1980 SKODA 120L fuel pressure

The child'proof
lotch
of
the reor
door.s con
be
"ng"!J Uy
tipPing down
its
lever' The doors
;;; ;" open"d'froir outside
ofter
disengoging
iunfoctin'g1 the
lotch by pulling
the
Press'
button.
Fig.1.311 Inside
Door
Mechonisms
1 -
Hondle
2 -
Lock Press-button
3 -
Drop window cronk
4 -
Door pull
5 -
Ashtroy (depending
on
reor door
outfit) Fig.
1.312
Child'Proof Lotch
INSTRUMENT PANEL
t
a
(
Fis. 1 .3/3 SKODA 1O5
Slnstrument Panel
up
to October 1978
only'I
12
/l
910
1 -
Worning light
of
left-hond direction
indicotors, green
2 -
Speedometer
3 -
Worning light
of right'hond direction
indicotors, green
4 -
High-beom worning light,
blue
5 -
Th6rmometer (of
engine cooling liquid) 6
-
Chorging worning
light, red
7 -
Oil pressure
worning light,
reo
8 -
Distonce recorder
I -
Fuel reserve worning light,
omber
10 -
Broke sYstem
worning light,
red
11 -
Fuel gouge
12 -
UnoccuPied, green

Worrring
lights:
5 -
left-hond direction indicotors, green
6 -
oil pressure,
red
7 -
right-hond direction indicotors, green
8 -
broke system, red
9 -
chorging, red
10 -
fuel reserve, omber
11 -
high beom, blue
The thermometer indicotes the temperoture
of the coolont with the ignition switched on.
The optimum operoting temperoture ronge is
from 75 to 105oC. In
SfOon 105 S, this
ronge
is identified by
the green
zone of the scole.
The fuel gouge
indicotes the level
of the fuel
with the ignition switched on. The scole is
provided with divisions 0 -
r/2
-
1, i. e., empty,
holf full,
ond full
tonk.
The driver is worned by the red worning light
when thene ore less thon 5litres of fuel in the
fuel tonk.
The tochometer indicotes the speed (revol-
utions) of the engine. The
speed should
never
rise to the red zone. When chonging the geors,
on increose of speed within the ronge
of the
yellow zone is permissible.
The porking
lights come on when the switch
is thrown to the first
right-hond position.
The
Fig. 1.3/6 Switches -
port I
1 -
Porking light switch ond feeder of heodlomp
dipswitch
2 -
Horn switch, direction indicotor switch,
ond dipswitch
3 -
Switch of ouxiliory (extro)
heodlomps
4 -
Door switch 12
-
unoccupied, green -
fog lomp worning light
included in speciol
extros
13 -
unoccupied, green -
low-beom worning light
included in speciol
extros
14 -
unoccupied, red
switch switches on the heodlomps, toil lights,
ond the licence plote
light.
The heodlights, i. e. driving (high
beom) ond
dipped (low
beom), ore switched on by throw-
ing the switch to the second
right-hond pos-
ition. The switch switches on oll porking
lights
ond the heodlights
in occordonce with the pos-
ition of the switch stem-type lever: centre
position -
dipped lights,
towords the instrument
ponel -
driving lights. When the
driving lights
ore on, the blue worning light glows.
The ouxiliory heodlomps
come on ofter pull.
ing the switch knob, but only while moin
heod-
lomps ore on.
heodlomp flasher storts floshing
when
the switch lever
toword the steering
ring.
horn is sounded by depressing
the lever
the steering wheel shoft.
Fig.1.317 Switches -
port ll ond oshtroy
1 -
Switchbox ond steering lock
2 -
Switch of windscreen wipers ond
wosher
3 -
Heoter switch
4 -
Switch for on odditionol device -
not
stondord fitted
5 -
Disobility worrning light
switch -
not on
SKoDA 105 s
6 -
Heoter control
7 -
Ashtroy
The
pulling
wheel
The
toword
i
I
L 12

Lifting
the cor with o
Power iock -
When
r-rsing o service
Power iock, let the
cor rest on
the points
shown in Fi1.1.412.
To tow the cor, hook the towing rope on
to
the brocket under
the cor nose. Threod the pin
through the loop of the rope
ond the brocket
lugs ond secure the pin
with o cotter pin (both
thL pin
ond the cotter pin
ore included in the
cor occessories).
