29
1. Using a valve spring compressor, compress the valve
springs and remove the valve cotters. Account for an
upper spring retainer.
KM717A
2. Remove the valve seal, valve springs, and the lower
remaining spring seat. Discard the valve seal.
NOTE: The valve seals must be replaced.
3. Invert the cylinder head and remove the valves.
Measuring Valve Stem/Valve Guide
Clearance
1. Using a micrometer, measure the valve stem outside
diameter; then using a suitable snap gauge and
micrometer, measure the valve guide inside diameter.
2. Acceptable clearance must be within specifications.
Inspecting Valve Face
Inspect the valve face for pitting, grooving, or discolor-
ation. Replace any valve that is damaged.
CYLINDER HEAD ASSEMBLY
NOTE: If the cylinder head cannot be trued, it must
be replaced.
Cleaning/Inspecting Cylinder Head
1. Using a non-metallic carbon removal tool, remove
any carbon build-up from the combustion chamber
making sure not to nick, scrape, or damage the com-
bustion chamber or the sealing surface.
2. Inspect the spark plug hole for any damaged threads.
Repair damaged threads using a “heli-coil” insert.
3. Place the cylinder head on the surface plate covered
with #400 grit wet-or-dry sandpaper. Using light
pressure, move the cylinder head in a figure eight
motion. Inspect the sealing surface for any indication
of high spots. A high spot can be noted by a bright
metallic finish. Correct any high spots before assem-
bly by continuing to move the cylinder head in a fig-
ure eight motion until a uniform bright metallic
finish is attained.
Measuring Cylinder Head
Distortion
1. Remove any carbon buildup in the combustion
chamber.
2. Lay a straightedge across the cylinder head; then
using a feeler gauge, check the distortion factor
between the head and the straightedge.
3. Maximum distortion must not exceed specifications.
CC141D
Measuring Camshaft Lobe Height
1. Using a calipers, measure each cam lobe height.
ATV1013A
2. The lobe heights must not be less than minimum
specifications.
Inspecting Camshaft Bearing
Journal
1. Inspect the bearing journal for scoring, seizure
marks, or pitting.
2. If excessive scoring, seizure marks, or pitting is
found, the cylinder head assembly must be replaced.
Measuring Rocker Arm/Shaft
Clearance
1. Using a dial calipers, measure the inside diameter of
the rocker arm; then measure the outside diameter of
the rocker arm shaft.
2. Acceptable clearance must not exceed specifications.
CAUTION
Water or parts-cleaning solvent must be used in con-
junction with the wet-or-dry sandpaper or damage to
the sealing surface may result.
