Subaru IMPREZA 2002 Service Manual page 163

CYLINDER HEAD ASSEMBLY
MECHAN ICP
I
F: ADJUSTMENT
1. CYLINDER HEAD
1) Make sure that no crack or other damage do not
exists. In addition to visual inspection, inspect im-
portant areas by means of red lead check.
Also make sure the gasket installing surface shows
no trace of gas and water leaks.
2) Place the cylinder head on ST.
ST 498267800 CYLINDER HEAD TABLE
3) Measure the warping of the cylinder head sur-
face that mates with crankcase using a straight
edge (A) and thickness gauge (B).
If the warping exceeds 0.05 mm (0.0020 in), re-
grind the surface with a surface grinder.
Warping limit:
Grinding limit:
Standardheight of cylinder head:
CAUTION:
Uneven torque for the cylinder head bolts can
cause warping. When reassembling, pay spe-
cial attention to the torque so as to tighten
evenly.
0.05 mm (0.0020 in)
0.1 mm (0.004 in)
97.5 mm (3.839 in)
( B )
S2M1817A
2. VALVESEAT
Inspect the intake and exhaust valve seats, and
correct the contact surfaces with a valve seat cutter
if they are defective or when valve guides are re-
placed.
Valve seat width: W
Intake
Limit 1.7 mm (0.067 in)
Exhaust
Limit 2.1 mm (0.083 in)
Standard 1.0 mm (0.039 in)
Standard 1.4 mm (0.055 in)
G2M0149
ME(S0HC)-65