Isuzu 4ja1, Workshop Manual

Page: 104 / 564

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