Yamaha T135SE Service Manual page 139

VALVES AND VALVE SPRINGS
EASF0025
REMOVING THE VALVES
NOTE:
Prior to remove the valves, remove the cylinder
head, camshaft and rocker arms.
The following procedure applies to all of the
valves and related components.
NOTE:
Before removing the internal parts of the cylin-
der head (e.g., valves, valve springs, valve
seats), make sure the valves properly seal.
1. Check:
9 valve sealing
Leakage at the valve seat
valve face, valve seat, and valve seat width.
Refer to "CHECKING THE VALVE SEATS".
a. Pour a clean solvent a into the intake and
exhaust ports.
b. Check that the valves properly seal.
NOTE:
There should be no leakage at the valve seat
1 .
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