Subaru 2004 Impreza Service Manual page 6

MECHANICAL
Surface warpage limit (mating with cylinder head)
Surface grinding limit
Standard height
Cylinder bore
Cylinder
block
Taper
Out-of-roundness
Piston clearance
Enlarging (boring) limit
Outer diameter
Piston
Standard inner diameter of piston pin hole
Outer diameter
Standard clearance between piston pin and hole in pis-
Piston pin ton
Degree of fit
Piston ring gap
Piston ring
Clearance
between piston
ring and piston
ring groove
General Description
A
1.6 L STD
B
A
2.0 L STD
B
A
2.5 L STD
B
STD
Limit
STD
Limit
STD
Limit
A
STD
B
0.25 mm (0.0098 in)
1.6 L
OS
0.50 mm (0.0197 in)
OS
A
STD
B
0.25 mm (0.0098 in)
2.0 L
OS
0.50 mm (0.0197 in)
OS
A
STD
B
0.25 mm (0.0098 in)
2.5 L
OS
0.50 mm (0.0197 in)
OS
STD
Top ring
Limit
1.6 L,
2.5 L
STD
Second
ring 2.0 L
Limit
STD
Oil ring
Limit
STD
Top ring
Limit
STD
Second
ring
Limit
ME(H4SO)-4
0.05 mm (0.0020 in)
0.1 mm (0.004 in)
201.0 mm (7.91 in)
87.905 — 87.915 mm (3.4608 — 3.4612 in)
87.895 — 87.905 mm (3.4604 — 3.4608 in)
92.005 — 92.015 mm (3.6222 — 3.6226 in)
91.995 — 92.005 mm (3.6218 — 3.6222 in)
99.505 — 99.515 mm (3.9175 — 3.9179 in)
99.495 — 99.505 mm (3.9171 — 3.9175 in)
0.015 mm (0.0006 in)
0.050 mm (0.0020 in)
0.010 mm (0.0004 in)
0.050 mm (0.0020 in)
0.010 — 0.030 mm (0.0004 — 0.0012 in)
0.050 mm (0.0020 in)
0.5 mm (0.020 in)
87.885 — 87.895 mm (3.4600 — 3.4604 in)
87.875 — 87.885 mm (3.4596 — 3.4600 in)
88.125 — 88.135 mm (3.4695 — 3.4699 in)
88.375 — 88.385 mm (3.4793 — 3.4797 in)
91.985 — 91.995 mm (3.6214 — 3.6218 in)
91.975 — 91.985 mm (3.6211 — 3.6214 in)
92.225 — 92.235 mm (3.6309 — 3.6313 in)
92.475 — 92.485 mm (3.6407 — 3.6411 in)
99.485 — 99.495 mm (3.9167 — 3.9171 in)
99.475 — 99.485 mm (3.9163 — 3.9167 in)
99.725 — 99.735 mm (3.9262 — 3.9266 in)
99.975 — 99.985 mm (3.9360 — 3.9364 in)
23.000 — 23.006 mm (0.9055 — 0.9057 in)
22.994 — 23.000 mm (0.9053 — 0.9055 in)
0.004 — 0.008 mm (0.0002 — 0.0003 in)
Piston pin must be fitted into position with thumb at 20°C
(68°F).
0.20 — 0.35 mm (0.0079 — 0.0138 in)
1.0 mm (0.039 in)
0.35 — 0.50 mm (0.0138 — 0.0197 in)
0.40 — 0.50 mm (0.0157 — 0.0197 in)
1.0 mm (0.039 in)
0.20 — 0.50 mm (0.0079 — 0.0197 in)
1.5 mm (0.059 in)
0.040 — 0.080 mm (0.0016 — 0.0031 in)
0.15 mm (0.0059 in)
0.030 — 0.070 mm (0.0012 — 0.0028 in)
0.15 mm (0.0059 in)