KYMCO ADG5, Руководство пользователя

Страница: 80 / 426

4. Engine XCITING 400i/XCITING S 400
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
4‐2