4JH1 ISUZU KB P190 2007 Workshop Workshop Manual

6A – 82 ENGINE MECHANICAL




































9. Compare the width of the Plastigage attached to either the
crankshaft or the bearing against the scale printed on the
Plastigage container.
If the measured value exceeds the limit, perform the
following additional steps.
1. Use a micrometer to measure the crankshaft outside diameter.
2. Use an inside dial indicator to measure the bearing inside diameter.
If the crankshaft journal and bearing clearance
exceeds the limit, the crankshaft and/or the bearing
must be replaced.

Crankshaft Journal and Bearing Clearance mm (in)
Standard Limit
0.032 - 0.077
(0.0013 - 0.0030) 0.110 (0.0043)
































Crankpin and Bearing Clearance
1. Clean the crankshaft, the connecting rod, the bearing cap, and the bearings.
2. Install the bearing to the connecting rod and the bearing cap.
Do not allow the crankshaft to move when installing the
bearing cap.
3. Prevent the connecting rod from moving.
4. Attach the Plastigage to the crankpin. Apply engine oil to the Plastigage to keep it from falling.
5. Install the bearing cap and tighten it to the two step of anglar tihtening method.
Do not allow the connecting rod to move when installing
and tightening the bearing cap.

Connecting Rod Bearing Cap Bolt Torque
N·m (kg·m/Ib ft)
4JA1T (L), 4JA1TC 78-88 (8.0/57 – 9.0/65)
1st step ; 29.0–29.2 (3.00/22.0–3.01/22.2)4JH1TC
2nd step ; 45°-60 °
015LX129
015LX060

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ENGINE MECHANICAL 6A – 83































6. Remove the bearing cap.
7. Compare the width of the Plastigage attached to either the crankshaft or the bearing against the scale printed on the
Plastigage container.
If the measured value exceeds the specified limit, perform
the following additional steps.
1. Use a micrometer to measure the crankpin outside diameter.
2. Use an inside dial indicator to measure the bearing inside diameter.
If the crank pin and bearing clearance exceeds the
specified limit, the crankshaft and/or the bearing must
be replaced.

Crankpin and Bearing Clearance mm (in)
Standard Limit
4JA1T (L),
4JA1TC 0.029-0.066
(0.0011-0.0026) 0.100 (0.0039)
4JH1TC
0.029-0.083
(0.0011-0.0033) 0.100 (0.0039)

CRANKSHAFT BEARING SELECTION
Crankshaft bearing selection is based on the measured
diameters of the crankshaft journals and the bearing inserts.
Match the crankshaft bearing housing grade marks and the
crankshaft journal grade marks in the table below to determine
the correct crankshaft bearing size.

Crankshaft Bearing Housing Grade Mark
Position
Crankshaft bearing housing grade marks 1, 2 or 3 are stamped
on the rear right hand side of the cylinder body.




Crankshaft Journal Grade Mark Position
The crankshaft journal grade marks (1 or -, 2 or --, 3 or ---) are
stamped on each crankshaft journal web.
The crankshaft journal and bearing clearance must be the
same for each position after installation of the crankshaft and
the crankshaft bearings.

NOTE:
The crankshaft journal mark No. 4 is stamped on
crankshaft No. 4 journal web front side or rear side.
015LX060
015RY00016

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6A – 84 ENGINE MECHANICAL


015RY00017



RTW46ASH002501
REFERENCE

4JA1T(L), 4JA1TC mm (in)
Crankshaft
Bearing Housing Crankshaft Journal
Grade
Mark Diamaeter
Grade
Mark Diamaeter Crankshaft
Bearing
Size Code
1 or - 59.927-59.932
(2.3593-23.595)
2 or - - 59.922-59.927
(2.3591-2.3539) Brown or 41
63.992-
64.000
(2.5194-
2.5197) 3 or
- - - 59.917-59.922
(2.3589-2.3591) Yellow or 5
1 or
- 59.927-59.932
(2.3593-2.3595) Black or 2
2 or
- - 59.922-59.927
(2.3591-2.3593) Blue or 3 2 63.983-
63.992
(2.5190-
2.5194) 3 or
- - - 59.917-59.922
(2.3589-2.3591) Brown or 4
1 or
- 59.927-59.932
(2.3593-2.3595) Green or 1
2 or
- - 59.922-59.927
(2.3591-2.3593)3 63.975-
63.983
(2.5187-
2.5190) 3 or
- - - 59.917-59.922
(2.3598-2.3591) Black or 2

