DAELIM NS125DLX Service Manual page 93

● Remove the valve, and check the status of the seat
contact, with a light coating of prussian blue applied
to the valve face.
● If the valve seat is damage, make necessary repair.
If the valve is tilted, check the clearance between
the valve guide and stem. Replace the valve guide
if the clearance is abnormal.
NOTE
•Valve cannot be corrected. If the valve face is
seized, excessively worn, and if the contact is
poor, change the valve.
● Measure the valve seat width.
Standard value: 0.8-1.0mm(0.031-0.039in)
Service limit: 1.4mm(0.055in)
Valve Seat Cutter
● Repair the damaged valve seat by using valve
seat cutters and grinders.
NOTE
•Follow the seat cutter user's manual.
Valve Seat Repair
● If the seat surface is rough or otherwise damaged,
use a 45° cutter to grind the surface.
NOTE
•Grind the seat surface after the valve guide is
replaced.
● Correct the plane slightly using a 37
◦
cutter.
Cylinder Head/Valve
Valve seat
○
45
○
37
Roughness
○
37
○
55
9-9