'61HN252' by American Honda Motor Co. - Page 175 of 540
http://services.honda.com/ServiceManual/SVC_MNL/61HN253/61HN2...
1 of 1
3/9/2008 10:50 PM
[2005-2008] [TRX500 FA/FGA]
CYLINDER HEAD/VALVE/CAMSHAFT
VALVE SEAT INSPECTION/REFACING
INSPECTION
Clean all intake and exhaust valves thoroughly to
remove carbon deposits.
Apply a light coating of Prussian Blue to each valve
seat.
Tap the valve against the valve seat several times
without rotating the valve, to check for proper valve
seat contact.
Remove the valve and inspect the valve seat face.
The valve cannot be
The valve seat contact should be within the speci-
ground. If the valve
fied width and even all around the circumference.
face is burned or
badly worn or if it
STANDARD:
1.0-1.1 mm (0.039-0.043 in)
contacts the seat
SERVICE LIMIT: 1.4 mm (0.06 in)
unevenly, replace
the valve.
If the valve seat width is not within specification,
reface the valve seat.
SEAT WIDTH
Inspect the valve seat face for:
· Uneven seat width:
Replace the valve and reface the valve seat.
· Damaged face:
Replace the valve and reface the valve seat.
UNEVEN SEAT
DAMAGED FACE
WIDTH
· Contact area (too high or too low)
Reface the valve seat.
TOO HIGH
TOO LOW
8-13