cover and turbocharger.

2) Disconnect the water hose between water inlet pipe and turbocharger.

3) Remove the oil feed pipe.

4) Remove the oil return pipe.

5) Remove the turbocharger and the gasket.

NOTE: Plug the turbocharger body oil ports and water ports after

removing the turbocharger assembly to prevent the entry of foreign material.

22. Compressor Bracket

23. Vacuum Pump Oil Return Hose

24. Generator and Adjusting Plate

25. Water Inlet Pipe

26. Generator Bracket

27. Oil Cooler with Oil Filter

28. Exhaust Manifold

027R100007

037RY00001

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ENGINE MECHANICAL 6A – 47

DISASSEMBLY

INTERNAL PARTS

MAJOR COMPONENTS

Disassembly Steps-1

Water bypass hose 5.

Rocker arm shaft and rocker

Thermostat housing with thermo arm

switch 6. Push rod

Cylinder head cover 7.

Cylinder head

Injection nozzle and bracket 8.

Cylinder head gasket

011R300001

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6A – 48 ENGINE MECHANICAL

RTW46ALF000101

Disassembly Steps-2

9. Crankshaft damper pulley

10. Timing gear case cove

11. Water pump

12. Idle gear "B" and shaft

13. Idle gear "A"

14. Idle gear shaft

15. Crankshaft timing gear

16. Injection pump

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ENGINE MECHANICAL 6A – 49

014R300005

Disassembly Steps-3

17. Flywheel 27. Piston and connecting rod with

18. Crank case upper bearing

19. Oil pump with oil pipe 28. Crankshaft bearing cap with

20. Camshaft timing gear lower bearing

21. Camshaft thrust plate 29. Crankshaft thrust bearing

22. Camshaft 30. Crankshaft

23. Timing gear case 31. Crankshaft upper bearing

24. Cylinder body rear plate 32. Tappet

25. Piston cooling oil jet 33. Crankshaft rear oil seal

26. Connecting rod bearing cap with 34. Cylinder body lower bearing

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6A – 50 ENGINE MECHANICAL

Disassembly

1. Water Bypass Hose

2. Thermostat Housing with Thermo Switch

3. Cylinder Head Cover

4. Injection Nozzle and Bracket

1. Remove the injection nozzle bracket bolts.

2. Use the injection nozzle remover and the sliding hammer to remove the injection nozzle together.

Injection Nozzle Remover: 5-8840-2723-0 Sliding Hammer: 5-8840-0019-0

5. Rocker Arm Shaft and Rocker Arm

Loosen the rocker arm shaft bracket bolts in numerical order a little at a time.

Note: Failure to loosen the rocker arm shaft bracket bolts in

numerical order a little at a time will adversely affect the rocker arm shaft.

6. Push Rod

7. Cylinder Head

Loosen the cylinder head bolts in numerical order a little at a time.

Note: Failure to loosen the cylinder head bolts in numerical

order a little at a time will adversely affect the cylinder head lower surface.

8. Cylinder Head Gasket

9. Crankshaft Damper Pulley

011R100002

011RY00005

011RY00006

011RY00007

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ENGINE MECHANICAL 6A – 51

10. Timing Gear Case Cover

The timing gear case is tightened together with the injection pump at the 6 points indicated by the arrows in the illustration.

11. Water Pump

12. Idle Gear B and shaft

Before removing the idle gear B, install bolt (M6,L=30) to the hole marked with an arrow in the illustration to hold the scissor gear in place.

13. Idler Gear "A"

1. Measure the camshaft timing gear backlash and the crankshaft timing gear backlash before removing the idler gear.

2. Measure the idler gear end play before removing the idler gear.

NOTE: Refer to the following items for details on the backlash

and end play measurement procedures.

Timing Gear Backlash Measurement

1. Set a dial indicator to the timing gear to measured. Hold both the gear to be checked and the adjusting gear stationary.

2. Move the gear to be checked as far as possible to both the right and the left. Take the dial indicator reading. If the measured value exceeds the specified limit, the timing gear must be replaced.

Timing Gear Backlash mm (in)

Standard Limit

0.10 - 0.17 (0.0039 - 0.0067) 0.30 (0.012)

020L200006

020L200020

020RY00019

020RY00020

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6A – 52 ENGINE MECHANICAL

RTW36ASH000801

Idler Gear "A" End Play Measurement

Insert a feeler gauge between the idler gear and the thrust collar to measure the gap and determine the idler gear end play.

