Valve Seats Inspection - DAELIM HISTORY 125 Service Manual

CYLINDER HEAD / VALVES
● Support the cylinder head and drive the old guides out
of the combustion chamber side of the cylinder head.
TOOL : VALVE GUIDE DRIVER
CAUTION
·Avoid damaging the head when driving the valve
guide out.
● Apply oil to a new O-ring and install it onto a new
valve guide.
● Drive the new guide in from the camshaft side of the
cylinder head while the cylinder head is still heated.
TOOL : VALVE GUIDE DRIVER
● When reaming new valve guides, insert the valve guide
reamer from the combustion chamber side.
NOTE
·Take care not to tilt or lean the reamer in the guide
while reaming.
Otherwise, the valve is installed slanted, that causes
oil leaks from the stem seal and improper valve seat
contact and results in the valve seat refacing not able
to be performed.
·Use cutting oil on the reamer during this operation
·Rotate the reamer clockwise, never counterclockwise
when inserting and removing.
TOOL : VALVE GUIDE DRIVER
● Reface the valve seats and clean the cylinder head
thoroughly to remove any metal particles.
VALVE SEATS
INSPECTION
● Clean all intake and exhaust valves thoroughly to
remove carbon deposits.
● Apply a light coating of Prussian Blue to each valve
face.
NOTE
·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.
9-8
VALVE GUIDE
DRIVER
VALVE GUIDE
REAMER