1.5 SPARE WHEEL
AND FUEL TANK
Spore wheel -
After having opened the
lug-
goge boot lid, pull the hondle of the spore
wheel corrier releose
rod.
The corrier is
re-
leosed ond swings
down (speciol equipment of
the cor includes
o sofety lotch behind the
bumper which hos to be pushecl
oside to
releose the corrier
) . After
hoving closed the corrier (by
lifting it),
push the releose lever under
the bumper to the
right os for os it will go.
Fuel tonk -
The filler neck with cop is in the
reor on the right-hond
side of the cor- lt con
be locked ond unlocked by meons of
the re'
spective key.
1.6 STARTING THE
ENGINE AND CHECKING
ITS CORRECT RUNNING
1. Moke sure thot the geor
lever is in its
neutrol position,
switch on the ignition (pos-
ition I on the switch box) ond wotch the
coming on of the oil pressure ond chorging
worning lights, i.
e. check the function of the
olternotor -
see the informotion in porogroph
4.
Prepore the engine
to its temperoture:
- Storting from cold in
the occelerotor pedol
- Storting from cold in
the occelerotor pedol
choke for
storting occording
winter -
do not touch
ond use the full choke
summer -
do not touch
ond use only holf of the
Fig. 1.5/1 Hondle ot
Rod (f ronr obove )Spcre
Wheel Lock
crnrl Safety Lotch -
Storting o wormed-up engine -
depress the
occelerotor pedol
slowly to tlre
toe-boord, do
not touch the choke
2. Depress the clutch pedol
(odvisoble
in
summer, necessory in
winter) ond stort
the
engine by turning the ignition key to position
ll.
Let go
of the key os soon os the engine fires
ond releose the occelerotor pedol
{if it hos
been
clepressed).
It the engine ,refuses
to fire, return the key
to the position "0"
ond rePeot the
storting
Pro-
cedure. lf the engine is wormed up, depress the
occelerotor pedol
to obout one third of its totol
trovel. lf the cold engine stolls even
ofter the
second ond third storting ottemPt, enrich the
storting mixture by quickly
depressing the
oc-
celerotor pedol
once or twice to holf of its
trovel during the next storting ottemPt.
Never let tlre storter motor run for more
thon
obout 5 seconds. Woit
some 5 seconds before
repeoting the storting.
Fuel is injected
by every quick
depression of
the occelerotor pedol
ond enriches the mixture
so thot it is difficult to ignite. lf the engine
is flooded, stort
it
with o fully depressed oc-
celerotor pedol.
3. Increose the engine speed corefully while
releosing the clutch pedol. lf the
engine shows
signs of stolling, depress
ogoin the clutch
pedol.
Relecse
L.ever
Fi.1.5t2 Fuel Tcrtrk Filler
Neck
16

ilil
ll
I
Z,l
spring woshers under the pump
fostening nuts.
36. lnstoll the oil filter -
see Oil Filter in
Chopter 15.3.
37. Bolt the brocket ond the reloy lever
of the
occelerotor linkoge to the intoke monifold, Use
spring woshers to lock the bolts in position.
38. Locote the corburettor gosket, sheet
guord, onother gosket,
the insuloting wosher,
ond o third gosket (oltogether
three goskets
of
the some type) on the intoke monifold inlet
socket, instoll the corburettor,
ond tighten
it
down with nuts.
On 105 ond 120 l- engines, the sheet guord
must be fitted to the intoke monifold inlet
socket with o throttling spider, while 120 LS
engines must hove the possoge
unobstructed.
39. Smeor the boll pins
of the linkoge
ond
corburettor lever with greose
contoining molyb-
denum disulphide
ond mount on them the oc-
celerotor link (tie-rod).
Hold the link in pliers
ond slip securing clips over the heods.
Hook o spring on the shonk of the reloy
link-
oge boll pin
ond on the rib of the forehousing
on the corburettor.
40. Screw down the vocuum
control pipe
on
the corburettor (using
double-sided seoling
rings) ond slip on the rubber
hose connecting
the pipe
with the distributor vocuum control
unit. Secure the pipe
by bending the clip under
the nut of the intoke ond exhoust monifold.
