
49
2. The lobe heights must be greater 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.
NOTE: If the journals are worn, replace the cam-
shaft.
Inspecting Camshaft Spring/Drive Pin
(Front Camshaft Only)
1. Inspect the spring and drive pin for damage.
CF061A
CF060A
2. If damaged, the camshaft must be replaced.
Installing Top-Side
Components
A. Pistons
B. Cylinders
1. Install the piston on the connecting rod making sure
the circlip on each side is fully seated in the piston.
NOTE: The piston should be installed so the arrow
points toward the exhaust of the respective cylinder.
GZ166
2. Place the two alignment pins into position. Place the
cylinder gasket into position with a drop of silicone
sealant at the front and rear crankcase junction; then
place a piston holder (or suitable substitute) beneath
the piston skirt and square the piston in respect to the
crankcase.
GZ146B
GZ159
3. Lubricate the inside wall of the cylinder; then using a
ring compressor, compress the rings and slide the
cylinder over the piston. Route the cam chain up
through the cylinder cam chain housing; then remove
the piston holder and seat the cylinder firmly on the
crankcase.
CAUTION
The cylinder should slide on easily. Do not force the cyl-
inder or damage to the piston, rings, cylinder, or crank-
shaft assembly may occur.