ENGINE
c. Servicing
1) Cylinder Head and Va l v e
(A) Cylinder Head Surface Flatness
1. Throughly clean the cylinder head surface.
2. Place a straight edge on the cylinder head and
measure the clearance with a feeler gage as
shown in the figure.
3. If the measurement exceeds the allowable limit,
replace the cylinder head.
I M P O RTANT :
• Do not place the straight edge on the combustion
c h a m b e r.
(B) Cylinder Head Surface Flaw
1. Prepare an air spray red check.
2. Clean the cylinder head surface with the detergent
( B ) .
3. Spray the cylinder head surface with the red
permeative liquid (A).
4. Wash away the red permeative liquid on the
cylinder head surface with the detergent (B) after
ten minutes.
5. Spray the cylinder head surface with the white
developer (C).
6. If any flaw is found such as a red mark, replace
the cylinder head.
( A )
Red permeative liquid (B)Detergent (C)White developer
(C) Valve Stem Clearance
1. Remove the carbon from the valve guide.
2. Measure the valve stem O.D. with an outside
m i c r o m e t e r.
3. Measure the valve guide I.D. of cylinder head, and
calculate the clearance.
4. If the measurement exceeds the allowable limit,
replace the valve guide of the valve.
Factory
0.040 to 0.071mm
Valve stem spec.
0.00157 to 0.00276in.
clearance
Allowable
0.1mm 0.0004in.
limit
Valve guide Factory
8.015 to 8.030mm
bore I.D.
spec.
0.31555 to 0.31614in.
Valve stem Factory
7.9760 to 7.975mm
O.D.
spec.
0.31339 to 0.31398in.
0.05mm
Flatness
Allowable limit
0.0019in.
