Subaru IMPREZA 2002 Service Manual page 164

CYLINDER HEAD ASSEMBLY
MECHANICAL
3. VALVE GUIDE
1) Check the clearance between valve guide and
stem. The clearance can be checked by measuring
the outside diameter of valve stem and the inside
diameter of valve guide with outside and inside mi-
crometers respectively.
Clearance between the valve guide and valve
stem:
Standard
Intake 0.035
-
0.062 mm (0.0014
-
0.0024
in)
Exhaust 0.040
-
0.067 mm (0.0016
-
0.0026
in)
Limit
0.15 mm (0.0059 in)
Valve
1
guide
B2M0387A
I
1
%-
02M0076B
A
2) If the clearance between valve guide and stem
exceeds the limit, replace the valve guide or valve
itself whichever shows greater amount of wear.
See the following procedure for valve guide re-
placement:
Valve guide inner diameter:
Valve stem outer diameters:
6.000
-
6.012 mm (0.2362
-
0.2367 in)
Intake
5.950
-
5.965 mm (0.2343
-
0.2348 in)
Exhaust
5.945
-
5.960 mm (0.2341
-
0.2346 in)
(1) Place the cylinder head on STl with the
combustion chamber upward so that valve
guides enter the holes in STl.
(2) Insert ST2 into the valve guide and press it
down to remove the valve guide.
ST1 498267800 CYLINDER HEAD TABLE
ST2 499767200 VALVE GUIDE REMOVER
(STZ)
(3) Turn the cylinder head upside down and
place the ST as shown in the figure.
Intake side:
ST 499767700 VALVE GUIDE ADJUSTER
Exhaust side:
ST 499767800 VALVE GUIDE ADJUSTER
B2M0077D
(A) Valve guide
(4) Before installing a new oversize valve guide,
make sure that neither scratches nor damages
exist on the inside surface of the valve guide
holes in cylinder head.
ME(S0HC)-66