7.9.3 To clean the cylinder and piston
CAUTION: Clean carefully. The soft aluminum
parts are easily damaged.
•
Remove the carbon deposits from these parts:
a) The top of the piston.
b) The combustion chamber of the cylinder.
c) The exhaust port of the cylinder.
•
Use a screwdriver to remove dirt particles from the
cooling fins.
•
Clean all parts.
•
Clean the piston ring groove.
7.9.4 To examine the cylinder
•
Make sure that the surface layer of the cylinder is
not worn, especially in the top end of the cylinder.
•
Make sure that the cylinder does not have score
marks.
7.9.5 To examine the piston
•
Make sure that the piston ring can move freely in the
groove.
•
Examine the surface of the piston for damage and
wear.
•
Examine the piston pin. Refer to
piston pin on page 32.
•
Examine the snap rings. If the snap rings have
cracks or discoloration, replace them.
•
Measure the piston ring groove (A). Replace the
piston if the groove is larger than 1.6 mm.
A
B
•
Measure the piston ring play (B). Replace the piston
ring if the piston ring play is larger than 0.15 mm.
1281 - 001 -
Repair instructions - 31
Summary of Contents for 331RB
Page 1: ...Workshop manual 331RB English 1281 001 ...
Page 47: ...1281 001 Technical data 47 ...
Page 48: ...1141483 26 2019 09 27 ...