If the measured value exceeds the specified limit, the thrust collar must be replaced.

Idler Gear End Play mm (in)

Standard Limit

0.07 (0.0028) 0.2 (0.0079)

4JA1T(L)

RTW86ASH002301

14. Idle Gear Shaft

15. Crankshaft Timing Gear

4JA1TC/4JH1TC

RTW36ASH001301

16. Injection Pump

1. Remove the injection pump cover (4JA1TC/4JH1TC only).

2. Remove the injection pump bracket.

3. Pull the injection pump along with the injection pump timing gear free toward the rear of the engine.

NOTE: Plug the injection pump delivery ports with the caps to

prevent the entry of foreign material.

17. Flywheel

Loosen the flywheel bolts in numerical order a little at a time. Use the gear stoper to stop the flywheel gear. Gear stoper: 5-8840-0214-0

18. Crank Case

19. Oil Pump With Oil Pipe

015RY00001

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ENGINE MECHANICAL 6A – 53

20. Camshaft Timing Gear

1. Use a dial indicator to measure the camshaft end play. This must be done before removing the camshaft gear. If the camshaft end play exceeds the specified limit, the thrust plate must be replaced.

Camshaft End Play mm (in)

Standard Limit

0.050 - 0.114

(0.002 - 0.0044)

0.20

(0.008)

2. Remove the camshaft timing gear bolt from the camshaft.

Note: Hold the camshaft stationary to prevent the camshaft

from turning.

3. Remove the sensor rotor plate.

4. Use the universal puller to pull out the camshaft timing gear. Universal Puller: 5-8521-0002-0

5. Remove the thrust plate.

21. Camshaft Thrust Plate

22. Camshaft

Jiggle the camshaft with your hand as you pull it free from the front of the engine.

23. Timing Gear Case

24. Cylinder Body Rear Plate

25. Piston Cooling Oil Jet

The oiling jet uses thin steel tubing which is easily bent. Accidental contact between the oiling jet and the cylinder

body, piston, or a tool will damage the oiling jet. Never attempt to repair a damaged oiling jet. Replace it

with a new one.

014RT0001

901R100008

014RY00019

052RY00001

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6A – 54 ENGINE MECHANICAL

26. Connecting Rod Bearing Cap with Lower Bearing

If the connecting rod lower bearings are to be reinstalled, mark their fitting positions by tagging each bearing with the cylinder number from which it was removed.

27. Piston and Connecting Rod with Upper Bearing

1. Remove carbon deposits from the upper portion of the cylinder wall with a scraper before removing the piston and connecting rod.

2. Move the piston to the top of the cylinder and tap it with a hammer grip or a similar object from the connecting rod lower side to drive it out.

RTW36ASH001501

If the connecting rod upper bearings are to be reinstalled, mark their fitting positions by tagging each bearing with the cylinder number from which it was removed.

28. Crankshaft Bearing Cap with Lower Bearing

1. Measure the crankshaft end play at the center journal of the crankshaft. Do this before removing the crankshaft bearing caps. If the measured value exceeds the specified limit, the crankshaft thrust bearing must be replaced.

Crankshaft End Play mm (in)

Standard Limit

0.10 (0.004) 0.30 (0.012)

014LX056

015LX018

015RY00002

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ENGINE MECHANICAL 6A – 55

2. Loosen the crankshaft bearing cap bolts in numerical order a little at a time. If the crankshaft bearings are to be reinstalled, mark their fitting positions by tagging each bearing with the cylinder number from which it was removed.

29. Crankshaft Thrust Bearing

30.Crankshaft

31. Crankshaft Upper Bearing

If the crankshaft upper bearings are to be reinstalled, mark their fitting positions by tagging each bearing with the cylinder number from which it was removed.

32. Tappet

If the tappets are to be reinstalled, mark their fitting positions by tagging each tappet with the cylinder number from which it was removed.