To Refit Alternotor
41. Attoch the olternotor
brocket to the side
of the cylinder block while putting
ploin
woshers under
the nuts. Mount the olternotor
holder together with the engine mounting lug
on the bolt of the timing geor
cover ond the
front lug of the cylinder block.
Use self-locking
nuts for the bolts f ostening the olternotor
holder. Lock
the lower bolt of the lug by meons
of o spring wosher
ond nut. Using onother bolt,
bolt together the lug ond the brocket. lnsert
the tie-bolt from
the side
of the lug, slip on
o ploin
wosher ond tighten the nut. Fit the
short-circuit strip on the bolt ond lock it in
o position
porollel
with the olternotor brocket
by screwing
down the respective nut with
o ploin
wosher.
42. Put the olternotor into the holder,
ttrreod
in the bolt, ond screw down the nut with o ploin
wosher without tightening. Without tightening
the self-locking
nut, bolt the strut into the
brocket on the cylinder heod. Swing the olter-
notor toword the engine, fit
the V-belt ond,
while tensioning it, connect the olternotor with
the strut using o bolt, spring wosher ond nut.
At the some time, tighten the nut of the bolt
holding down the olternotor
in the
holder ond
the nut of the bolt connecting the strut with
the holder. For the belt slock odiustment see
Chopter 15.3. 43.
Fosten the second
engine mounting lug
using nuts with spring woshers.
To Fit Cylinder Heod, Air
Cleoner,
ond Sporking Plugs
44. Fit the cylinder heod
with cemented.on
gosket on the cylinder block ofter hoving slip-
ped o seoling ring ond o wosher on eoch bolt,
the some os in the cose of the push-rod
cover.
In oddition, fit the fuel pipe
holder on the reor
bolt ond hold it down by slightly tightening the
nut.
45. Fit the oir cleoner in position
ond fosten
it to the corburettor with o bolt using o seoling
ring ond wosher. Put o spring wosher
under the
nut on the brocket
ond screw down the nut on
the bolt of the cover without ony wosher.
46. Threod the fuel hose through its holder
on the cylinder heod ond use clips to fosten it
to the corburettor ond pump.
Adiust the most
suitoble position of the hose by rototing
the
holder ond then tighten the nut.
47. Attoch hoses connecting the oir cleoner
with the corburettor ond the oil filler neck.
When preporing
the cc for driving in winter,
instoll the winter
oir-intoke tube (hose) -
for
detoiled instructions see Chopter 15.3 "Air
Cleoner -
Winter Operotion".
48. Screw in the sporking plugs
with seoling
iings ond fit the ignition cobles. For the re-
commended types of sporking plugs
see Chopter
13.7.
The outlet on the distributor cop morked with
o notch is intended for
the coble
to cylinder
No. 1. The
remoining outlets ore.to be counted
clockwise ond in direct
order from 1
to 4 ond
the cobles will be connected to sporking plugs
in the order of numbers cost on the cylinder
heod beside the recesses for sporking plugs.
Plug Screws ond Lubricotion
System
Accessories
49. Plug the oil sump with the conicol screw
plug with its
seoling ring. In the cose of on
engine without the oil cooler, plug
the oilwoy
on the timing geor
cover with o screw plug
with o seoling
ring, ond the oilwoy ot the reor
end of the cylinder block with o pressure
switch. lf the socket for screwing down the
pressure switch is missing, instoll o new socket
together with its respective seoling ring.
lf on oil cooler is provided,
hoses ond o press-
ure switch should be
connected to the oilwoys
occording to Chopter 11.9.
Put the oil dipstick
with the f itted rubber ring
in its ploce.
For the type of the dipstick see
Chopter 2.17.
