Cylinder Head/Valves - KYMCO Agility 125 Service Manual

7

. CYLINDER HEAD/VALVES

TORQUE VALUES
Cylinder head nut
Valve clearance adjusting nut
Stud bolt
SPECIAL TOOLS
Valve spring compressor
TROUBLESHOOTING
• The poor cylinder head operation can be diagnosed by a compression test or by tracing engine
top-end noises.
Poor performance at idle speed
• Compression too low
Compression too low
• Incorrect valve clearance adjustment
• Burned or bend valves
• Incorrect valve timing
• Broken valve spring
• Poor valve and seat contact
• Leaking cylinder head gasket
• Warped or cracked cylinder head
• Poorly installed spark plug
Compression too high
• Excessive carbon build-up in combustion
chamber
2.0kg-m
0.9kg-m
0.9~1.1kg-m
White smoke from exhaust muffler
• Worn valve stem or valve guide
• Damaged valve stem seal
Abnormal noise
• Incorrect valve clearance adjustment
• Sticking valve or broken valve spring
• Damaged or worn camshaft
• Worn cam chain guide
• Worn camshaft and rocker arm
AGILITY 125
Apply engine oil to threads
Apply engine oil to threads
7-2