POWER UNIT 6-17
2. Inspect the intake ports, the exhaust ports, the combustion
chambers and the head surface.
If crack or other damage is found, replace the cylinder head.
INSPECTION / SERVICING
NOTE:
If crack, excessive wear or other damage is found on any com-
ponent, replace.
CYLINDER HEAD
1. Remove all carbon from the combustion chamber.
NOTE:
• Do not use any sharp edged tool to scrape carbon off the
cylinder head or the head components.
• Be careful not to scuff or nick the metal surfaces when
decarboning.
Valve seat
Check the valve seat.
If crack or other damage is found, replace the cylinder head.
Cylinder head distortion
Measure the cylinder head distortion (gasketed surface) at a to-
tal of 6 locations as shown.
$
09900-20803: Thickness gauge
Straight gauge
Service limit: 0.05 mm (0.002 in)
If the measurement exceeds the service limit, resurface or re-
place the cylinder head.
NOTE:
The cylinder head can be resurfaced, using a surface plate and
#400 grit wet sandpaper. Move the cylinder head in a figure
eight pattern when sanding.