4-1
ZHEJIANG KAYO MOTOR CO., LTD.
Specification
Item
Standard
Limitation
Cylinder
Inner diameter
62.450-62.550
62.650
Top parallelism
-
0.050
Deviations
-
0.050
Roundness
-
0.050
Piston
and
piston ring
Clearance
Top ring
0.025-0.060
0.090
Second ring
0.015-0.050
0.090
Clearance
of
piston
opening
Top ring
0.100-0.250
0.500
Second ring
0.250-0.400
0.650
Scraping ring
0.200-0.800
-
Outer diameter
62.450-62.500
62.410
Measure
position
of
outer
diameter
End 9mm
-
Piston and cylinder clearance
0.050-0.100
0.200
Inner diameter of piston pin hole
15.002-15.008
15.040
Piston pin outer diameter
14.994-15.000
14.960
Piston and piston pin clearance
0.002-0.014
0.020
Inner diameter of connected rod
15.016-15.034
15.060
Troubleshooting
Low or unstable compressive force: cylinder or piston ring worn.
High compressive force: piston or carbon deposit.
Knocking or abnormal sound: piston or cylinder worn; carbon deposit in piston head;
piston pin and pin hole worn.
Exhaust pipe with smoke: piston or piston ring worn; incorrect piston ring; cylinder or
piston worn.
Engine overheating: carbon deposit in piston head.
