Isuzu NHR 4J Series, Workshop Manual

Page: 177 / 406

6A1 – 42 4JB1/4JB1T/4JB1TC/4JG2 - ENGINE
4JG2 Cylinder Head Gasket Thickness mm (in)
Gasket Grade Mark
Piston
Projection
Gasket Thickness
(Reference)
A
0.658 - 0.713
(0.026 - 0.028)
1.60
(0.0630)
B
0.713 - 0.759
(0.028 - 0.030)
1.65
(0.0650)
C
0.759 - 0.814
(0.030 - 0.032)
1.70
(0.0670)
NOTE:
The difference between the highest measured piston
head projection and the lowest measured piston head
projection must not exceed 1.0 mm (0.039 in).
19. Cylinder Head Assembly
1) Install the dowel in cylinder block.
2) Install the cylinder head gasket with top mark up.
3) Clean up cylinder head lower surface and cylinder
body upper surface.
4) Install the cylinder head as softly.
5) Apply engine oil to screw and seat of cylinder head
bolts.
6) Tighten the cylinder head bolts to the specified torque
in three steps following the numerical order shown in
the illustration.
Cylinder Head bolts Torque N ∙ m (kg ∙ m/lb ∙ ft)
1st Step 2nd Step 3rd Step
49 (5.0/36) 60 - 75° 60 - 75°
18. Push Rod
• Apply engine oil to push rod and in to the cylinder
head.
17. Rocker Arm shaft
1) Loosen all adjusting screws.
2) Position the rocker arm shaft with the large oil hole
(4ø) facing the front of the engine.
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