Suzuki LT-Z90 Manual page 69

• Remove the oil seal D .
• Remove the other valves in the same manner as described
previously.
CYLINDER HEAD DISTORTION
Decarbonize the combustion chambers. Check the gasket sur-
face of the cylinder head for distortion with a straightedge and
thickness gauge, taking a clearance reading at several places
indicated. If the largest reading at any position of the straight-
edge exceeds the limit, replace the cylinder head.
Cylinder head distortion:
Service Limit: 0.05 mm (0.002 in)
09900-20803: Thickness gauge
VALVE FACE WEAR
The thickness of the valve face decreases as the face wears.
Visually inspect each valve face for wear and replace any valve
with an abnormally worn face. Measure the valve face thickness
T , if it is out of specification, replace the valve with a new one.
Valve head thickness T:
Service Limit: 0.5 mm (0.02 in)
09900-20101: Vernier calipers
VALVE STEM RUNOUT
Support the valve using V-blocks and check its runout using the
dial gauge as shown. If the runout exceeds the service limit,
replace the valve.
Valve stem runout:
Service Limit: 0.05 mm (0.002 in)
09900-20607: Dial gauge (1/100 mm)
09900-20701: Magnetic stand
09900-21304: V-block set (100 mm)
Be careful not to damage the valve and valve stem
when handling it.
ENGINE 3-21