Yamaha TZ250M1, Owner'S Service Manual

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CYLINDER HEAD, CYLINDER AND PISTON
4-21
3. Remove:
• Piston ring
1
NOTE:
Take care not to scratch the piston and dam-
age the piston ring.
EC474000
INSPECTION
EC474110
Cylinder head
1. Remove:
• Carbon deposits
Use #400~600 grit wet sandpaper.
2. Inspect:
• Cylinder head water jacket
Crust of minerals/Rust
≥
Remove.
• Cylinder head contact surface
Wear/Damage
≥
Replace.
• Recess of insert portion
a
The contact surface
b
of the insert portion
is recessed below the aluminum portion
c
≥
Replace.
EC474210
Cylinder
1. Remove:
• Carbon deposits
Use a rounded scraper
1
.
NOTE:
Do not use a sharp instrument. Avoid scratch-
ing the aluminum.
2. Inspect:
• Cylinder inner surface
Score marks
≥
Repair or replace.
Use #400~600 grit wet sandpaper.
CC CAUTION:
Do not rebore the cylinder.
ENG