KYMCO ZX/SCOUT 50, Service Manual

Page: 66 / 191

6
. CYLINDER HEAD/CYLINDER/PISTON
6-9
ZX / SCOUT
PISTON RING INSPECTION
Measure each piston ring end gap.
Service Limits : Top/Second
0.40mm replace if over
CONNECTING ROD SMALL END
INSPECTION
Install the piston pin and bearing in the
connecting rod small end and check for
excessive play.
Measure the connecting road small end I.D.
Service Limit :
17.03mm replace if over
PISTON/CYLINDER INSTALLATION
First install the expander in the second ring
groove.
Then install the top and second rings in
their respective ring grooves.
The piston rings should be pressed into the
grooves with even force.
After installation, check and make sure that
each ring is flush with the piston at several
points around the ring.
A ring that will not compress means that
the ring groove has carbon deposits in it
and should be cleaned.
Set each piston ring squarely into the
cylinder using the piston and measure
the end gap.
<Small End I.D. Measurement>
piston
Top ring
Sencond ring
expander