1979 Citroen CX engine

Downloaded from www.Manualslib.com manuals search engine 2 OPERATION No MA. 142.000 : ~<,n<, rorhurn/io,i.
This kit also contains o set of plugs SOLEX carburettors :
a b
Q Protective plug for sunken mixture adjustment screw
b Protective cap for mixture adjustment screw with collar
C - ProtectiGe cap for throttle spindle stop screw
The Replacement Parts Department supplies cops in packets of 10, under the following refrence nos :
Protective cop for sunken mixture adjustment screw :
SOLEX carburettor 5 489 718 Y (white)
WEBER
carburettor 5 489 716 B ( block)
- Protective cap for mixture odiustment screw with collor :
SOLEX carburettor . 5 501 075 U (white )
- Protective cop for throttle spindle stop screw :
SOLEX carburettor 5 507 643 K (white )
IJTILIZATION
I. REMOVING AND FITTING A PROTECTIVE PLUG FOR SUNKEN MIXTURE ADJUSTMENT SCREW ON A
WEBER OR SOLEX CARBURETTOR (
plug ( a ) ).
NOTES :
1 On GS vehicles fitted with a WEBER carburettor, it is necessary to ~emcwe the air-filter to carry out this
operation.
2 On GS vehicles fitted with a twin-choke SOLEX carburettor, it is advisable to remove the throttle closing
dashpot.
3 - On all 2 CV vehicles, Mehari and 250/400 vans, it is necessary to ~emcwe the air filter to facilitate the
use of the tool.
4 - On CX vehicles fitted with a WEBER carburettor, lower the supporting clamp for the hose to allow the tool
to be aligned
REMOVAL.
1. Load gun A on tool 8.

Downloaded from www.Manualslib.com manuals search engine OPERATION ND MA. 142.000 : ( ,<,,,<~d ,rr,t,,rvc 0, ,,I<> rnrh,!ra/io?r.
Op. MA. 142.000
3
I I
”
. /.
I’,
A
D
A
2. Pierce plug ( Cl ) :
SO,.EX rarl,,,rrrtor :
Position tool C and hold it against gun A.
Position the gun and tool assembly against
plug ( a ) making sue that the nozzle of gun
A
is pro$erly centred against the plug, and that
the assembly is aligned (IS precisely as possible
in the axis of the plug.
-Actuate the gun, and remove it, leoving?oool C
on the carburettor.
Position and hold tool
D against gun A.
Position the gun and tool assembly against
plug ( CI ) moking sure that the nozzle of the
gun is properly centred against the plug, ond
that the assembly is aligned as precisely as
possible in the axis of the plug.
Actuate the gun, and screw the tool into the
plug (L.H. thread ).
- Remove the gun leaving tool
D on the carburettor.
3.
Remove plug ( Q ) :
Load gun A.
- screw tool C in,<, I/><, lmrk of gun A.
- Actuate the gun to remove the plug.
Screw tool
D i,,fr, th<, bnrk of gun A.
Actuate the gun to remove the plug.
4.
Adiust the level of pollution :
NOTE : If the air filter has been removed, f CS
nvd 2 (.v rchirlcs 1 refit it withoot s<,crrring il
so as to carry out the adjustment.

Downloaded from www.Manualslib.com manuals search engine 4 OPERATION No MA. 142.000 : ( ,C,,<.IN/ ,<,“/,,,l’ 0, I/T<’ < o,h,,rntio,,
1
FITTING.
5. Fit the tamper-proof protective plug ( a ) :
Loud gun A.
Screw tool E onto qun A.
Position plug ( a ) in its housing on the
carburettor. ",i n MEHIJK rnr-hrc//or make
SNI“ it is /ill<~ii /he rig/,/ t1 n, I-O!,iili ( S?C
dingrrr,* lx/<,,, I.
Actuate the gun until the plug is properly
located.
NOTE : If the air filter has been removed, refit
it and \(- i/ ~~rwm~r,/I\-.
a
II, REMOVING AND FITTING THE PROTECTIVE CAP FOR THE MIXTURE CONTROL SCREW WITH COLLAR
ON A SOLEX CARBURETTOR ( cap (
b) )
b
REMOVAL.
1. Break the head of cap (
b ) using tool F
If this value is not obtained, unscrew the mixture
control screw.