33. Crankshaft Rear Oil Seal

• With the oil seal pushed in deep, install the special

tool as shown in the illustration and remove the oil seal. Oil Seal Remover: 5-8840-2360-0

34. Cylinder Body

015RY00003

015RY00004

015RY00005

015LV002

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6A – 56 ENGINE MECHANICAL

MINOR COMPONENTS

ROCKER ARM SHAFT AND ROCKER ARM

Disassembly Steps

1. Rocker arm shaft snap ring 5. Rocker arm shaft spring

2. Rocker arm 6. Rocker arm shaft snap ring

3. Rocker arm shaft bracket 7. Rocker arm shaft

4. Rocker arm

Disassembly

1. Rocker Arm Shaft Snap Ring

2. Rocker Arm

3. Rocker Arm Shaft Bracket

1. Use a pair of pliers to remove the snap rings.

2. Remove the rocker arms.

3. Remove the rocker arm shaft brackets. If the rocker arms and rocker arm shaft brackets are to be reinstalled, mark their installation positions by tagging each rocker arm and rocker arm shaft bracket with the cylinder number from which it was removed.

4. Rocker Arm

5. Rocker Arm Shaft Spring

6. Rocker Arm Shaft Snap Ring

7. Rocker Arm Shaft

011RY00009

011RY00010

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ENGINE MECHANICAL 6A – 57

CYLINDER HEAD

RTW46ALF001201

Disassembly Steps

Intake manifold 6. Intake and exhaust valve

Intake manifold gasket 7. Valve stem oil seal

Split collar 8. Valve spring lower seat

Valve spring upper seat 9. Cylinder head

Valve spring

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6A – 58 ENGINE MECHANICAL

Disassembly

1. Intake Manifold

2. Intake Manifold Gasket

3. Split Collar

1. Place the cylinder head on a flat wooden surface.

2. Use the spring compressor to remove the split collars. Do not allow the valve to fall from the cylinder head. Spring Compressor: 9-8523-1423-0

4. Valve Spring Upper Seat

5. Valve Spring

6. Intake and Exhaust Valve

If the intake and exhaust valves are to be reinstalled, mark their installation positions by tagging each valve with the cylinder number from which it was removed.

If the intake and exhaust valves are to be replaced, the valve guides must also be replaced.

7. Valve Stem Oil Seal

8. Valve Spring Lower Seat

9. Cylinder Head

011RY00011

011LX022

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ENGINE MECHANICAL 6A – 59

PISTON AND CONNECTING ROD

RTW46ALF000301

Disassembly Steps

Connecting rod bearing 4. Piston pin

Piston ring 5. Connecting rod

Piston pin snap ring 6. Piston

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6A – 60 ENGINE MECHANICAL

RTW36ASH001501

Disassembly

1. Connecting Rod Bearing

If the connecting rod bearings are to be reinstalled, mark their fitting positions by tagging each bearing with the cylinder number from which it was removed.

015RW041

2. Piston Ring

1. Clamp the connecting rod in a vise. Take care not to damage the connecting rod.

2. Use a piston ring replacer to remove the piston rings. Piston Ring Replacer Do not attempt to use some other tool to remove the

piston rings. Piston ring stretching will result in reduced piston ring tension.

3. Piston Pin Snap Ring

Use a pair of pliers to remove the piston pin snap rings.

RTW36ASH001601

4. Piston Pin

5. Connecting Rod

6. Piston

Tap the piston pin out with a hammer and a brass bar. If the pistons and piston pins are to be reinstalled, mark

their installation positions by tagging each piston and piston pin with the cylinder number from which it was removed.

F06MV015

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ENGINE MECHANICAL 6A – 61

INSPECTION AND REPAIR

Make the necessary adjustments, repairs, and part replacements if excessive wear or damage is discovered during inspection.

CYLINDER HEAD

Cylinder Head Lower Face Warpage

1. Use a straight edge and a feeler gauge to measure the four sides and the two diagonals of the cylinder head lower face.

2. The cylinder head lower surface warpage is more than the limit, it should be replaced.

Cylinder Head Lower Face Warpage (A-F) mm (in)

Standard Limit

0.05

(0.002) or less

0.20

(0.0079)

NOTE:

The cylinder head lower face cannot be reground.

Cylinder Head Height (H) (Reference) mm (in)

Standard

91.95 – 92.05

(3.620 – 3.624)

Positive Crankcase Ventilation (PCV) Valve

1. Remove PCV valve assembly from cylinder head cover.

2. Inspect the diaphragm for broken.

3. Inspect the spring for broken or weaken.

4. If find any abnormal condition, replace the PCV valve assembly.

011RY00012

011RY00013

011RY00014

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6A – 62 ENGINE MECHANICAL

Manifold Fitting Face Warpage

Use a straight edge and a feeler gauge to measure the manifold cylinder head fitting face warpage. Regrind the manifold cylinder head fitting surfaces if the measured values are greater than the specified limit but less than the maximum grinding allowance. If the measured values exceed the maximum grinding allowance, the cylinder head must be replaced.

