Subaru Legacy 2002 Service Manual page 1092

4) How to measure the outer diameter of each
piston
Measure the outer diameter of each piston at the
height shown in the figure. (Thrust direction)
CAUTION:
Measurement should be performed at a tem-
perature of 20°C (68°F).
Piston grade point H:
39.0 mm (1.535 in)
Piston outer diameter:
Standard
A: 89.185 — 89.195 mm
(3.5112 — 3.5116 in)
B: 89.175 — 89.185 mm
(3.5108 — 3.5112 in)
0.25 mm (0.0098 in) oversize
89.425 — 89.435 mm
(3.5207 — 3.5211 in)
0.50 mm (0.0197 in) oversize
89.675 — 89.685 mm
(3.5305 — 3.5309 in)
5) Calculate the clearance between cylinder and
piston.
CAUTION:
Measurement should be performed at a tem-
perature of 20°C (68°F).
Cylinder to piston clearance at 20°C (68°F):
Standard
0.010 — 0.030 mm (0.0004 — 0.0012 in)
Limit
0.050 mm (0.0020 in)
6) Boring and honing
(1) If the value of taper, out-of-roundness, or
cylinder-to-piston clearance measured exceeds
the specified limit or if there is any damage on
the cylinder wall, rebore it to use an oversize
piston.
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
boring on one cylinder only, nor use an over-
size piston for one cylinder only.
CYLINDER BLOCK
(2) If the cylinder inner diameter exceeds the
limit after boring and honing, replace the crank-
case.
CAUTION:
Immediately after reboring, the cylinder diam-
eter may differ from its real diameter due to
temperature rise. Thus, pay attention to this
when measuring the cylinder diameter.
Limit of cylinder enlarging (boring):
0.5 mm (0.020 in)
3. PISTON AND PISTON PIN
1) Check 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(H6)-69, CYLINDER
AND PISTON, INSPECTION, Cylinder Block.> If
any of the clearances is not to specification,
replace the piston or bore the cylinder to use an
oversize piston.
3) Make sure that piston pin can be inserted into
the piston pin hole with a thumb at 20°C (68°F).
Replace if defective.
Standard clearance between piston pin and
hole in piston:
Standard
0.004 — 0.008 mm (0.0002 — 0.0003 in)
Limit
0.020 mm (0.0008 in)
B2M1305A
ME(H6)-71
Mechanical
S143090A1004
B2M1401
B2M0084