DAELIM VJF125 Service Manual page 143

CYLINDER HEAD / VALVES
TOOLS
VALVE GUIDE REAMER
VALVE GUIDE DRIVER
VALVE SPRING COMPRESSOR
VALVE SEAT CUTTER
TROUBLESHOOTING
Enging top-end problems useally affect engine performance. These can be diagnosed by a compression or leak down test,
or by tracing noises to the top-end with a sounding rod or stethoscope.
Low comperssion
Valves
- Incorrect valve adjustment (see section 3)
- Valve springs damage
- Incorrect valve timing
- Uneven valve seating
Cylinder head
- Leaking or damage head gasket
- Warped or cracked cylinder head
Cylinder, piston (see section 10,11)
Excessive white smoke
Worn valve guide or valve stem
Damaged valve stem seal
Worn or damaged piston ring
10-2
Rough idle
Low cylinder compression
Compression too high
Excessive carbon build-up on piston or combustion
chamber
Excessive noise
Incorrect valve adjustment
Sticking valve or broken valve spring
Damaged or worn camshaft
Loose or worn cam chain
Worn or damaged cam chain tensioner