Manifold Fitting Face Warpage

mm (in)

Standard Limit

Maximum Grinding

Allowance

0.05

(0.002) or less

0.20

(0.008)

0.40

(0.016)

Exhaust Manifold Warpage

Use a straight edge and a feeler gauge to measure the manifold cylinder head fitting face warpage. If the measured values exceed the specified limit, the manifold must be replaced.

Exhaust Manifold Warpage mm (in)

Standard Limit

0.05 (0.002) or less 0.20 (0.008)

Valve Stem and Valve Guide Clearance

Measuring Method-I

1. With the valve stem inserted in the valve guide, set the dial indicator needle to "0".

2. Move the valve head from side to side.

Read the dial indicator. Note the highest dial indication.

If the measured values exceed the specified limit, the valve and the valve guide must be replaced as a set.

Valve Stem Clearance mm (in)

Standard Limit

Intake Valve

0.039 - 0.071

(0.0015 - 0.0028)

0.200

(0.008)

Exhaust Valve

0.064 - 0.096

(0.0025 - 0.0038)

0.250

(0.0098)

027RY00001

027RY00002

011RY00022

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ENGINE MECHANICAL 6A – 63

Measuring Method-II

1. Measure the valve stem outside diameter.

Refer to the Item "Valve Stem Outside Diameter".

2. Use a caliper calibrator or a telescoping gauge to measure the valve guide inside diameter.

Valve Guide Replacement

Valve Guide Removal

Use a hammer and the valve guide replacer to drive out the valve guide from the cylinder head lower face. Valve Guide Replacer: 9-8523-1212-0

Valve Guide Installation

1. Apply engine oil to the valve guide outer circumference.

2. Attach the valve guide installer to the valve guide.

3. Use a hammer to drive the valve guide into position from the cylinder head upper face.

Valve Guide Replacer: 9-8523-1212-0

4. Measure the height of the valve guide upper end from the upper face of the cylinder head.

Valve Guide Upper End Height (H) (Reference) mm (in)

12.8-13.2 (0.50-0.52)

NOTE:

If the valve guide has been removed, both the valve and the valve guide must be replaced as a set.

011LX029

011RY00024

011RY000025

011RY00023

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6A – 64 ENGINE MECHANICAL

Valve Stem Outside Diameter

Measure the valve stem diameter at three points. If the measured value is less than the specified limit, the valve and the valve guide must be replaced as a set.

Valve Stem Outside Diameter mm (in)

Standard Limit

Intake Valve

7.946 - 7.961

(0.3128 - 0.3134)

7.880

(0.3102)

Exhaust Valve

7.921 - 7.936

(0.3119 - 0.3124)

7.850

(0.3090)

Valve Thickness

Measure the valve thickness. If the measured value is less than the specified limit, the valve and the valve guide must be replaced as a set.

Intake and Exhaust Valve Thickness mm (in)

Standard Limit

4JA1T (L) 1.8 (0.07) 1.5 (0.06)

Inlet 1.34 (0.053)

JA1TC,

4JH1TC

Exhaust 1.36 (0.054)

1.1 (0.043)

Valve Depression

1. Install the valve (1) to the cylinder head (2).

2. Use a depth gauge or a straight edge with steel rule to measure the valve depression from the cylinder head lower surface.

If the measured value exceeds the specified limit, the valve seat insert must be replaced.

Valve Depression mm (in)

Standard Limit

4JA1T(L) 0.72 (0.028) 1.28 (0.050)

4JA1TC, 4JH1TC 1.17 (0.046) 1.67 (0.066)

011LX027

014RY00020

014RY00021

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ENGINE MECHANICAL 6A – 65

Valve Contact Width

1. Check the valve contact faces for roughness and unevenness. Make smooth the valve contact surfaces.

2. Measure the valve contact width.

If the measured value exceeds the specified limit, the valve seat insert must be replaced.

Valve Contact Width mm (in)

Standard Limit

Intake 1.7 (0.067) 2.2 (0.087)

Exhaust 2.0 (0.079) 2.5 (0.098)

Valve Seat Insert Replacement

Valve Seat Insert Removal

1. Arc weld the entire inside circumference (1) of the valve seat insert (2).

2. Allow the valve seat insert to cool for a few minutes.

This will invite contraction and make removal of the valve seat insert easier.

