Honda WMP20X Manual page 51

c. INSPECTION
• VALVE SPRING FREE LENGTH
Measure the free length of the valve springs.
Standard
34.0 mm (1.34 in)
Replace the springs if they are shorter than the service limit.
• VALVE SEAT WIDTH
Measure the valve seat width.
Standard
0.8 mm (0.03 in)
If the valve seat width is under the standard, or over the service limit,
recondition the valve seat.
• CYLINDER HEAD
Clear off any gasket material from the cylinder head surface.
Check the spark plug hole and valve areas for cracks. Check the
cylinder head for warpage with a straight edge and a feeler gauge.
Service limit
• COMBUSTION CHAMBER CLEANING
Attach a soft wire brush to an electric drill and clean any carbon
deposits from the combustion chamber.
NOTICE
Do not remove the valves from the cylinder head when cleaning the
combustion chamber; this could damage the valve seats.
Do not press the wire brush with force against the combustion
chamber; this could damage the cylinder head.
9-4
Service limit
32.5 mm (1.28 in)
Service limit
2.0 mm (0.08 in)
0.10 mm (0.004 in)
WMP20X
Revised: May 2011 (PSV61YE0600-C)