Downloaded from www.Manualslib.com manuals search engine OPERATION N” MA. 142.000 : c ,, P)C rni ,t n i,,, <‘ 0, I/?< < rirheri,/irin.
Op. MA. 142.000
5
2
:
m
2
-
b E
*
2. Extract cop ( ly) :
- Load gun A.
Screw tool G onto the gun.
Place the tool and gun assembly against the cop
Make sure alignment is correct.
Actuate the gun and remove the cop.
FITTING.
3.
~re-rno~ cap ( b) :
(See fig. I of diagram below )
Fit cap into the collar of the mixture control
screw.
Load qun
A.
Screw tool E onto the wn
Place the tool and gun assembly against the cop
’ 1 1 Actuate the gun once.
4. Adjust the exhaust emission.
I
5. ~nop cop (
b ) into position :
Load the gun. and (~ctuote it o second time onto
the cop to set it in position as per fig. 2 of dio-
gram below.

Downloaded from www.Manualslib.com manuals search engine 6 OPERATION No MA. 142.000 : c ,Pi,r,rol ,cn,,,,cs 0, Ihc ~rwh,,m/ir,n.
III. REMOVING AND FITTING THE PROTECTIVE CAP FOR THE THROTTLE SPINDLE ON A SOLEX
CARBURETTOR (cap ( c ) ).
This operation is to be carried out only in the case of a check and odiustment on o carburettor test bench
(L’POLLU 2000 type ).
REMOVAL.
1, Remove cop ( c ) using flat-nose pliers.
2. Adjust the butterfly opening :
Adjust the butterfly opening using the test bench
according to the Norms laid down in the (< Etudes
Equipement 1) Nos : 14-1116 ter, and 14-l/16
quater, f SC,,, o>r rcc/ucs, ,o Ihr ,,scrs o, r-ml>,,-
~Cf,Ol /es, bcorhcs i.
FITTING.
3.
Fit cop ( c ) :
Load gun A.
- Screw tool H onto the gun.
Fit cop ( c ) onto the throttle spindle stop
screw.
Place the tool and gun assembly against the
cop ( C ) and actuate the gun.

Downloaded from www.Manualslib.com manuals search engine OPERATION No MA. 142-000 : Gcnrrd 1.cnturcs 01. the cnrfxrr~tion. Op. MA. 142-000 7
In order to conform to current regulations, checking and adjustment the exhaust emission on u Petrol )) vehicles must
without fail be carried out after the following operations :
I. REPLACEMENT OF ENGINE.
II. REPLACEMENT OF CARBURETTOR.
Ill. WORKING ON THE CARBURATION
- Replacing the components of the carburettor
- Adjusting the carburettor
- Worki? - rri the carburettor controls
IV. WORKING ON THE INLET SYSTEM
Replacing or removing the following :
the inlet manifold,
- the air-filter,
- the crankcase gases recycling system.
V. WORKING ON THE ENGINE
Adjusting the rocker arms
Replacing or removing the following :
the cylinder head,
- the camshaft,
- the rockers,
- the valves,
_ the barrels and pistons.
VI. WORKING ON THE IGNITION
- Replacing or reconditioning the distributor ( partly or cpmpletely )
~ Adjusting or replacing the spark plugs
- Adjusting the ignition timing
VII. WORKING ON THE EXHAUST SYSTEM
Replacing or removing the following :
- the exhaust manifold,
- the exhaust pipe, or any other section of the exhaust system.
VIII. WORKING ON THE ANTI-POLLUTION SYSTEM
When the vehicle is fitted with special equipment C I c,hic-1~s /or SWIIllI:‘S. Al'S7'KAl.l~ll m;d JAI'A.\. /ot

