Kubota D1503-M-DI Workshop Manual page 83

03-M-DI Series, WSM
Valve Recessing
1. Clean the cylinder head surface (1), valve face and valve seat.
2. Insert the valve into the valve guide.
3. Measure the valve recessing with a depth gauge.
4. If the measurement exceeds the allowable limit, replace the
valve.
5. If it still exceeds the allowable limit after replacing the valve,
replace the cylinder head.
Factory spec.
Valve recessing
Allowable limit
(1) Cylinder Head Surface
Clearance between Valve Stem and Valve Guide
1. Remove carbon from the valve guide section.
2. Measure the valve stem O.D. with an outside micrometer.
3. Measure the valve guide I.D. with a small hole gauge, and
calculate the clearance.
4. If the clearance exceeds the allowable limit, replace the valves.
If it still exceeds the allowable limit, replace the valve guide.
Factory spec.
Clearance between
valve stem and guide
Allowable limit
Valve stem O.D. Factory spec.
Valve guide I.D. Factory spec.
S-62
DIESEL ENGINE
0.65 (protrusion) to
0.85 (recessing) mm
0.026 (protrusion) to
0.033 (recessing) in.
1.20 (recessing) mm
0.0472 (recessing) in.
(A) Recessing
(B) Protrusion
W1076880
0.040 to 0.070 mm
0.0016 to 0.0028 in.
0.1 mm
0.0039 in.
7.960 to 7.975 mm
0.31339 to 0.314398 in.
8.015 to 8.030 mm
0.31555 to 0.31614 in.
W1077495
KiSC issued 10, 2009 A