2--20
62--11161
2.3.1 Cylinder Head And Valves (Continued)
1. Cylinder Head
Surface
(A)
Recess
(B)
Protrusion
2.3.1.c Valve Recessing
1. Clean the cylinder head surface (1), valve face and
valve seat.
2. Insert the valve into the head, making certain that the
valve is fully seated.
3. Measure the valve recession (A) with a depth gauge.
4. If the measurement exceeds the allowable limit, re-
place the valve.
5. If the measurement still exceeds the allowable limit,
replace the cylinder head.
Valve
Recessing
Factory
Specification
0.10 (protrusion) mm to
0.10 (recessing) mm
0.0039(protrusion) in. to
0.0039 (recessing) in.
Allowable Limit
0.30 (recessing) mm
0.0118 (recessing) in.
2.3.1.d Clearance Between Valve Stem And Valve
Guide
1. Remove carbon from the valve guide section.
2. Measure the valve stem O.D. with a micrometer.
3. Measure the valve guide with a small hole gauge, and
calculate the clearance.
4. If the clearance exceeds the the allowable limit, re-
place the valves. If the clearance still exceeds the al-
lowable limit, replace the valve guide.
Clearance
Between
Valve Stem
and Guide
Factory
Specification
0.030 to 0.057 mm
0.00118 to 0.00224 in.
Allowable Limit
0.10 mm
0.0039 in.
Valve Stem
O.D.
Factory
Specification
5.968 to 5.980 mm
0.23496 to 0.23543 in.
Valve Guide
I.D.
Factory
Specification
6.010 to 6.025 mm
0.23661 to 0.23720 in.
