Valve Seat Cutter - DAELIM VJF125 Service Manual

CYLINDER HEAD / VALVES
70
IN : 22mm
EX : 22mm
IN : 24.5mm
EX : 24.5mm
10-8
20
IN : 23mm
EX : 20mm
VALVE SEATS INSPECTION / REFACE
Clean all intake and exhaust valves thoroughly to
remove carbon deposits.
Apply a light coating of Prussian Blue to each valve
face.
Tap the valve against the valve seat serveral times with
the valve guide reamer, without rotating the valve, to
check for proper valve seat contact.
Remove the valve and inspect the valve seat face.
The valve seat contact should be within the specified
width and evenly all around the circumference.
If the valve seat width is not within specification,
reface the valve seat.
Valve faces cannot be ground. If a valve face is rough,
worn unevenly, or contacts the seat improperly, the
valve must be replaced.
Measure the valve seat width.
STANDARD VALUE : 0.7~0.9 mm
SERVICE LIMIT : 1.3 mm

VALVE SEAT CUTTER

Reface the worn valve seat by using valve seat cutters
and grinders.
Follow the refacer manufactuer's operating
instructions.
Be careful not to grind the seat more than necessary.
CYLINDER HEAD ASSEMBLY
Install new stem seals and valve spring seat.
Lubricate each valve stem with molybdenum grease
and insert the valve into the valve guide turning it
slowly to avoid damage the stem seals.
Check to see if the valve move up and down smoothly.