Kubota WSM B2050 Workshop Manual page 133

B2050, B2350, B2650, B3150, WSM
Cylinder Head Surface Flatness
1. Clean the cylinder head surface.
2. Place a straightedge on the cylinder head's four sides and two
diagonal as shown in the figure.
3. Measure the clearance with a thickness gauge.
4. If the measurement exceeds the allowable limit, correct it with a
surface grinder.
IMPORTANT
• Do not place the straightedge on the combustion chamber.
• Be sure to check the valve recessing after correcting.
Cylinder head surface
Allowable limit
flatness
Cylinder Head Flaw
1. Prepare an air spray red check.
2. Clean the surface of the cylinder head with detergent (2).
3. Spray the cylinder head surface with the red permeative liquid
(1). Leave it five to ten minutes after spraying.
4. Wash away the read permeative liquid on the cylinder head
surface with the detergent (2).
5. Spray the cylinder head surface with white developer (3).
6. If flawed, it can be identified as red marks.
(1) Red Permeative Liquid
(2) Detergent
Valve Recessing
1. Clean the cylinder head surface, the valve face and the 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 specification
Valve recessing
Allowable limit
(1) Cylinder Head Surface
1-S44
ENGINE
0.05 mm
0.002 in.
9Y1210982ENS0076US0
(3) White Developer
9Y1210982ENS0077US0
0.050 (protrusion) to
0.25 (recessing) mm
0.0020 (protrusion) to
0.0098 (recessing) in.
0.40 (recessing) mm
0.016 (recessing) in.
(A) Recessing
(B) Protrusion
9Y1210982ENS0078US0
KiSC issued 03, 2014 A