Honda HRS216PKA Manual page 97

CAM PULLEY/CRANKSHAFT/PISTON/
CYLINDER BLOCK
3. Use the 31° and 60° cutters to narrow and adjust the
valve seat so that it contacts the middle of the valve face.
The 31° cutter removes material from the top edge. The
60° cutter removes material from the bottom edge. Be
sure that the width of the finished valve seat is within
specification.
Always turn the cutter clockwise, never
counterclockwise. Continue to turn the cutter as you
remove it from the valve seat. Always follow the valve
seat cutter manufacturer's instructions.
NOTICE
Avoid removing excess material from the valve seats.
Remove only enough material to clean up the seats, and
avoid going over the valve seat width service limit.
4. Make a light pass with the 45° cutter to remove any
possible burrs at the edge of the seat.
VALVE SEAT WIDTH
Standard
0.7 mm (0.028 in)
1. After resurfacing the seats, inspect for even valve
seating. Apply Prussian Blue or erasable felt-tipped
marker ink to the valve faces.
Insert the valves into the cylinder block; then lift and
snap them closed against their seats several times. Be
sure the valves do not rotate in their seats.
The seating surface, as shown by the transferred
marking compound, should have a good contact all the
way around the valve face.
2. Lap the valves into their seats using a 4 mm tube and
some commercially available lapping compound.
NOTICE
To avoid severe engine damage, be sure to remove all
lapping compound from the cylinder block before
assembly.
3. Check the valve clearance after reassembly
9-12
Service limit
1.8 mm (0.07 in)
(P. 3-12).
HRS216PKA • HRS216SKA • HRS216VKA
CONTACT TOO HIGH
CONTACT TOO LOW
VALVE SEAT CUTTER
(commercially available)
0.7 mm (0.28 in)
4 mm TUBE
(commercially
available)
31°
60°