Checking The Pisotn Rings - Yamaha EK25BMH Service Manual

POWR
CRANKSHAFT AND CYLINDER BODY
4. Check:
• Free play (when piston pin is in
place of the piston).
There should be no noticeable play.
Free play exists → Replace the pin
and/or piston.

CHECKING THE PISOTN RINGS

NOTE:
• Before checking the piston rings, be
sure to check the cylinder body.
• Piston rings should be replaced as a set
(per piston).
1. Check:
• Piston ring
Broken/damage → Replace.
2. Measure:
• Piston ring end gap
(use a thickness gauge)
Out of specification → Replace.
Piston ring end gap
0.20 - 0.35 mm (0.0079 - 0.0137 in)
Piston ring end gap limit
0.35 mm (0.014 in)
Measuring point "H"
15 mm (0.591 in)
5-33
E
a