Suzuki MT50 Service & Parts Manual page 134

B. . Checking wear and damage:
Inspect the piston pin holes and piston ring
locating pins for wear and the piston surface
for burned spots, scratches, etc.
worn locating pins allow piston rings to turn
in the grooves and possibly catch on the ports
of 1the cylinder.
spots or scratches on its surface, cylinder noise
is produced and engine rotation becomes un­
smooth, resulting in loss of engine power.
Further, the piston is apt to seize at these
points. Replace if badly worn, and repair
burns or minor defects with
9-9-2. Servicing
Remove carbon deposits
crown and ring grooves with a knife or broken
piece of an old piston ring.
on the crown increase compression and cause
engine overheating, and those in the piston
ring grooves make the movement of the piston
rings unsmooth resulting in compression leak­
age.
9-9-3. Installing
As the piston pin ·holes are off-center, the
piston can be installed only in one direction.
If it is installed backwards, the scavenging
ports will not align with the slots on the
piston skirt, which affects engine performance
badly. Be sure to install the piston with the
arrow mark pointing toward the exhaust port.
32
Excessively
If the piston has burned
l+400 emery paper.
from the piston
Carbon deposits
Fig. 9-9-3. Polishing piston surface
Fig. 9-9-4 Piston ring locating pins
Fig. 9-9-5 Removing carbon from ring
grooves
Fig. 9-9-6 Arrow mark
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