4JH1TC mm (in)
Crankshaft
Bearing Housing Crankshaft Journal
Grade
Mark Diamaeter
Grade
Mark Diamaeter Crankshaft
Bearing
Size Code
1 or - 69.927-69.932
(2.7530-2.7532)
2 or - - 69.922-69.927
(2.7528-2.7530) 4 1
73.992-
74.000
(2.9131-
2.9134) 3 or
- - - 69.917-69.922
(2.7556-2.7528) 5
1 or
- 69.927-69.932
(2.7530-2.7532) 2
2 or
- - 69.922-69.927
(2.7528-2.7530) 3 2 73.983-
73.992
(2.9127-
2.9131) 3 or
- - - 69.917-69.922
(2.7556-2.7528) 4
1 or
- 69.927-69.932
(2.7530-2.7532) 1
2 or
- - 69.922-69.927
(2.7528-2.7530)3 73.975-
73.983
(2.9124-
2.9127) 3 or
- - - 69.917-69.922
(2.7526-2.7528) 2

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ENGINE MECHANICAL 6A – 85
CRANKSHAFT PILOT BEARING
Check the crankshaft pilot bearing for excessive wear and
damage and replace it if necessary.















Crankshaft Pilot Bearing Replacement
Crankshaft Pilot Bearing Removal
Use the pilot bearing remover to remove the crankshaft pilot
bearing.
Pilot Bearing Remover: 5-8840-2000-0
Sliding Hammer: 5-8840-0019-0
















Crankshaft Pilot Bearing Installation
1. Place the crankshaft pilot bearing right angle across the crankshaft bearing installation hole.
2. Tap around the edges of the crankshaft pilot bearing outer races with a brass hammer to drive the bearing into the
crankshaft bearing installation hole.
Pilot Bearing Installer: 5-8522-0024-0

NOTE:
Strike only the crankshaft pilot bearing outer race with
the hammer. Do not strike the bearing inner race.
Bearing damage and reduced bearing service life will
result.







































FLYWHEEL AND RING GEAR
Flywheel
1. Inspect the flywheel friction surface for excessive wear and
heat cracks.
2. Measure the flywheel friction surface depth. If the measured value is within the specified limit, the
flywheel may be reground.
If the measured value exceeds the specified limit, the
flywheel must be replaced.

Flywheel Friction Surface Depth (1) mm (in)
Standard Limit
4JA1T (L),
4JA1TC 20 (0.7874) 21 (0.8267)
4JH1TC 18 (0.7087) 19 (0.7480)

Ring Gear
Inspect the ring gear.
If the ring gear teeth are broken or excessively worn, the ring
gear must be replaced.
015RY00010
015RY00019 015RY00018

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ENGINE MECHANICAL 6A – 87

3. Use a feeler gauge to measure the piston ring gap. If the measured value exceeds the specified limit, the
piston ring must be replaced.

Piston Ring Gap mm (in)
4JA1T (L), 4JA1TC
Standard Limit
1st Compression Ring
2nd Compression Ring 0.3-0.3
(0.0118-0.0197)
Oil Ring 0.250-0.450
(0.0098-0.0177) 1.5
(0.059)


4JH1TC
Standard Limit
1st Compression Ring
2nd Compression Ring 0.3-0.5
(0.0118-0.0197)
Oil Ring 0.250-0.450
(0.0098-0.0177) 1.5
(0.059)


Piston Ring and Piston Ring Groove Clearance
Use a feeler gauge to measure the clearance between the
piston ring and the piston ring groove at several points around
the piston.
If the clearance between the piston ring and the piston ring
groove exceeds the specified limit, the piston ring must be
replaced.

