Servicing - wsm L503 Workshop Manual

L3130 · L3430 · L3830 · L4630 · L5030, WSM

(3) Servicing

(A) Cylinder Head and Valves
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 feeler 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
Factory spec.
flatness
Cylinder Head Flaw
1. Prepare an air spray red check (Code No. 07909-31371).
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 red 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, 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,
correct the valve seat face of the cylinder head with a valve seat
cutter (Code No. 07909-33102) or valve seat grinder.
6. Then, correct the cylinder head surface with a surface grinder, or
replace the cylinder head.
Factory spec.
Valve recessing
Allowable limit
(1) Cylinder Head Surface
1-S44
ENGINE
0.05 mm / 500 mm
0.0020 in. / 19.69 in.
W1027737
(3) White Developer
W1076542
0.05 (protrusion) to
0.15 (recessing) mm
0.0020 (protrusion) to
0.0059 (recessing) in.
0.40 (recessing) mm
0.0157 (recessing) in.
(A) Recessing
(B) Protrusion
W1076880
KiSC issued 02, 2007 A