Suzuki GSF600Y 2000 Service Manual page 97

ENGINE 3-59
VALVE SEAT SEALING CONDITION INSPECTION
Clean and assemble the cylinder head and valve components.
Fill the intake and exhaust ports with gasoline to check for leaks.
If any leaks occur, inspect the valve seat and face for burrs or
other things that could prevent the valve from sealing.
'
Always use extreme caution when handling gasoline.
NOTE:
After servicing the valve seats, be sure to check the valve clear-
ance after the cylinder head has been reinstalled. ( $ 2-4)
VALVE STEM END CONDITION
Inspect the valve stem end face for pitting and wear. If pitting or
wear is present, resurface the valve stem end. Make sure that the
length 1 is not less than 2.5 mm (0.10 in). If this length becomes
less than 2.5 mm (0.10 in), replace the valve.
# Valve stem end length
Service Limit: 2.5 mm (0.10 in)
VALVE SPRINGS
The force of the coil spring keeps the valve seat tight. A weak-
ened spring results in reduced engine power output and often
accounts for the chattering noise coming from the valve mecha-
nism.
Check the valve springs for proper strength by measuring their
free length and also by the force required to compress them. If
the spring length is less than the service limit or if the force re-
quired to compress the spring does not fall within the specified
range, replace both the inner and outer springs as a set.
" 09900-20102: Vernier calipers
# Valve spring free length (IN & EX)
Service Limit: INNER : 35.0 mm (1.38 in)
OUTER : 38.4 mm (1.51 in)