Piston Ring and Piston Ring Groove Clearance mm (in)
4JA1T (L), 4JA1TC
Standard Limit
1st Compression Ring 0.09-0.125
(0.0035-0.0049)
2nd Compression Ring 0.05-0.085
(0.0020-0.0033)
Oil Ring 0.03-0.070
(0.0012-0.0028) 0.15
(0.0059)


4JH1TC
Standard Limit
1st Compression Ring 0.09-0.130
(0.0035-0.0051)
2nd Compression Ring 0.05-0.090
(0.0020-0.0035)
Oil Ring 0.03-0.070
(0.0012-0.0028) 0.15
(0.0059)

015RY00021
015LX025

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6A – 88 ENGINE MECHANICAL


4. Visually inspect the piston rings.
If a piston ring groove is damaged or distorted, the piston
must be replaced.



Piston Pin Diameter
Use a micrometer to measure the piston pin diameter at
several points.
If the measured value is less than the specified limit, the piston
pin must be replaced.

Piston Pin Diameter mm
(in)
Standard Limit
30.995-31.000
(1.2202-1.2204) 30.97
(1.2193)


Piston Pin and Piston Clearance
Use and inside dial indicator to measure the piston pin hole (in
the piston).

Piston Pin Hole mm
(in)
4JA1T (L) 31.002-31.010 (1.2206-1.2208)
4JA1TC, 4JH1TC 31.005-31.013 (1.2207-1.2210)

Piston Pin and Piston Pin Hole Clearance mm (in)
4JA1T (L) 0.002-0.015 (0.00008-0.0006)
4JA1TC, 4JH1TC 0.005-0.018 (0.0002-0.0007)



















CYLINDER HEAD GASKET SELECTION
Cylinder head gasket is determined by the piston head
projection from the cylinder body upper surface, in order to
improve engine performance.
Three types of gasket are provided by the difference of
thickness. Select the adequet one out of three grades of
gasket, according to the following procedure.
Before measurement, clear off carbon from the piston head
and cylinder body surface and also clean the place where a
gasket was installed.
015LX026
015RW048
011LX011

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ENGINE MECHANICAL 6A – 89


RTW36ASH001701
Piston Head Projection Measuring Point
1. Use a dial indicator to measure the piston projection
amount.
2. Refer to the illustration for the piston head projection measuring positions.
All measuring positions should be as close as possible to
the cylinder liner.



3. Measure the points 1, 2, 3, 4 and obtain two differences 1- 2 and 3-4 on each cylinder.
Calculate the average value of the piston head projection
on each cylinder.
4. Obtain the maximum value in the four cylinders.
5. Determine the gasket grade required to the maximum value described above in accordance with the following
table.

Cylinder Head Gasket Combination mm (in)

Cylinder Head Gasket Combination
4JA1T (L), 4JA1TC mm (in)
Gasket Grade Mark Piston Projection Gasket Thickness
(Reference)
A 0.718-0.773
(0.0283-0.0304) 1.6
(0.0630)
B 0.773-0.819
(0.0304-0.0322) 1.65
(0.0650)
C 0.819-0.874
(0.0322-0.0344) 1.70
(0.0669)


4JH1TC mm (in)
Gasket Grade Mark Piston Projection Gasket Thickness
(Reference)
A 0.215-0.265
(0.0085-0.0104) 1.3
(0.5118)
B 0.265-0.315
(0.0104-0.0124) 1.35
(0.5315)
C 0.315-0.365
(0.0124-0.0144) 1.4
(0.5512)
NOTE:
Difference of the each piston projection and must be
equal or within 0.1 mm (0.004 in).


011RY00027
011RY00030

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6A – 90 ENGINE MECHANICAL






CONNECTING ROD
Connecting Rod Alignment
Use a connecting rod aligner to measure the distortion and the
parallelism between the connecting rod big end hole and the
connecting rod small end hole.
If either the measured distortion or parallelism exceed the
specified limit, the connecting rod must be replaced.

