Subaru Legacy 2004 Service Manual page 308

MECHANICAL
Standard
2.0 L model
A: 92.005 — 92.015 mm (3.6222 — 3.6226
in)
B: 91.995 — 92.005 mm (3.6219 — 3.6222
in)
2.5 L model
A: 99.505 — 99.515 mm (3.9175 — 3.9179
in)
B: 99.495 — 99.505 mm (3.9171 — 3.9175
in)
0.25 mm (0.0098 in) oversize
2.0 L model
92.245 — 92.265 mm (3.6317 — 3.6325 in)
2.5 L model
99.745 — 99.765 mm (3.9270 — 3.9278 in)
0.50 mm (0.0197 in) oversize
2.0 L model
92.495 — 92.515 mm (3.6415 — 3.6423 in)
2.5 L model
99.995 — 100.015 mm (3.9368 — 3.9376 in)
5) Calculate the clearance between cylinder and
piston.
NOTE:
Measurement should be performed at a tempera-
ture of 20#C (68#F).
Cylinder to piston clearance at 20
Standard
$
0.010 — 0.010 mm (
6) Boring and honing
(1) If the value of taper, out-of-roundness, or
cylinder-to-piston clearance measured exceeds
the standard value or if there is any damage on
the cylinder wall, rebore it to use an oversize pis-
ton.
CAUTION:
When any of the cylinders needs reboring, all
other cylinders must be bored at the same time,
and use oversize pistons. Do not perform bor-
ing on one cylinder only. Nor use an oversize
piston for one cylinder only.
Cylinder Block
H
ME-00172
# #
C (68 F):
$
0.00039 — 0.00039 in)
ME(H4SO 2.0)-78
(2) If the cylinder inner diameter exceeds limit*
after boring and honing, replace the cylinder
block.
*: 2.0 L model
92.515 mm (3.6423 in)
2.5 L model
100.015 mm (3.9376 in)
NOTE:
Immediately after reboring, the cylinder diameter
may differ from its real diameter due to temperature
rise. Thus, pay attention when measuring the cylin-
der diameter.
Limit of cylinder boring:
0.5 mm (0.020 in)
3. PISTON AND PISTON PIN
1) Check the pistons and piston pins for damage,
cracks and wear, and the piston ring grooves for
wear and damage. Replace if defective.
2) Measure the piston-to-cylinder clearance at
each cylinder. <Ref. to ME(H4SO 2.0)-76, CYLIN-
DER AND PISTON, INSPECTION, Cylinder
Block.> If any of the clearances is not within the
standard value, replace the piston. Or bore the cyl-
inder to use an oversize piston.
3) Make sure that the piston pin can be inserted
into the piston pin hole with a thumb at 20#C (68#F).
Replace if defective.
Clearance between piston hole and piston pin:
Standard
0.004 — 0.008 mm (0.0002 — 0.0003 in)
ME-00173
ME-00174