Suzuki RA410, Manual

Page: 304 / 761

INSPECTION
Valve Guides
Using a micrometer and bore gauge, take diameter readings on
valve stems and guides to check stem-to-guide clearance.
Be sure to take reading at more than one place along the length of
each stem and guide.
If clearance exceeds limit, replace valve and valve guide.
If bore gauge is not available, check end deflection of valve stem
with a dial gauge instead.
Move stem end in directions
and to measure end deflection.
If deflection exceeds its limit, replace valve stem and valve guide.
Valves
Remove all carbon from valves.
Inspect each valve for wear, burn or distortion at its face and
stem end, as necessary, replace it.
Measure thickness of valve head. If measured thickness ex-
ceeds limit, replace valve.
45
ENGINE MECHANICAL 6A4-45
Item Standard Limit
Valve stem
In
5.465 – 5.480 mm
(0.2152 – 0.2157 in.)
–
diameter
Ex
5.440 – 5.455 mm
(0.2142 – 0.2148 in.)
–
Valve guide
In
5.500 – 5.512 mm
–
I.D.
Ex
(0.2166 – 0.2170 in.)
–
Stem-to-guide
In
0.020 – 0.047 mm
(0.0008 – 0.0018 in.)
0.07 mm
(0.0027 in.)
clearance
Ex
0.045 – 0.072 mm
(0.0018 – 0.0028 in.)
0.09 mm
(0.0035 in.)
Valve stem end deflection
In 0.14 mm (0.005 in.)
limit
Ex 0.18 mm (0.007 in.)
Valve head thickness
Standard Limit
IN 1.0 mm (0.039 in.) 0.7 mm (0.027 in.)
EX 1.15 mm (0.045 in.) 0.5 mm (0.020 in.)