3. Use a screwdriver (3) to pry the valve seat insert free.

Take care not to damage the cylinder head (4).

4. Carefully remove carbon and other foreign material from the cylinder head insert bore.

014RY00027

011LX039

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6A – 66 ENGINE MECHANICAL

Valve Seat Insert Installation

1. Carefully place the attachment (1) (having a smaller outside diameter than the valve seat insert) on the valve seat insert (2).

NOTE:

The smooth side of the attachment must contact the valve seat insert.

2. Use a bench press (3) to gradually apply pressure to the attachment and press the valve seat insert into place.

NOTE:

Do not apply an excessive amount of pressure with the bench press. Damage to the valve seat insert will result.

Valve Seat Insert Correction

1. Remove the carbon from the valve seat insert surface.

2. Use a valve cutter (15°, 45°, and 75° blades) to minimize scratches and other rough areas. This will bring the contact width back to the standard value.

Remove only the scratches and rough areas. Do not cut away too much. Take care not to cut away unblemished areas of the valve seat surface.

Valve Seat Angle Degree

NOTE:

Use an adjustable valve cutter pilot.

Do not allow the valve cutter pilot to wobble inside the valve guide.

3. Apply abrasive compound to the valve seat insert surface.

4. Insert the valve into the valve guide.

5. Turn the valve while tapping it to fit the valve seat insert.

6. Check that the valve contact width is correct.

7. Check that the valve seat insert surface is in contact with the entire circumference of the valve.

011LX063

014RY00026

011LX037

011LX038

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ENGINE MECHANICAL 6A – 67

Valve Spring Free Height

Use a vernier caliper to measure the valve spring free height. If the measured value is less than the specified limit, the valve spring must be replaced.

Spring Free Height mm (in)

Standard Limit

4JA1T (L)

4JA1TC,

4JH1TC

Single spring 48.0 (1.89) 47.1 (1.85)

Valve Spring Squareness

Use a surface plate and a square to measure the valve spring squareness. If the measured value exceeds the specified limit, the valve spring must be replaced.

Spring Squareness mm (in)

Limit

4JA1T (L)

4JA1TC,

4JH1TC

Single spring 1.7 (0.067)

Valve Spring Tension

Use a spring tester to measure the valve spring tension. If the measured value is less than the specified limit, the valve

spring must be replaced.

Valve Spring Tension N (kg/lb)

Compressed

Height

Standard Limit

JA1T (L)

4JA1TC,

4JH1TC

Single spring

38.9mm (1.53in)

296.0

(30.2/66.4)

257.7

(26.3/57.9)

011LX024

014RY00025

011LX026

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6A – 68 ENGINE MECHANICAL

ROCKER ARM SHAFT AND ROCKER ARM

Rocker Arm Shaft Run-Out

1. Place the rocker arm shaft on a V-block.

2. Use a dial indicator to measure the rocker arm shaft central portion run-out.

If the run-out is very slight, correct the rocker arm shaft run-out with a bench press. The rocker arm must be at cold condition.

If the measured rocker arm shaft run-out exceeds the specified limit, the rocker arm shaft must be replaced.

Rocker Arm Shaft Run-Out mm (in)

Limit

0.3 (0.012)

Rocker Arm Shaft Outside Diameter

Use a micrometer to measure the rocker arm fitting portion outside diameter. If the measured value is less than the specified limit, the rocker arm shaft must be replaced.

Rocker Arm Shaft Outside Diameter mm (in)

Standard Limit

18.98–19.00 (0.747–0.748) 18.90 (0.744)

Rocker Arm Shaft and Rocker Arm Clearance

1. Use either a vernier caliper or a dial indicator to measure

the rocker arm inside diameter.

Rocker Arm Inside Diameter mm (in)

Standard Limit

19.010–19.030 (0.748–0.749)

19.100 (0.752)

2. Measure the rocker arm shaft outside diameter. If the measured value exceeds the specified limit, replace either the rocker arm or the rocker arm shaft.

Rocker Arm Shaft and Rocker Arm Clearance mm (in)

Standard Limit

0.01–0.05

(0.0004–0.0020)

0.20 (0.008)

015LX009

014RY00024

015LX008

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ENGINE MECHANICAL 6A – 69

3. Check that the rocker arm oil port is free of obstructions. If necessary, use compressed air to clean the rocker arm

oil port.

