JAC J2 User Manual

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Maintenance Manual for J2 Sedan
Mechanical Part of Engine
72
Standard values:
For intake valve: 53.21mm
For exhaust valve: 54.10mm
Limits:
For intake valve: 53.71mm
For exhaust valve: 54.60mm
■
Renew
valve
seat.
a.
Before renewing the
valve seat,
check
the
clearance be
tween valve
guide and
valve. Replace
the
valve guide if necessary.
b.
Resurfacin
g
the valve
seat
by the
proper special
tool or
the valve
seat grinder
till specified
seat
surface width and angle are met.
c.
After renewin
g the va
lve seat,
grind the
valve and
the valve seat by the grinding cream. Then,
check the protrusion height of valve stem (refer to the above mentioned check steps of valve seat)
■
Replacement
of
V
alve
Seat
a. Cut
away
the
replaced
valve seat
from
its
inner side in order to decrease the wall
thickness. Then remove the valve seat.
b.
Rebore
the
valve
seat
hole
on
cylinder
head
till the hole matches the selected valve seat
with a extended diameter. See “Parameters
for Maintenance” for the detailed size.
c.
Do
not
have
the
cylinder
head
hole
scratched
by the valve seat cooled by the liquid
nitrogen before it is
pressed.
d.
Renew
the
valve
seat
till
its
width
and
angle
meet the specifications (see the operation
instruction of valve seat correction).
e. leak testing must be conducted for
disassembly of valve
related componen
ts.
XIII.
Cylinder
Body
Assembly
图
图图
图
1.1.052
Fig.1.1.053
Fig.1.1.054
End Face of
Valve Stem
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Valve Protrusion
Height
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Surface of Valve
Spring Seat
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Cut Away
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Valve Seat
Height
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Inner Diameter of Extended Hole
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JAC J2 Specifications

General

Brand	JAC
Model	J2
Category	Automobile
Language	English