Connecting Rod Alignment Per Length of 100 mm (3.94 in)
mm (in)
Standard Limit
Distortion 0.08 (0.003) or Less 0.20 (0.008)
Parallelism 0.05 (0.002) or Less 0.15 (0.006)


Connecting Rod Side Face Clearance
1. Install the connecting rod to the crankpin.
2. Use a feeler gauge to measure the clearance between the connecting rod big end side face and the crankpin side
face.
If the measured value exceeds the specified limit, the
connecting rod must be replaced.


Connecting Rod Big End and Crankpin Side Face Clearance
mm (in)
Standard Limit
0.23 (0.009) 0.35 (0.014)


Piston Pin and Connecting Rod Small End
Bushing Clearance
Use a caliper calibrator and a dial indicator to measure the
piston pin and connecting rod small end bushing clearance.
If the clearance between the piston pin and the connecting rod
small end bushing exceeds the specified limit, replace the
piston pin and/or the connecting rod.

Piston Pin and Connecting Rod Small End
Bushing Clearance mm (in)
Standard Limit
4JA1T (L) 0.008-0.020
(0.003-0.0008) 0.050 (0.002)
4JA1TC,
4JH1TC 0.005-0.018
(0.0002-0.0007) 0.050 (0.002)

015LX034
011RY00029 015LX028

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6A – 108 ENGINE MECHANICAL











10. Apply a coat of engine oil to the threads and setting
faces of each connecting rod cap bolt.
11. Tighten the connecting rod caps to the two step of anglar tigthen method.

Connecting Rod Bearing Cap Bolt Torque N·m (kg·m/Ib ft) 4JA1T (L), 4JA1TC 78-88 (8.0/57 – 9.0/65)
1st step; 29.0–29.2 (3.00/22.0–3.01/22.2) 4JH1TC
2nd step; 45°-60 °






13. Piston Cooling Oil Jet
1. Install the piston cooling oil jet to the cylinder body.
2. Tighten the oil jet bolts and relief valve to the specified torque.

Oil Jet Bolt Torque N·m(kg·m/lb ft)
M8 × 1.25 19 (1.9/14)
M6
× 1.00 8 (0.8/6)


Relief Valve Torque N·m(kg·m/lb ft)
29 (3.0/22)
NOTE:
Check that there is no interference between the piston
and the oiling jet by slowly rotating the crankshaft.
















14. Oil Pump with Oil Pipe Apply a coat of the molybdenum disul fide and engine oil
enough on the pinion gear.
Install the oil pump with the oil pipe and tighten the bolts to
the specified torque.

Oil Pump Bolt Torque N·m(kg·m/lb ft)
19 (19/14)
NOTE:
Take care not to damage the O-rings when tightening
the oil pipe bolts.







15. Crankshaft Rear Oil Seal
Use a oil seal install to install the crankshaft rear oil seal.
Oil Seal Installer: 5-8840-2359-0


015LX130
015LX112
052LX010
051R100004

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6A – 114 ENGINE MECHANICAL








23. Injection Pump
1. Install the O-ring (1) to the injection pump flange (2).
2. Attach the noise insulator rubber to the cylinder body .
3. Install the injection pump to the timing gear case.Align the idler gear "B" (3) mark with the injection pump timing
gear (4) mark.












RTW 36AMH000101


























4JA1TC/4JH1TC:
4. Tighten the injection pump bolts (5) to the specified torque.

Injection Pump Bolt Torque N·m(kg·m/lbft)
19 (1.9/14)

5. Install the injection pump bracket (6) and the bracket bolts (7) and (8) to the cylinder body.
Temporarily tighten the bracket bolts.
6. Tighten the bracket bolts (7) to the specified torque.
7. Tighten the bracket bolt (8) to the specified torque.
NOTE:
Tighten the bracket bolt (7) first.

Injection Pump Bracket Bolt Torque N·m(kg·m/lbft)
19 (1.9/14)




020RY00039

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