Checking And Refining Valve Seat Width; Checking Valve Recessing; Checking Stem Guide Clearance - Kubota D1102-B Workshop Manual

C 019 F01 5
( A) How to repair the valve seat
C
Corrected
(b)
of valve seat
(d) A-0.785 rad.(45°)
-0.262
B
C-1.134 or 1.308 rad.(65
C 019 F016
C 019 F017
(a) Valve contacting width
(cl U ncorrected surface
of va Ive seat
cutter
cutter
rad.(15°)
or 75°) cutter
0

Checking and Refining Valve Seat Width

1) Clean the val ve seat su rface.
2) Measu re the width of the seat usi ng a set of vern ier
cal i pers.
3) Appl y red lead on the val ve to check if the seat is scratch-
ed or not.
• To correct the dimensions of the valve seat usi ng a valve
seat cutter, follow the steps.
1) Use a cutter suitable for the valve guide and the valve
seat. (0.785 rad.(45°),¢8m m(0.315 in.))
2) Grind off the front surface of the valve seat by 0.262
rad. ( 15°), since the seat surface becomes wider than
before.
Grind off the rear surface of the seat by usi ng 1.134 or
3)
1.308 rad. (65 or 75°) cutter to finish the seat 2.1 m m
( 0.0827 i n .) wide.
4) Reface the valve.
C+)

Checking Valve Recessing

1) Clean the face of the val ve.
2) Measu re the si n ki ng with a depth gau ge.
3) I f the measu rement exceeds the al l owa ble l i m i t, repl ace.
(i)

Checking Stem Guide Clearance

1) Remove carbon from the val ve gu i de.
2) Af ter ma ki ng su re th at the val ve stem is straight, i nsert
the val ve i nto the val vegu ide.
3) Measu re the stem gu ide clea rance wi th a d ial gauge.
4) I f the measu rement exceeds the al l owa ble l i m i t, repl ace
the stem gu i de and the val ve.
( Note for replacing )
• I nlet and exhaust valve guide resem ble each other i n
shape. To i nstall them, be su re that they a re on the proper
side.
51
2.1
mm
0.0827
in.
0.04 0.07
to mm
0.0016 0.0028
to in.
· --- - - -----
0.10 mm
0.0039
in.
KiSC issued 09, 2007 A