Rocker Arm Correction

Inspect the rocker arm valve stem contact surfaces for step wear (1) and scoring (2).

If the contact surfaces have light step wear or scoring, they may be honed with an oil stone.

If the step wear or scoring is severe, the rocker arm must be replaced.

CYLINDER BODY

Cylinder Body Upper Face Warpage

1. Remove the cylinder body dowel.

2. Remove the cylinder liner. Refer to "Cylinder Liner Replacement".

3. Use a straight edge (1) and a feeler gauge (2) to measure

the four sides and the two diagonals of the cylinder body upper face.

If the measured values exceeds the limit, the cylinder body must be replaced.

Cylinder Body Upper Face Warpage mm (in)

Standard Limit

0.05 (0.002) or less 0.20 (0.008)

Cylinder Body Height (H) (Reference) mm (in)

Standard

4JA1T(L), 4JA1TC : 244.945-245.055 (9.6435-9.6478)

4JH1TC : 269.945-270.055 (10.6277-10.6320)

4. Reinstall the cylinder liner. Refer to "Cylinder Liner Replacement".

5. Reinstall the cylinder body dowel.

014RY00024

012R100001

012RY00009

014RY00023

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6A – 70 ENGINE MECHANICAL

Cylinder Liner Bore Measurement

Use a cylinder indicator to measure the cylinder bore at measuring point (1) in the thrust (2-2) and axial (3-3) directions of the crankshaft.

Measuring Point (1): 20 mm (0.79 in) If the measured value exceeds the specified limit, the cylinder

liner must be replaced.

Cylinder Liner Bore mm (in)

Standard Limit

4JA1T(L), 4JA1TC 93.00 (3.6614) 93.08 (3.6646)

4JH1TC 95.40 (3.7559) 95.48 (3.7590)

NOTE:

The inside of the dry type cylinder liner is chrome plated. It cannot be rebored or honed.

If the inside of the cylinder liner is scored or scorched, the cylinder liner must be replaced.

Cylinder Liner Projection Inspection

1. Hold a straight edge along the top edge of the cylinder liner

to be measured.

2. Use a feeler gauge to measure each cylinder liner

projection.

Cylinder Liner Projection mm (in)

Standard

0-0.1 (0-0.004)

The difference in the cylinder liner projection height between any two adjacent cylinders must not exceed 0.03 mm (0.0012 in).

Cylinder Liner Replacement

Cylinder Liner Removal

1. Insert the cylinder liner remover (1) into the cylinder body

(from the lower side of the cylinder body) until it makes firm

contact with the cylinder liner. Cylinder Liner Remover : 5-8840-2039-0 (4JA1L/TC) : 5-8840-2304-0 (4JH1TC)

2. Use a bench press (2) to slowly force the cylinder liner from the cylinder body.

NOTE:

Take care not to damage the cylinder body upper face during the cylinder liner removal procedure.

3. Measure the cylinder body upper face warpage.

Refer to "Cylinder Body Upper Face Warpage".

012RY00010

012LX016

012RY00012

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ENGINE MECHANICAL 6A – 71

Cylinder Liner Grade Selection

Subtract the average cylinder body bore from the average cylinder liner outside diameter to obtain the fitting interference.

Fitting Interference

mm (in)

Standard

-0.0010*-0.019 (-0.00004*-0.00075)

* A minus (-) value indicates that the cylinder body bore is smaller than the liner outside diameter.

Cylinder Body Bore Measurement

1. Take measurements at measuring point (1) across positions 1-1 and 2-2.

Measuring Point (1): 4JA1T(L), 4JA1TC : 13,48,83,118,153 mm

(0.51,1.89,3.27,4.65,6.02 in) 4JH1TC : 18,53,88,123,158 mm (0.71,2.09,3.46,4.84,6.22

in)

Cylinder Liner Grade Selection and Standard Fitting Interference

Accurately measured fitting interference and proper cylinder liner grade selection are extremely important.

If the cylinder liner fitting interference is too small, engine cooling efficiency will be adversely affected.

If the cylinder liner fitting interference is too large, it will be difficult to insert the cylinder liner into the cylinder body.

012RY00013

012RY00014

012R300001

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6A – 72 ENGINE MECHANICAL

012RY00022

A mark was stamped on the upper side of the cylinder block during production to indicate the correct liner.

The liner grade (i.e.1.2.3.4) is indicated in metal stamp.

