Honda GX270H Manual page 142

62Z7B000.book 11 ページ ２０１２年９月２７日 木曜日 午前１０時２１分
dummyhead dummyhead
The 32° cutter removes material from the top edge
(contact too high).
TOOLS (GX270H):
Cutter holder, 6.6 mm
Flat cutter, 28 mm (32° EX)
Flat cutter, 30 mm (32° IN)
TOOLS (GX390H1):
Cutter holder, 6.6 mm
Flat cutter, 33 mm (32° EX)
Flat cutter, 35 mm (32° IN)
The 60° cutter removes material from the bottom edge
(contact too low).
TOOLS:
Cutter holder, 6.6 mm
Interior cutter, 37.5 mm (60° IN/EX) 07780-0014100
Be sure that the width of the finished valve seat is within
specification.
STANDARD:
SERVICE LIMIT:
Make a light pass with the 45° cutter to remove any
possible burrs at the edge of the seat.
TOOLS (GX270H):
Cutter holder, 6.6 mm
Seat cutter, 27.5 mm (45° EX)
Seat cutter, 29 mm (45° IN)
TOOLS (GX390H1):
Cutter holder, 6.6 mm
Seat cutter, 33 mm (45° EX)
Seat cutter, 35 mm (45° IN)
After resurfacing the seats, inspect for even valve
seating.
Apply Prussian Blue compound or erasable felt-tipped
marker ink to the valve seat. Insert the valve, and snap
it closed against its seat several times. Be sure the
valve does not rotate on the seat.
The seating surface, as shown by the transferred
marking compound, should have good contact all the
way around.
Thoroughly clean the cylinder head to remove any
cutting residual.
Lap the valves into their seats, using a commercially
available valve lapper [1] and lapping compound.
After lapping, wash all residual compound off the
cylinder head and valve.
• Do not push the valve against the seat with force
• Avoid lapping the valve in the same position as it
• Take care not to allow the lapping compound to
Adjust the valve clearance after assembly (page 3-13).
07781-0010202
07780-0012100
07780-0012200
07781-0010202
07780-0012900
07780-0012300
1.0 – 1.2 mm (0.04 – 0.05 in)
2.0 mm (0.08 in)
07781-0010202
07780-0010200
07780-0010300
07781-0010202
07780-0010800
07780-0010400
during lapping. Apply a light pass with the valve
lapper.
causes uneven wear. Lap the valve by turning the
lapper slowly.
enter the gap between the stem and guide.
CONTACT TO STANDARD
VALVE FACE
CONTACT TOO HIGH
07781-0010202
VALVE FACE
VALVE FACE
CYLINDER HEAD/VALVES
CONTACT TOO LOW
VALVE FACE
VALVE FACE
32°
60°
[1]
13-11