KYMCO K-XCT 300i Owner's Manual page 146

3. Engine
Poor lubrication pressure
1. Oil level too low
2. Clogged filter or oil passages
3. No use the specified oil
Cylinder Head, Camshaft, and Valves
• The cylinder head can be serviced with the engine installed in the frame. Coolant in
the radiator and water hoses must be drained.
• When assembling, apply molybdenum disulfide grease or engine oil to the valve guide
movable parts and valve arm sliding surfaces for initial lubrication.
• The valve rocker arms are lubricated by engine oil through the engine oil passages.
Clean and unclog the oil passages before assembling the cylinder head.
• After disassembly, clean the removed parts and dry them with compressed air before
inspection.
• After removal, mark and arrange the removed parts in order. When assembling, install
them in the reverse order of removal.
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 bent 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
3-2
K- XCT 300i