9-17
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
• VALVE GUIDE I.D.
1) Before measuring the valve guide I.D., ream the valve
guides to remove any carbon deposits using the special
tool.
Turn the special tool (valve guide reamer, 5.510 mm)
clockwise; never turn it counterclockwise. Continue to turn
it clockwise as you lift it from the valve guide.
TOOL:
Valve guide reamer, 5.510 mm
07984-2000001
2) Measure and record each valve guide I.D.
NOTICE
• VALVE SEAT WIDTH
Measure the valve seat width.
3) If the measurement exceeds the service limit, replace the
valve guide with a new one.
• Check the valve stem-to-valve guide clearance after
replacing the valve guide.
Standard
Service limit
IN/EX
5.500 - 5.512 mm
5.530 mm
(0.2165 - 0.2170 in)
(0.2177 in)
[2]
VALVE
SEAT
TOO
HIGH
[1]
VALVE
SEAT
TOO
LOW
[1]
VALVE GUIDE
REAMER, 5.510 mm
07984-2000001
• VALVE STEM-TO-VALVE GUIDE CLEARANCE
Calculate the gap between the valve stem O.D. and the valve
guide I.D.
Standard
Service limit
IN
0.010 - 0.030 mm
0.060 mm
(0.0004 - 0.0012 in)
(0.0024 in)
EX
0.030 - 0.050 mm
0.100 mm
(0.0012 - 0.0020 in)
(0.0039 in)
If the stem-to-guide clearance exceeds the service limit,
replace the valve and the valve guide as a set (P. 9-19).
Standard
Service limit
IN/EX
1.25 - 1.55 mm
2.00 mm
(0.049 - 0.061 in)
(0.079 in)
If the valve seat width is too wide or narrow, or if the valve seat
is too high or low, recondition the valve seat (P. 9-21).
[3]
VALVE SEAT
WIDTH
120