Suzuki 2000 Grand Vitara SQ625 Service Manual page 468

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.
Valves
1. Valve head thickness
D Remove all carbon deposits from valves.
2. 45_
D Inspect each valve for wear, burn or distortion at its face and stem,
D Measure thickness of valve head. If measured thickness exceeds
D Inspect valve stem end face for pitting and wear. If pitting or wear
D Check each valve for radial runout with a dial gauge and "V" block.
Item
In
Valve stem
diameter
Ex
Valve guide In &
I.D. Ex
In
Stem-to-guide g
clearance
Ex
replace as necessary.
limit, replace valve.
Item Standard
1.0 mm
In
(0.039 in.)
1.2 mm
Ex
(0.047 in.)
is found there, valve stem end may be resurfaced, but not too
much to grind off its chamber. When it is worn out too much that
its chamber is gone, replace valve.
To check runout, rotate valve slowly. If runout exceeds its limit, re-
place valve.
Limit on valve head radial runout:
0.08 mm (0.003 in.)
ENGINE MECHANICAL (J20 ENGINE) 6A4-49
Standard
5.965 – 5.980 mm
(0.2348 – 0.2354 in.)
5.940 – 5.955 mm
(0.2339 – 0.2344 in.)
6.000 – 6.012 mm
(0.2362 – 0.2366 in.)
0.020 – 0.047 mm
(0.0008 – 0.0018 in.)
0.045 – 0.072 mm
(0.0018 – 0.0028 in.)
Limit
0.6 mm
(0.024 in.)
0.7 mm
(0.028 in.)
Limit
–
–
–
0.07 mm
(0.0027 in.)
0.09 mm
(0.0035 in.)