50. Using spring
woshers with the bolts,
screw down the flywheel
guorcl
ofter removing
36

Technical
Description
Car Model 1976/1979 Carburettor type
and model
1979 onwards*
105
120 120 S
and 105 L
L
LS
Types of carburettors and
their functional elements according to
the,polex cdnparison table
or
their bore (in
millimetres) JlKOV32 EDSR
-
443751 290 1
00 JlKOV32 EDSR -
443751 292400
JrKOV32 EDSR -
443751 31 9 800 JlKOV32 EDSR -
443751 292500
J|KOV32 EDSR -
443751290000 J|KOVg2 EnFF -
443751 292600
to
;1
Car model 105S, 1O5L
itZOr- '
l2OLs:
Carburettor type and model Se.B
above
Elements of stage I and ll or in
common
Fge
1 2
1
2
t
2
Atomizer cone diameter
Main petrol jet
Main air jet
Pilot jet
Pilot air jet
Auxiliary pilot jet
Econostat petrol jet
Econostat mixture jet
Econostat air jet
Choke petrol jet
Choke air jet
diameter
Diaphragm control air valve
Pump by-pass orifice
Injector
Needle valve diameter
Suction connection diameter 21
105 170
50
140
60
95/85'70
90
4.5/5.5*
130 40/45*
50 1.5
1.2 22
1 12/1 10*
170 50
140
60
110
70 1 00/90*
4.5/5.5'
160 40/45*
50 22
23
'.112/110*
130/125*
170 50
140
1Orygo*
4.5/5.s*
.80
40/45*
22
120
160 45
1.5
1.2
1,5
1.2 23
125
160 45 160
45
60
Jo
70
1'to
70
50
Jo
*erF
or"fs?
,.w'1'
80
Acceleration pump
discharge
Float weight 2O t 1 gram 7 to 9 c.c.
per
1O strokes (1976-79)
6 to 8.$19f9 onwards)
Fuel level. Float Removed.'28mm t'1mm frEm bp
face
Moin System (Fig.
2.1gl1l
Both mixing chombers hove self-contoined
moin systems. Air is mixed with petrol
in the
emulsion tube ond the finol odiustment
of the
mixture tokes ploce
while it is corried off by
the oir flow with the throttle disc open.
ldle Run ond By-poss System
(Fis.2.19l2l
These ore token core of by two
circuits -
by
the idle run system in stoge I ond the ouxiliory
oir system in stoge ll. Both systems
ore con-
nected to the moin systems
of both stoges in
the zone
of the emulsion orifice
by the re-
spective elements terminoted by the odiustoble
idling screw ond fost-idling (ouxiltory
oir)
screw.
- Stoge
I incorporotes
the petrol
iet seporotor
for the prevention
of self-ignition. The
idling ori-
fice is interconnected with the mixing
chomber
by two by-poss bolts enobling
c smboth tron-
sition to the moin system,
ond o hole is pro-
vided in the mixing chomber to obviote
onyinterference
with the smooth flow ot o hlgtler
underpressure (vocuum).
.
ln stoge ll, the by-poss hole enhonces
o smooth ond continuous intgrconnection
of
both corburettor stoges.
Econostot or rich-mixture syste4
(Fig. 2.19/3)
This system enriches the
mixture in stoge I
ot higher engine lood (output).
lt operotes
outomoticolly occording to the
volue of under',
pressure in the otomizer ond
in dependence onf
the flow of oir sucked-in by
the engine.
Accelerqtion pumP
(Fig. 2.19i5)
This is o mechonicol, diophrogm-type
PumP
controlled by the throttle disc of
stoge
l. Fuel
sucked-in by the diophrogm from the floot
chomber posses
through o non'return boll
volve
to the iniector ond through the
by'poss orifice
bock into the floot chomber. At o sudden open-
ing of the throttle disc,
the moior part
of the
fuel poses
through the
iniector, ot
o slow
opening into the by-poss
without the oction
of the iniector.
60

Choke
-
Cold-storting Device (Fig.2.1916)
Bosicolly, the choke is o self-contoined cor-
burettor consisting of o fuel reservoir, o petrol
jet, on oir
iet, o
vocuum
controller, ond o throttle
volve. The
mixture is formed in the throttle
volve zone where it is sucked
out from under
the corburettor throttle
disc.
At increosing engine speed, the rising vocuum
moves the plunger
of the choke vocuum
control,
the holes in the plunger
overlop ond thus the
mixture is enriched outomoticclly. The driver
controls the richness
of the mixture by opening
or closing the choke throttle volve.
Auxiliory Devices
Vqcuum connection for the vocuum odvonce
control picks
up vocuum (the
underpressure)
obove the throttling disc of stoge
| (see
Fig.
2.1st4).
