Subaru Legacy 2002 Service Manual page 377

Mechanical
2. CYLINDER AND PISTON
1) The cylinder bore size is stamped on the cylin-
der block's front upper surface.
CAUTION:
Measurement should be performed at a tem-
perature 20°C (68°F).
NOTE:
Standard sized pistons are classified into two
grades, "A" and "B". These grades should be used
as a guide line in selecting a standard piston.
Standard diameter:
2000 cc model
A: 92.005 — 92.015 mm (3.6222 — 3.6226
in)
B: 91.995 — 92.005 mm (3.6218 — 3.6222
in)
2500 cc model
A: 99.505 — 99.515 mm (3.9175 — 3.9179
in)
B: 99.495 — 99.505 mm (3.9171 — 3.9175
in)
(A) Main journal size mark
(B) Cylinder block RH-LH combination mark
(C) #1 cylinder bore size mark
(D) #2 cylinder bore size mark
(E) #3 cylinder bore size mark
(F) #4 cylinder bore size mark
CYLINDER BLOCK
S173090A1002
H2M1732C
ME-88
2) How to measure the inner diameter of each
cylinder
Measure the inner diameter of each cylinder in
both the thrust and piston pin directions at the
heights shown in the figure, using a cylinder bore
gauge.
CAUTION:
Measurement should be performed at a tem-
perature 20°C (68°F).
Taper:
Standard
0.015 mm (0.0006 in)
Limit
0.050 mm (0.0020 in)
Out-of-roundness:
Standard
0.010 mm (0.0004 in)
Limit
0.050 mm (0.0020 in)
(A) Piston pin direction
(B) Thrust direction
3) When piston is to be replaced due to general or
cylinder wear, determine a suitable sized piston by
measuring the piston clearance.
S2M1821A