ENGINE
L4100, WSM
1-S44
(EU)
Correcting Valve and Valve Seat
NOTE
• Before correcting the valve and seat, check the valve stem
and the I.D. of valve guide section, and repair them if
necessary.
• After correcting the valve seat, be sure to check the valve
recessing.
1) Correcting Valve
1. Correct the valve with a valve refacer.
2) Correcting Valve Seat
1. Slightly correct the seat surface with a 1.0 rad (60 °) (intake
valve) or 0.79 rad (45 °) (exhaust valve) valve seat cutter.
2. Resurface the seat surface with a 0.52 rad (30 °) valve seat
cutter to intake valve seat and with a 0.26 rad (15 °) valve seat
cutter to exhaust valve seat so that the width is close to
specified valve seat width (2.12 mm, 0.0835 in.).
3. After resurfacing the seat, inspect for even valve seating, apply
a thin film of compound between the valve face and valve seat,
and fit them with valve lapping tool.
4. Check the valve seating with prussian blue. The valve seating
surface should show good contact all the way around.
9Y1210278ENS0065US0
Valve Lapping
1. Apply compound evenly to the valve lapping surface.
2. Insert the valve into the valve guide. Lap the valve onto its seat
with a valve flapper or screwdriver.
3. After lapping the valve, wash the compound away and apply oil,
then repeat valve lapping with oil.
4. Apply prussian blue to the contact surface to check the seated
rate. If it is less than 70 %, repeat valve lapping again.
IMPORTANT
• When valve lapping is performed, be sure to check the
valve recessing and adjust the valve clearance after
assembling the valve.
9Y1210278ENS0066US0
(a) Identical Dimensions
(b) Valve Seat Width
(c) 0.52 rad (30 °) or 0.26 rad (15 °)
(d) 0.26 rad (15 °) or 0.52 rad (30 °)
(e) 0.79 rad (45 °) or 1.0 rad (60 °)
(A) Check Contact
(B) Correct Seat Width
(C) Check Contact
KiSC issued 08, 2012 A
Summary of Contents for Kubota L4100
Page 1: ...L4100 WORKSHOP MANUAL TRACTOR KiSC issued 08 2012 A...
Page 3: ...I INFORMATION KiSC issued 08 2012 A...
Page 9: ...INFORMATION L4100 WSM I 5 EU 9Y1210278INI0002US0 KiSC issued 08 2012 A...
Page 13: ...INFORMATION L4100 WSM I 9 EU Mid mount type ROPS 9Y1210278INI0006US0 KiSC issued 08 2012 A...
Page 14: ...G GENERAL KiSC issued 08 2012 A...
Page 67: ...1 ENGINE KiSC issued 08 2012 A...
Page 130: ...2 CLUTCH KiSC issued 08 2012 A...
Page 160: ...3 TRANSMISSION KiSC issued 08 2012 A...
Page 161: ...CONTENTS 1 STRUCTURE 3 M1 MECHANISM KiSC issued 08 2012 A...
Page 201: ...4 REAR AXLE KiSC issued 08 2012 A...
Page 202: ...CONTENTS 1 STRUCTURE 4 M1 MECHANISM KiSC issued 08 2012 A...
Page 210: ...5 BRAKES KiSC issued 08 2012 A...
Page 211: ...CONTENTS 1 STRUCTURE 5 M1 2 OPERATION 5 M2 MECHANISM KiSC issued 08 2012 A...
Page 224: ...6 FRONT AXLE KiSC issued 08 2012 A...
Page 225: ...CONTENTS 1 STRUCTURE 6 M1 2 FRONT WHEEL ALIGNMENT 6 M2 MECHANISM KiSC issued 08 2012 A...
Page 245: ...7 STEERING KiSC issued 08 2012 A...
Page 264: ...8 HYDRAULIC SYSTEM KiSC issued 08 2012 A...