Isuzu NHR 4J Series, Workshop Manual

Page: 134 / 406

GENERAL ENGINE MECHANICAL 6A – 67
4JG2 Cylinder Head Gasket Thickness mm (in)
Grade
mark
Average Piston
projection
Gasket
thickness
A
0. 658-0.713
(0.0259-0.0281)
1.60
(0.0630)
B
0.713-0.759
(0.0281-0.0299)
1.65
(0.0650)
C
0.759-0.814
(0.0299-0.0320)
1.70
(0.0670)
NOTE:
The difference between the highest measured piston
head projection and the lowest measured piston head
projection must not exceed 1.0mm (0.039 in).
Cylinder Head Assembly
!
Install the dowel in cylinder block.
"
Install the cylinder head gasket with top mark up.
#
Clean up cylinder head lower surface and cylinder
body upper surface.
$
Install the cylinder head as softly.
%
Apply molybdenum disulfide grease to screw and seat
of cylinder head bolts.
&
Tighten the cylinder head bolts to the specific torque in
three step following the numerical and 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°
Push Rod
• Apply engine oil to push rod and into the cylinder head.
Rocker Arm Shaft Assembly
!
Loosen all adjusting screws.
"
Position the rocker arm shaft with the large oil hole
(4ø) facing the front of the engine.
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