Downloaded from www.Manualslib.com manuals search engine CARBURATION
OPERATION No MA. 142.00 : Cl~nroricrirtir-s mid .sprrinl ,cnhrcs oi /he cnrh,,wt/or Op. MA. 142.00 1
ENGINE M20/616
I
WEBER CARBURETTORS
34 DMTR 25/200 IDENTIFICATION MARK W 55.00 c:?( 2000 -71 1976
34 DMTR 25/250 IDENTIFICATION MARK W 55-50 cx
2000 7, Id76 -
34 DMTR 25/100 IDENTIFICATION MARK W 54.00 * (.Y X,0(? ;\I/< CO.VIl. - 7 ,976
34 DMTR 25/150 IDENTIFICATION MARK W 54-50 * c-i 2000 /t/K LO\‘,). 7 ,976 -
DESCRIPTION
- Dual choke ,, compound /) type, anti-pollution carburettor with mechonicaliy controlled second choke butterfly
- Mechanically controlled acceleration pump ( cam ) on 1st choke
- Choke on 1st body vacuum assisted cold
start strangler flap
- Fitted damper on idling speed system.
* with incorporated fast idle device
ADJUSTMENTS
DESCRIPTION Primary choke
Venturi bore
Main jets ( removable )
Air corrrction jets
Emulsion tubes
Idling jets [removable ) .._..
Air-bleed idling jets
Acceleration pump injector -high type ( weighted )
Econostot petrol jet ( in cover )
Econostat delaying orifice ( in cover .I
Ball-operated needle valve
Double float : Weights
Positive butterfly opening - Strangler flap fully closed
22 26
115 135
AD 1 ( 195 ) AD 2 ( 180 )
F 30 F 25
50 70
110 70
40
110
100
1 75 “It”
13 1 0.5 g
1.25 i 0.05 mm I
Secondary choke

Downloaded from www.Manualslib.com manuals search engine 2 OPERATION No MA. 142-00 :Cbaracteris/ics and special j~,attlr~s o/the carhrrre~~or
7 6
8 9
1 ) Acceleration pump injector
2 ) 1st choke petrol idling jet
3 ) 1st choke idling speed air jet
4 ) Air correction jet with emulsion tube
and 1st choke main jet
-(5 ) Air correction jet with emulsion tube
and 2nd choke main jet
-16 ) 2nd choke idling jet
-(7 ) 2nd choke idling speed air jet
1. Location of main adjustments on carburettor
( cover removed ) :
2. Adjustment of positive opening of 1st choke
butterfly (strangler flap fully closed ) :
Set strangler flap control lever ( 14 ) to
fully closed position.
Hold butterfly control lever ( 13 ) in closed
position so that stop (12) contacts edge of
lever ( 14 ).
Measure distance between the edge of the
first choke butterfly and the carburettor body.
This measurement must he :
a = 1.25? 0.05 mm
If not, adjust the positive opening distance of the
butterfly by means of adjusting stop ( 12 ). This
clearance should always he measured with ad-
justing stop lock-nut ( 11 ) fully tightened.
3. Adjustment of clearonce of strangler flap (13)
activated by vacuum capsule (10).
Actuate strangler flap control lever ( 14) and
maintain in fully closed position.
Fit VCICUUII~ gouge on V~CUUIII capsule ( 10 ).
With minimum v(~cu”m depression of 400 mm of Hq
the thrust lever (8 ) should come into contact with
stop (9 ). If not, replace YClCUUrn capsule ( 10 ).
With these setti”gs,meosureme”t (G a aa taken
between the edge of the strangler flap and the
bore must
be between 3.25 and 3.75 mm.
If not, adjust stop screw (3).