Checking The Rocker Arms; Removing The Cylinder Heads; Checking The Cylinder Heads - Yamaha EH63 Service Manual

CYLINDER HEAD COVERS, CYLINDER HEADS
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CHECKING THE ROCKER ARMS

1.
Check:
• Rocker arm "1"
Wear/damage/cracks  Replace.

REMOVING THE CYLINDER HEADS

The following procedure applies to all of the cylinder
heads.
1.
Remove:
• Cylinder head
TIP
Set the piston at TDC (top-dead-center) on the compres-
sion stroke.
(Refer to "ADJUSTING THE VALVE CLEARANCE" on
page 2-12.)

CHECKING THE CYLINDER HEADS

The following procedure applies to all of the cylinder
heads.
1.
Check:
• Cylinder head combustion chamber
Check the combustion chamber for carbon depos-
its.
Carbon deposits  Eliminate.
TIP
Be sure not to damage the contact surface of the cylinder.
2.
Check:
• Cylinder head
Cracks/damage around the hole of spark plug 
Replace.
3.
Measure:
• Cylinder head warpage
TIP
Measure the warpage on the contact surface of the cylin-
der head at six points using the straight edge and thick-
ness gauge.
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