Subaru Impreza 2003 Service Manual page 299

3) Make the sure that piston pin can be inserted
into 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)
4) Check the circlip installation groove on piston for
burr (A). If necessary, remove the burr from groove
so that piston pin can lightly move.
(A)
5) Check the piston pin circlip for distortion, cracks
and wear.
CYLINDER BLOCK
4. PISTON RING
1) If the piston ring is broken, damaged, or worn, or
if its tension is insufficient, or when the piston is re-
placed, replace the piston ring with a new one of
the same size as the piston.
CAUTION:
• Marks are shown on the end of top and sec-
ond rings. When installing the rings to piston,
face these marks upward.
• Oil ring is composed of upper rail, expander
and lower rail. Be careful of the rail direction
when installing oil ring to the piston.
ME-00173
ME-00174
2) Clean the piston ring groove and piston ring.
ME-00175
ME(H4SO)-87
(A) Upper rail
(B) Expander
(C) Lower rail
MECHANICAL
(A)
(B)
(C)
(A)
(B)
(C)
ME-00375