Kubota D1803-CR-E4 - Checking Valve Recessing; Adjusting Valve Lapping

5. Apply
the white developer (3) on the cylinder head
surface.
NOTE
• If you
found a red flaw, replace the cylinder
head.
(1) Red permeative liquid
(2) Detergent
(3) White developer
7.4 Checking valve recessing
Tools required
• Depth gauge
1.
Clean the cylinder head surface (1), valve face and
valve seat.
2. Set the valve into the valve guide.
3. Measure the valve recessing with a depth gauge.
NOTE
• If
the
measurement is more than the service
limit, replace the valve.
• If it stays more than the service limit after
you replace the valve, replace the cylinder
head.
Valve recessing
Service specifi-
cation
0.65 to 0.85 mm
0.026 to 0.033 in.
Service limit
1.20 mm
0.0472 in.
(1) Cylinder head surface
(A) Recessing
(B)
Protrusion
7.5 Adjusting valve lapping
Tools required
• Compound
•
Valve lapping tool
• Prussian Blue
1. Apply the compound equally to the valve lapping
surface.
2. Put the valve into the valve guide. Lap the valve on
its seat with a valve lapping tool.
3. After you lap the valve, clean away the compound
and apply oil, then lap the valve again with oil.
4. ENGINE
SERVICING
7. Servicing
4-164
D1803-CR-E4,D1803-CR-TE4,D1803-CR-TIE4,V2403-CR-E4,V2403-CR-TE4,V2403-CR-TE4BG,V2403-CR-TIE4
KiSC issued 12, 2018 A