piston ISUZU TF SERIES 2004 Service Manual

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 exhaustAdjust 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

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

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
Engine weight (dry) kg (lb) Approximately 239 (527)
Fuel injection order 1 – 3 – 4 - 2
Fuel injection timing BTDC deg 8 -
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 JIS No. 2, DIN/EN590, GB252-1944 Diesel fuel
730  25 (A/C Off)
850  25 (A/C ON)
0.4 (0.016)
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)
25.527.0
(260275 / 3,7023,920) 2nd (Reference)
34.035.5
(347362 / 4,9365,154)
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)

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 liter
Compression ratio (to 1) 2,999
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)
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
2/psi)Hole with 5 orifices

1st 19.5 (199/2,828)
2nd (Reference) 34.335.8 (350365/4,9805,197)
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

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.

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 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)

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.

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.

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

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

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