6. CYLINDER HEAD/VALVE SYM
6-2
PRECAUTIONS IN OPERATION
General Information
This chapter is contained maintenance and service for cylinder head, valve, and camshaft
as well as valve rocker arm.
Cylinder head service cannot be carried out when engine is in frame.
Specification unit:
mm
Item Standard
Limit
Compression pressure
13 kgf/cm²
-
Intake 25.965
25.290
Camshaft
Height of cam lobe
Exhaust 25.81
25.120
ID of valve rocker arm
10.00
10.000~10.015
Rocker
arm
OD of valve rocker arm shaft
10.00
9.985~10.00
Intake 5.00 4.975~4.99
OD of valve stem
Exhaust 5.00 4.97~4.98
OD of Guide
5.00
5.030
Intake 0.020~0.045
0.080
Clearance between
valve stem and guide
Exhaust 0.030~0.057
0.100
Outer 32.56
32.26
Free length of valve
spring
Inner 35.25 34.75~35.75
Valve
Valve seat width
1.000
1.600
Connection Flatness of cylinder head
- 0.050
Torque Value
Cylinder head cover bolts
0.8~1.2kgf-m
Holder nuts
1.0~1.5kgf-m
Cylinder head bolts
0.8~1.2kgf-m
Valve adjustment fixing nuts
1.0~1.5kgf-m
Camshaft chain auto-adjuster bolts
0.8~1.2kgf-m
Timing gear cover bolts
0.7~1.1kgf-m (apply with oil on bolt thread & seat)
Spark plug
1.0~1.4kgf-m
TOOLS
Special service tools
Valve reamer: 5.0mm
Valve guide driver: 5.0mm
Valve spring compressor
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