Group
21 Engine
.3F{'
'
q.
^s
Cylinder
head, cieaning
-
inspection
F12
Grind-in
valves with
paste
Clean valves thoroushly.
Replacingvalve
seats
OperctionsF
13 21
Valve
guides
must
be replaced before
rep ac_
ing seats, see
F6 8,
page
37.
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
(1.4602
1.4608)
{1.3028-1.3033)
mm
=
0.0029
0 041 in)
Oversize
(replacement
Parts
version)
D ameter, seat
recess,
mm
(rnJ
in1ake....................
37.200-37.216
\1.4646-1.46521
exhausr
..............-- 33.200
33 216
113411-1
30171
intake............-.......37.290
37.305
(1.4681-1.4687)
exhausi...............33.290
33305
(1.3106-1-3112)
When replacing
va ve seals:
the interference
between
the valve seat and
its bore ir the cYlinder
head shall
be
0.074-0.10s
mm
(0.0029-0.0041
in) I e
valve sear
d a-
meter must
be 0.074 0.105
mm
(0
002F0
0041 n)
greater
ihan th€
diameler of the
bore in the
cylinder
head.
Replace cylinder
heacl if c earance
is too smal
Mill seat
recess if interference
is too
large.
39
To Next Page
Loading...
