Mitsubishi S4Q2 User Manual

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Service Manual Mitsubishi SQ-Series diesel engines
Version 08/2004
CYLINDER HEADS AND VALVE
MECHANISM
ENGLISH
ENGINE MAIN PARTS
7.2.1 Cylinder head
Using a heavy accurate straight edge and a feeler
gage, check for warpage in three positions lengthwise,
two crosswise and two widthwise, as shown in the
illustration. If warpage exceeds the repair limit, reface
the head with a surface grinder.
Unit: mm [in.]
7.2.2 Rocker arms and rocker shafts
1. Measuring rocker arm bushing and rocker shaft
Measure the inside diameter of the rocker arm
(bushing bore) and the diameter of the rocker
shaft, as shown in the illustration, to check the
clearance between the rocker arm and shaft. If the
clearance is not correct, within the repair limit,
replace the rocker arm. If it exceeds the repair
limit, replace both rocker arm and bushing.
Unit: mm [in.]
Figure 17 Checking cylinder head for warpage
Item
Assembly
Standard
Repair Limit
Warpage of
bottom face
0.05
[0.0020] or less
0.20
[0.0079]
Figure 18 Measuring rocker arm bushing and rocker
shaft
Item
Nominal
Value
Assembly
Standard
Repair
Limit
Inside diameter
of rocker arm
bushing
19
[0.75]
19.010 to
19.030
[0.7484 to
0.7492]
__
Diameter of
rocker shaft
19
[0.75]
18.980 to
19.000
[0.7472 to
0.7480]
__
Clearance
between rocker
bushing and
shaft
__
0.010 to
0.050
[0.0004 to
0.0020]
0.070
[0.0028]

Mitsubishi S4Q2 Specifications

General

Brand	Mitsubishi
Model	S4Q2
Category	Engine
Language	English