Grind-In Valves With Paste; Clean Combustion Chamber - Volvo D 20 Service Manual

Group 21 Engine
. 3 F { '
'
q.
^s
Cylinder head, cieaning - inspection
F12
Grind-in valves with paste
C l e a n v a l v e s t h o r o u s h l y .
Replacingvalve seats
OperctionsF 13 21
V a l v e g u i d e s m u s t b e r e p l a c e d b e f o r e r e p a c _
i n g s e a t s , s e e F 6 8 , p a g e 3 7 .
Cfean combustion chamber
F13
Toge ol seal nJsl be clear v vis:ole ahF' cleaninS.
Remove valve seat
F14
Mill vave seat, using cutters such as Mira {P/N
9986045). Refer to manufacturer's instructions. Make
sure that seat in cylinde. head is not darnaged.
clean surfaces thoroughtr.
,rU
Measure diameter of seat recess in cylinder head
and of valve seat
Use an internal micromeier to measure seat recess
Standard
(production version)
Diameter, seat recess, mm (in)
in1ake....................
37.000 37.016 i.1.4561-1.4513)
exhaust ................
33-000-33.01 6 11.2992 1.2994)
inrake.................... 37.09(F37.105
exhausr ................ 33.090-33.1
05
( 1 . 4 6 0 2 1 . 4 6 0 8 )
{ 1 . 3 0 2 8 - 1 . 3 0 3 3 )
mm = 0.0029 0 041 in)
Oversize
( r e p l a c e m e n t P a r t s v e r s i o n )
D a m e t e r , s e a t r e c e s s , m m ( r n J
i n 1 a k e . . . . . . . . . . . . . . . . . . . . 3 7 . 2 0 0 - 3 7 . 2 1 6 \ 1 . 4 6 4 6 - 1 . 4 6 5 2 1
e x h a u s r . . . . . . . . . . . . . . - - 3 3 . 2 0 0 3 3 2 1 6
1 1 3 4 1 1 - 1 3 0 1 7 1
i n t a k e . . . . . . . . . . . . - . . . . . . . 3 7 . 2 9 0
3 7 . 3 0 5
( 1 . 4 6 8 1 - 1 . 4 6 8 7 )
e x h a u s i . . . . . . . . . . . . . . . 3 3 . 2 9 0
3 3 3 0 5
( 1 . 3 1 0 6 - 1 - 3 1 1 2 )
W h e n r e p l a c i n g v a v e s e a l s : t h e i n t e r f e r e n c e b e t w e e n
t h e v a l v e s e a t a n d i t s b o r e i r t h e c Y l i n d e r h e a d s h a l l b e
0.074-0.10s mm (0.0029-0.0041 in) I e valve sear d a-
m e t e r m u s t b e 0 . 0 7 4 0 . 1 0 5 m m ( 0 0 0 2 F 0 0 0 4 1 n )
g r e a t e r i h a n t h € d i a m e l e r o f t h e b o r e i n t h e c y l i n d e r
h e a d . R e p l a c e c y l i n d e r h e a c l i f c e a r a n c e i s t o o s m a l
M i l l s e a t r e c e s s i f i n t e r f e r e n c e i s t o o l a r g e .
39