Inspecting Piston And Piston Ring - Echo shindaiwa CSG-7410ES Service Manual

CSG-7410ES
EC741S
7-7 Inspecting piston and piston ring
A
B
F
G
ENGINE
1. Inspect piston ring (A) and (B). If broken or
scored, or if it exceeds service limits (Refer to "1-5"),
replace with new one(s) (Refer to "7-10 I n s t a l l i n g
piston and cylinder").
2. When removing piston rings, remove top ring (A)
at first and then remove second ring (B).
3. Inspect piston crown, top land, ring groove and
skirt. If carbon is found, remove piston and then
clean it as follows.
4. Insert awl (F) or suitable pointed tool into con-
cave area (G) of piston pin hole and remove snap
ring (H) from both sides of piston pin.
NOTE: Piston holder 897719-02830 (C) is recom-
mended.
NOTE: Do not reuse removed snap rings. Make
H
sure to replace with new ones.
C
5. Push piston pin out from piston.
NOTE: If piston pin is tight, use Piston pin tool
X640-000090 with adapter (J) stamped "757".
J
6. Inspect needle bearing (L) and piston pin (K),
and replace if wear or discoloration is noted (Refer
to "7-10 Installing piston and cylinder").
7. Clean piston crown with fine sand paper, oil
stone, or soft cleaning brush (D).
8. Clean piston top land, ring groove and skirt with
soft cleaning brush (D).
NOTE: Do not use square end of broken piston
ring when cleaning piston ring groove, otherwise
piston ring groove might be damaged.
51
L
K