Cylinder Liner Grade

4JA1T (L), 4JA1TC mm (in)

Liner

Outside

Grade

Cylinder Body

Bore Diameter

Liner Outside

Diameter

Liner Bore

Grade

Service Liner Bore Measurement

AX 93.035-93.050 (3.6628-3.6634)

95.001-95.010

(3.7402-3.7405)

95.011-95.020

(3.7406-3.7409)

CX 93.051-93.066 (3.6634-3.6640)

AX 93.035-93.050 (3.6628-3.6634)

95.011-95.020

(3.7406-3.7409)

95.021-95.030

(3.7410-3.7413)

CX 93.051-93.066 (3.6634-3.6640)

AX 95.035-93.050 (3.6628-3.6634)

95.021-95.030

(3.7410-3.7413)

95.031-95.040

(3.7414-3.7417)

CX 93.051-93.066 (3.6634-3.6640)

AX 93.035-93.050 (3.6628-3.6634)

95.031-95.040

(3.7414-3.7417)

95.041-95.050

(3.7418-3.7421)

CX 93.051-93.066 (3.6634-3.6640)

4JH1TC mm (in)

Liner

Outside

Grade

Cylinder Body

Bore Diameter

Liner Outside

Diameter

Liner Bore

Grade

Service Liner Bore Measurement

AX 95.435-95.450 (3.7573-3.7579)

97.001-97.010

(3.8189-3.8193)

97.011-97.020

(3.8193-3.8197)

CX 95.451-95.466 (3.7579-3.7585)

AX 95.435-95.450 (3.7573-3.7579)

97.011-97.020

(3.8193-3.8197)

97.021-97.030

(3.8197-3.8200)

CX 95.451-95.466 (3.7579-3.7585)

AX 95.435-95.450 (3.7573-3.7579)

97.021-97.030

(3.8197-3.8200)

97.031-97.040

(3.8200-3.8205)

CX 95.451-95.466 (3.7579-3.7585)

AX 95.435-95.450 (3.7573-3.7579)

97.031-97.040

(3.8200-3.8205)

97.041-97.050

(3.8205-3.8209)

CX 95.451-95.466 (3.7579-3.7585)

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ENGINE MECHANICAL 6A – 73

Cylinder Liner Installation

1. Cylinder Liner Installation Using The Special Tool

1. Use new kerosene or diesel oil to thoroughly clean the cylinder liners and bores.

2. Use compressed air to blow-dry the cylinder liner and bore surfaces.

NOTE:

All foreign material must be carefully removed from the cylinder liner and the cylinder bore before installation.

3. Insert the cylinder liner (1) into the cylinder body (2) from the top of the cylinder body.

4. Set the cylinder liner installer (3) to the top of the cylinder liner.

Cylinder Liner Installer : 5-8840-2040-0 (4JA1L/TC) : 5-8840-2313-0 (4JH1TC)

5. (3) is directly beneath the bench press shaft center (4).

NOTE:

Check that the cylinder liner is set perpendicular to the bench press and that there is no wobble.

6. Use the bench press to apply a seating force of 4,900 N (500 kg/1,100 Ib) to the cylinder liner.

7. Apply a force of 24,500 N (2,500 kg/5,500 Ib) to fully seat the cylinder liner.

8. After installing the cylinder liner, measure the cylinder liner projection.

Refer to "Cylinder Liner Projection Inspection".

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6A – 74 ENGINE MECHANICAL

Piston Grade Selection

Measure the cylinder liner bore after installing the cylinder liner. Then select the appropriate piston grade for the installed cylinder liner.

1. Measure the cylinder liner bore. Refer to "Cylinder Liner Bore Measurement"

Cylinder Liner Bore (Service Part) Grade mm (in)

Grade Bore measurement

93.035-95.050

(3.6628-3.6634)

4JA1T(L)

4JA1TC

93.051-95.066

(3.6634-3.6640)

95.435-95.450

(3.7573-3.7579)

4JH1TC

95.451-95.466

(3.7579-3.7585)

NOTE:

It is most important that the correct piston grade be used. Failure to select the correct piston grade will result in engine failure. Always measure the cylinder bore and select the correct piston grade.