The suction connecticri is led out of the cor-
burettor lower flonge os o tube from
under the
throttle disc of stoge ll. The
suction prevents
o generotion
of vocuum (underpressure)
in the
Fi1.2.1914 -
Stoge
16 -
Ff oot
chomber cover, 17 -
Floot chomber
body, 18 -
Stoge ll
control, complete, 19 -
Dio-
phrogm spring, 20 -
Diophrogm, 21- Diophrogm
control oir volve -
stoge ll, 21A -
Diophrogm cronkcose
during idle
run ond it removes for
burning ony residues of unburnt
hydrocorbons
which hove got
into the cronkcose.
Fi1.2.1913 -
Econostot -
Rich-mixture System
13 -
Econostot oir
iet, 14 -
Econostot petrol
iet,
15 -
Econostot mixture
iet "2"
I Control Elements
control oir volve -
sttfge l, 22-
Vocuum con-
nection, 1 ST ond 2
ST -
Corburettor stoge I
ond ll i:lrFig.2.
23 -
Inier
pump, c(
Accelerc
venti ng
I
32 and 3
30 -
Chol
Choke vr
volve
CARBUR
AND RE'
Diogno
rect chec
reossemb
62

d)
e) f) choke
plunger
sticking in its
bottom
position storting worm engine
too high fuel level in floot chomber
incorrectly odiusted
idle run unstick
the plunger
or reploce it with
o new one
odjust the
floot
odiust idle
run correctlY
2.2O FUEL PUMP
Technicol DescriPtion
The model JIKOV MF 3407 fuel pump
is of
the diophrogm ond
lever type, controlled by the
round disc of the comshoft. The suction
motion
of the diophrogm is octuoted by the
lever, the
dischorge motion by the spring of
the dio-
phrogm. Fuel flows through o stroiner, o mud
trop, ond the suction volve to the delivery
volve. A priming lever is provided
for hond
priming of the fuel. The moving mechonism
is
lubricoted with oil
sploshed from the cylinder
block. Stroke of the driving disk 4
mm
Suction heod 1.5
mm
Deliveryheod. 2mm
Pump dischorge ot 2,000 strokes
per minute ond free outflowwithout
counter-pressure 30
ltrs/hr.
Mointenonce, Repoirs, Disossembly
ond Reossembly
For routine
mointenonce (cleoning
of the
mud-trop screen) see Chopter 15.3. After hoving
operoted the hond-priming lever lift it
till it
engoges sofely in its locked position.
ln the cose of o defect, inspect the diophrogm
ond check the volves for leokoge. After hoving
removed the pump
from the engine, remove the
mud trop, seporote the upper port
from the
lower port,
ond remove two screws, holding
down the thrust plote,
to lift owoy the volves.
Swill oll ports
in petrol
ond blow off with com'
pressed oir. Reploce domoged ports
with new
ones. lf necessory, remove the diophrogm from the
octuoting lever in
the lower port
of the fuel
pump (its
monufocturer recommends the dio-
phrogm to be reploced ofter obout 50,000 kilo-
rnetres with o new
one). Do not stretch the
spring of the diophrogm ond do not olter its
compression force chorocteristic in ony woy.
Do not forget to put
fibre pocking rings
underthe
volves
when reossembling the
fuel
PumP.
Put o spocer ring under the suction volve (close
to the mud trop). Fig.2.2Ol1 shows
the pos-
itions of volves ond the holding-down thrust
plote. Put the spring
of the diophrogm into
the
lower port
oi the pump
ond engoge the pin
ot
the diophrogm with the octuoting lever. Oper-
ote the hond lever
to compress the dioPhrogm
oncl hold it in position by inserting o
rod of 4.5
to 5 mm diorneter (for
exomple the
shonk of
o drill, etc.) between the octuoting lever
ond
the woll of the pump
lower
Port.
Now bolt both pump
ports
together so thot
the mud trop is on the
right-hond side when
viewing the pump from obove
ond the fostening
flonge from the front. Use spring
woshers
under the clomping bolts.
Fig.2.2011 -
Section Through
Fuel Pump
lf it is necessory to verify
the dischorge of
the pump
by o test, note the following require'
mentswhich the pump
must meet otl80strokes
per minute:
o) 15 ltrs/hr. ot f ree outf low without
fuel
counterpressure
b) minimum pressure
of 0.018 MPo (1.8
m of
woter column) ot
o zero off'toke of fuel
c) o dry pump
must drow fuel from o
depth of
1.5 m in 16 seconds.
