MAINTENANCE AND ADJUSTMENT 81
j
A. Thickness Gauge
Piston Ring/Rin
g Groove Clearance
KX85C 0.02 0.06 mm
(0.0008 0.0024 in.)
KX100F 0.04 0.08 mm
Standard
(0.0016 0.0031 in.)
KX85C 0.16 mm (0.0063 in.)
Service
Limit
KX100F
0.18 mm (0.0071 in.)
•
If
the piston ring/ring groove clearance is greater
than the service limit, measure the ring thickness
and groove width as fo
llows to decide whether to
replace the ring, the piston or both.
•
If the piston ring has worn down to less than the
service limit, replace the ring; if the piston ring
groove width exceeds the service lim it, replace the
piston.
Piston Ring Thickness Inspection
•
Measure the thickness at several points around
theringwithami
crometer.
Piston Ring Thickness
0.97 0.99 mm
Standard
(0.038 0.039 in.)
Service Limit 0.90 mm (0.035 in.)
•
If any of the measurements is less than the service
limit, replace the ring.
NO
TE
○
When using new ring in a used piston, check for
uneven groove wear. The ring should fit perfectly
parallel to the groove side. If not, replace the pis-
ton.
Piston Ring Groove Width Inspection
•
Measure the groove width at several points around
thepistonwithaverniercaliper.