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ENGINE MECHANICAL 6A – 75

2. Measure the piston diameter.

Piston Measuring Point

mm (in)

4JA1T(L)

4JA1TC

78 (3.07)

4JH1TC 70 (2.76)

Piston Grade (Service Part)

mm (in)

92.949 - 92.964

(3.6549 - 3.6600)

4JA1T(L)

4JA1TC

92.965 - 92.980

(3.6600 - 3.6606)

95.359 - 95.374

(3.7542 - 3.7548)

4JH1TC

95.375 - 95.390

(3.7548 - 3.7555)

ylinder Liner and Piston Clearance

mm (in)

4JA1T(L)

4JA1TC

0.041-0.071 (0.0016-0.0027)

4JH1TC 0.047-0.065 (0.0019-0.0026)

NOTE:

Cylinder liner kit clearances are preset. However, the cylinder liner installation procedure may result in slight decreases in cylinder liner clearances. Always measure the cylinder liner clearance after installation to be sure that it is correct.

TAPPET AND PUSH ROD

Visually inspect the tappet contact surfaces for pitting, cracking, and other abnormal conditions. The tappet must be replaced if any of these conditions are present.

Refer to the illustration at the left.

1. Normal contact

2. Cracking

3. Pitting

4. Irregular contact Uneven contact

5. Irregular contact One-sided contact

NOTE:

The tappet surfaces are spherical. Do not attempt to grind them with an oil stone or similar tool in an effort to repair the tappet. If the tappet is damaged, it must be replaced.

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6A – 76 ENGINE MECHANICAL

Tappet Outside Diameter

Measure the tappet outside diameter with a micrometer. If the measured value is less than the specified limit, the tappet

must be replaced.

appet Outside Diameter mm (in)

Standard Limit

12.97 - 12.99

(0.510 - 0.511)

12.95 (0.510)

appet and Cylinder Body Clearance

mm (in)

Standard Limit

0.01 - 0.046

(0.0004 - 0.0018)

0.10 (0.004)

Push Rod Curvature

1. Lay the push rod on a surface plate.

2. Roll the push rod along the surface plate and measure the

push rod curvature with a thickness gauge.

If the measured value exceeds the specified limit, the push rod must be replaced.

Pushrod Curvature mm (in)

Limit

0.3 (0.012)

3. Visually inspect both ends of the push rod for excessive

wear and damage. The push rod must be replaced if these conditions are discovered during inspection.

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ENGINE MECHANICAL 6A – 77

CAMSHAFT

Visually inspect the journals, the cams, the oil pump drive gear, and the camshaft bearings for excessive wear and damage. The camshaft and the camshaft bearings must be replaced if these conditions are discovered during inspection.

Camshaft Journal Diameter

Use a micrometer to measure each camshaft journal diameter in two directions (1 and 2). If the measured value is less than the specified limit, the camshaft must be replaced.

Camshaft Journal Diameter mm (in)

Standard Limit

49.945 - 49.975

(1.9663 - 1.9675)

49.60 (1.953)

Cam Height

Measure the cam height (H) with a micrometer. If the measured value is less than the specified limit, the camshaft must be replaced.

Cam Height (H) mm (in)

Standard Limit

42.016 (1.6542) 41.65 (1.640)

Camshaft Run-Out

1. Mount the camshaft on V-blocks.

2. Measure the run-out with a dial indicator. If the measured value exceeds the specified limit, the

camshaft must be replaced.

Camshaft Run-Out mm (in)

Standard Limit

0.02 (0.0008) 0.10 (0.004)

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6A – 78 ENGINE MECHANICAL

Camshaft and Camshaft Bearing Clearance

Use an inside dial indicator to measure the camshaft bearing inside diameter.

Crankshaft Bearing Inside Diameter mm (in)

Standard Limit

50.00 - 50.03

(1.968 - 1.970)

50.08 (1.972)

If the clearance between the camshaft bearing inside diameter and the journal exceeds the specified limit, the camshaft bearing must be replaced.

Camshaft Bearing Clearance mm (in)

Standard Limit

0.055 (0.0022) 0.12 (0.0047)

Camshaft Bearing Replacement

Camshaft Bearing Removal

1. Remove the cylinder body plug plate.

2. Use the bearing replacer to remove the camshaft bearing. Bearing Replacer: 5-8840-2038-0

Camshaft Bearing Installation

1. Align the bearing oil holes with the cylinder body oil holes.

2. Use the replacer to install the camshaft bearing. Bearing Replacer: 5-8840-2038-0

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Isuzu 4JA1, 4JH1 Workshop Manual

Specifications and Main Features

Frequently Asked Questions

User Manual