Fuel Pump Defects ond Their Removol
1. Foulty fuel
supply
o) clogged mud trop
b) domoged diophrogm
2. Fuel pump
does not hold fuel
o) dirty or defective volves cleon it
reploce it
with o new one
wosh them in petrol,
reploce defective
volves with new ones
66

11.4-11.5
I
I
I
F
r
t'
on to the coolont tonk.
Hose
clips ore formed
either by metol strips
or lengths
of wire. When
tightening the wire clips, toke core not to
domoge the rubber of the hoses.
To Fosten Pipes ond
Hoses
A correct winding of the strip is importont
to ensure o self-locking clomping of the strip
clips -
see Fig. 11.411.
Fig.11.Al1- Diogrom showing
the threoding
of
the clip strip through
the clip closp ond
the
direction of rototion of
the tightening cotter
pin -
the diogrom hos generol
opplicobility
1 -
Strip clip,2 -
Closp, 3 -
Cotter pin
The moin pipeline
routed under the cor f loor
consists of front ond reor pipes.
They ore em-
bedded in o chonnel moulded in the floor
boords ond rest on on insuloting (polysterene)
podding. From below, they ore protected
by
o guord,
the copscrews of which ore locked
in
position by spring woshers.
Use pipe
holders (yokes) to fosten the pipe-
line to the floor. In
the front
ond reor port
of
the cor, tighten
the pipes
over the insulotion
lrod ond insert
spring ond ploin
woshers under
the nuts.
Do not use insulotion pods
for bends
forming the tronsition from
the front
ond reor
lower flot ports.
Use spring woshers under
the
heods of copscrews.
Before instolling the pipes, prepore
ouxiliory
yokes (or use lengths of wires ottoched to the
provisionolly screwed-in copscrews of the pipe-
line guord) to liold the pipes
in the moulded
chonnel in
the floor before
the finol fostening
of their guord.
The woter line runs
under the cor together
with other lines, pull-rods,
etc. For their mutuol
ref otive orrongement see Chopter 12.7. Removol
To moke the underbody occessible for hond-
ling the pipes,
ploce
the cor over o floor pit
or
on o romp. The minimum required cleoronce is
obout 650 mnr.
1. Remo.re the guords
of the pipes
ond the
fuel tonk, lift owoy the spore wheel, ond loosen
the yokes
holding the pipes
to the floor.
2. Remove droin screws to droin the coolont
from the pipes -
see the illustrotion in Chop-
ter 15.'13.
3. Remove one hose clip in the middle
of the
cor to disconnect
the pipes
(ottention -
the
remoining coolont will f low out), ond dis-
ossemble the line.
4. Disconnect the pipe
ends from the hoses,
ond detoch the pipes
from the floor or other
ports of the cor.
5. Pull out the reor pipes
possing
them core-
fully oround the vorious cor ports.
6. Pull out the front pipes.
Turn
the front
wheels into their left lock position,
disconnect
the steering linkoge from the steering
reloy
lever ond the steering knuckle orm of the
right-
hond wheel, ond push
the linkoge ogoinst the
oxle body. While removing the pipes,
rotote the
left-hond pipe clockwise (when
viewing the cor
front end), ond the right-hond pipe
onticlock-
wise.
Reinstollotion Reverse the dismontling procedure
when re-
instolling the woter line. While connecting the
steering linkoge, poy
ottention to the condition
of boll pin
seoling cups (fit
new cups if the old
ore domoged). Fill in the recommended
coolont
ond bleed the cooling system.
11.5 COOLANT TEMPERATURE CONTROL
Throughf low Thermostot
This thermostot shuts off the inlet of the
coolont into the rodiotor
during the engine
heoting-up period. lt is mounted on the engine
- see Chopter 2.3, por.
30.
The thermostot operotes within the following
volues:
it begins to open ot 80+2"C
it is fully open ot 90+4oC
its lift ot full opening
11 mm
When closed, it
is permitted
to let poss
o nroximum
of 0.5 litres
of coolont per
minute,
ond it must not be closed by o bock pressure
of 0.16 MPo (1.6
kg/cm2).
When removing the thermostot by rototing
tlre rivet in the volve disk, breok owoy sedi-
I i
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