Table of Contents
Advertisement
8. Remove the rocker arm casing and the rocker
arm shaft. Lift out
the push
rods. Unscrew the
bo lts for
the
cyl1
inder head and lift oH
the
heod.
R,emove the
man,ifo
ld from the cyl,inder head.
9.
Recondi·
t
ion
the
va lve
system accord
ing
to the
desor ipt ion g
iven unde
r
the head ing
"Cylin
der
Head and
Valves".
Fitting the cylinder head
l.
Check
·
t o
make
sure
that
the cyrl r inder
head
and
block as we
il
as the
piston
s and cyl inder
lin
ers
are dean.
Check
that the o ilway (Fig.
2-18)
for the rocker
arm mechan ism is
clean
on the
i
t appet side. In
the
cyli
nder he'ad theoil goes up through the bolt
hole,
between the
bol.
t and the
waH
cavity
and
then throug
h
an ob liq ue
drill.in
g to the attaching
bolt for the rocker arm sh af t
a
nd
final ly up the
shaft.
Mount the manifold
on
to the
cylinder
head.
Place
th
e
cyl inder
head
gasket and cy·l inder he·ad
in
posi1
tiorn.
(Dowel
pins SYO 2435 can be
su
itably
used for
this
purpose.
)
Fit the bo lts and t ighten
then
a·coord
in
g
to
t he
tightenin
g sequence given
in Fig. 2-17.
N.B. The
bolts
should
be
tig hte ned
in two stag
es.
2. Fil
t
the
push ro
ds
in
pos ition
a
nd mount th
e rocke
r
arm mechanism.
Ad just
the valve clearance,
.50-
.55 mm
(.020-
.022")
for both the
exhaus.f
and
in
-
ta
ke
valves.
3.
Fit
the Tocke'r
orm
casing.
Fit
the
a
lternator
ten
-
sioningi
ron
to the
cy~ind
er
head.
4.
Fit
the rnuts
for
the exhaust
ma,nifol·d
flange
and
aho
t
he
pre
heating
plate.
5.
Fit
the throttle controi and choke wire,
a lso
con-
nect dl
hoses
to
the
intake manifol,d
and car-
burettors. Filt the air deaner
cover
with hoses.
6. Connect the
ignit
ion leads ond e·lectriccable
for
the
temperature
telii-tale.
7.
Flit
the
hosefor
the
heater contro,l
valve and the
upper radiator
hose. Fill with
,coolant.
8. Check the function and also for
leakage.
Fill
if
necessary with
coo
lant.
Adjust the valve dearance
if required.
The
cylinde1
r
head
bolts need not be
subsequenttly tightened.
CYLINDER HEAD AND VALVES
Dismantling
l. Remove
the
va'lve
spr:ings
by
first compressing
them with valve pliers and removing the valve
collets, af
ter which
the
p~iers
are released.
P·lace
the valves
in
order in a valve rack. Remove the
valve
glJide seais.
2.
Measure
the dearance between the
stem
and
Fig
.
2-20.
Valve seat
width
A=2
mm
(.08")
guide.
The
clearance
wi,
t h a new va,lve must not
exceed
.15
mm (.006").
A·lso
check that the valves
are not
exce,ssive·ly
worn. See
"Specification
s"
under
the headings "Valve System" and "Wear
To
le
rances".
Cleaning
With
rota
tin
g
brushes dean the
va
lves,
the
combust ion
cha·mb
ers a
nd th
e oi.lways from
cO'rbon
and combus-
t ion deposits.
Grinding the valves and valve seats
l
.
Grind
the va·lves in
a
machine ofiter they have
been
cleaned.
F·it
new
valves
if the old
ones are
excessive,ly
worn.
2.
Grind
the
va'lve
seats.
Use
an e leotr
icaHy
driven
glrinder or
a
hand milHng
cutter. A
pilot
sp
indl
e
must be
ca·refully
fitte1
d before work is
sta'rted and
any worn
gUI~des
mu,
s t
be repl'aced with new ones.
The
seal
t should be ground until
(l
good
sea,ling
surface
is
obtoined. The angle is 45° and the
width of
the
sealing
surface
is
approx. 2
mm
(.08"), see "A" Fig. 2-20.
If
the
senling
surface
is
too wide after g·rinding,
it
can be re,duced by
u·
s ing a 70° g'rinding stone from the
ini
s
ide
and a
20°
grindingstone from the outside.
3. Coat the
va·lve
sealing
surfa'
c
e'
s with a
·
t hin
layer
of fine grinding paste and
lap
in the valves
against
their
seats.
Then dean the
vol ves
and seats and aheck tbat
gO'od sealing
i,
s obtained.
Replacing the valve guides
l. Press out the old
guides wirth
'f1ool SYO 2818.
2. Press in the new guides
using
drift SYO 2819,
which gives
the
correct pressing-in depth.
See
Fig. 2-21.
3. Check that the guides a.re free from burr and that
the
valves move
easily
in
them
.
2
:
11
Advertisement
Table of Contents
