Page 881 of 6020
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.
Tappet Outside Diameter mm (in)
Standard Limit
12.97 - 12.99
(0.510 - 0.511) 12.95 (0.510)
Tappet 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.
014RY00029
012LX014
014RY00031
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Page 882 of 6020

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)
014RY00032
014RY00033 014LX092
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Page 883 of 6020
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 (0.005)
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
014RY00034
014RY00035 014RY00036
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Page 884 of 6020

ENGINE MECHANICAL 6A – 79
CRANKSHAFT AND BEARING
Inspect the surface of the crankshaft journals and crankpins for
excessive wear and damage.
Inspect the oil seal fitting surfaces for excessive wear and
damage.
Inspect the oil ports for obstructions.
NOTE:
To increase crankshaft strength, tufftriding (Nitrizing
Treatment) has been applied. Because of this, it is not
possible to regrind the crankshaft surfaces.
Therefore, under size bearing are not available.
Crankshaft Run-Out
1. Set a dial indicator to the center of the crankshaft journal.
2. Gently turn the crankshaft in the normal direction of rotation.
Read the dial indicator as you turn the crankshaft.
If the measured value exceeds the specified limit, the
crankshaft must be replaced.
Crankshaft Run-Out mm (in)
Standard Limit
0.05 (0.002) or less 0.08 (0.003)
Bearing Spread
Use a vernier caliper to measure the bearing spread.
If the measured value is less than the specified limit, the
bearing must be replaced.
Bearing Spread mm
(in)
Limit
4JA1T (L), 4JA1TC 64.5 (2.54)
Creankshaft Bearing
4JH1TC 74.5 (2.93)
Connecting Rod Bearing 56.5 (2.22)
015LX061
015RY00007
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Page 885 of 6020

6A – 80 ENGINE MECHANICAL
Crankshaft Journal and Crankpin Diameter
1. Use a micrometer to measure the crankshaft journal
diameter across points 1 - 1 and 2 - 2.
2. Use the micrometer to measure the crankshaft journal diameter at the two points (3 and 4).
3. Repeat Steps 1 and 2 to measure the crankpin diameter. If the measured values are less than the specified limit, the
crankshaft must be replaced.
Crankshaft Journal and Diameter mm (in)
Standard Limit
4JA1T (L),
4JA1TC 59.921-59.928
(2.3591-2.3594) 59.91 (2.3586)
4JH1TC
69.917-69.932
(2.7526-2.7532) 69.91(2.7524)
Crankpin Diameter mm
(in)
Standard Limit
52.915 - 52.930
(2.0833 - 2.0839) 52.90 (2.083)
Crankshaft Journal and Crankpin Uneven W ear mm (in)
Standard Limit
0.05 (0.002) or less
0.08 (0.003)
Crankshaft Journal and Crankpin Diameter
If the clearance between the measured bearing inside diameter
and the crankshaft journal diameter exceeds the specified limit,
the bearing and/or the crankshaft must be replaced.
Crankshaft Journal and Bearing Clearance mm (in)
Standard Limit
0.032 - 0.077
(0.0013 - 0.0030) 0.110 (0.0043)
015RY00008
015RY00009
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Page 886 of 6020

ENGINE MECHANICAL 6A – 81
Connecting Rod Bearing Inside Diameter
1. Install the bearing to the connecting rod big end.
2. Tighten the bearing cap to the two step of anglar tightening 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 °
3. Use an inside dial indicator to measure the connecting rod
bearing inside diameter.
Crankpin and Bearing Clearance
If the clearance between the measured bearing inside diameter
and the crankpin exceeds the specified limit, the bearing
and/or the crankshaft 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
(0.0011-0.033) 0.100 (0.0039)
Clearance Measurements (With Plastigage)
Crankshaft Journal and Bearing Clearance
1. Clean the cylinder body, the journal bearing fitting surface, the bearing caps, and the bearings.
2. Install the bearings to the cylinder body.
3. Carefully place the crankshaft on the bearings.
4. Rotate the crankshaft approximately 30 ° to seat the
bearing.
5. Place the Plastigage (arrow) over the crankshaft journal across the full width of the bearing.
6. Install the bearing caps with the bearing.
7. Tighten the bearing caps to the specified torque.
Crankshaft Bearing Cap Bolt Torque mm (in)
167 (17/123)
Do not allow the crankshaft to turn during bearing cap
installation and tightening.
8. Remove the bearing cap.
015RY00012
015RY00013
015RY00011
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Page 887 of 6020

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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Page 888 of 6020

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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