1976 Citroen CX water pump

Downloaded from www.Manualslib.com manuals search engine I. CHARACTERISTICS
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5 Cooling system : Water cooled.
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T cx 2000 cx 2200 CX 2400 and Prestige
CX 2400 GTI
- Type ( on engine p’late ) : _..._................... M 20/616 M 22/617 M 23/ 623
M 23/622
Cubic capacity : . . .._......_...............
1985 cc 2175 cc 2350 cc 2350 cc
Transversely mounted, inclined
300 towards the front
Number of cylinders : _........................... 4 (iI/ linr, J 4 Iin linr,)
4 (irr /iUP J 4 f in lin i’ ,
Bore : 86 mm 90 mm 93.5 mm 93.5 mm
- Stroke : .,.,,_,.,.,....____.,.. .._._.....................
85.5 mm 85.5 mm 85.5 mm
85.5 mm
Compression ratio :
9/I 9/l 8.7511 8.7511
Maximum power ( DIN ) : . . . .._................... 102 bhp at 5500 rpm 112 bhp at 5500 rpm 115 bhp ot 5500 rpm
128 bhp at 4800 rpm
Maximum torque (DIN)
: . . 15.5 m.kg (112 ft.Ib ) 17 m.kq (123 ft.Ib) 18.2 m.kg ( 132 ft.Ib)
20.1 mkq (145 ft.Ib)
at 3000 rpm at 3500 rpm at 3000 rpm
at 3600 rpm
Maximum engine rpm in 4th gear :
* 13/62 final drive rtrtio :
5600 rpm 5800 rpm 5900 rpm
*14/61 final drive ratio ( -1 1’175 J 4600 rpm
Maximum engine rpm in 5th gear
(
13,‘62 final drive ratio ) : ,._............,..,........,....,.,........,..,.,..... .._.........,................ .._..._...................
5600 rpm
* NOTE : For CX 2200 and CX 2400 vehicles fitted with a torque converter, the maximum rpm in 3rd gear is 5600 rpm.
: Lubrification :
i
Under pressure, supplied by o gear-type oil-pump driven by the camshaft.
2
External oil filter cartridge ( PURFLUX, LS 105 type ).
d
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i Fuel supply :
a
i a) Engines fitted u~ifh a rnrbuwffor
WEBER compound-type twin choke carburettor (s.ee Operations MA. 142-00, 142-00 a, 142-00 b far the type, and the identification marks )
Dry-type air filter, with filter cartridge.
Mechanical fuel pump, driven by on eccentric on the camshaft.
b) i?ugi,jes ji/f.rd II ith /LIP/ iniPr/ioo :
BOSCH L-Jetronic electronic fuel injection system
Grade of pet,ol to be used : > ._,,,,.,_.._,,,,,.,......... . .._...o....._............................................. K.
99 Orrani ralrrig (FRANCE : Super grade ) (U.K. : 4-star )
Ignition :
Distributor ( DUCELLIER or MARELLI ) driven by the camshaft.
NOTE : The M 23/622 engine with fuel injection is fitted with (I DUCELLIER distributor with a magnetic sensor, and an u AC-DELCO /a electronic module.
- Spark pluqs : .................................................................................................................................... shorf warh
Firing o&r : .................................................................................................................................... 1 - 3 - 4 - 2 f tbu cylinders ale INR&Cd 011 the roc6w COI rr,
Timing :
Side mounted camshaft located in crankcase.

Downloaded from www.Manualslib.com manuals search engine II. cx 2000
The object of the system is t3 reduce the amount of unburnt hydrocarbons and the amount of CO in the exhaust
( approximately 2 to 3
of CO ) by injectinq air under pressure into the exhaust manifold
OPERATION :
As the enqine rotates air pump ( 12) supplies the air injectors located near the exhaust valves: flap ( 13 )
prevents the exhaust fumes from entering the air pump and air supply duct assembly.
There are two cases where it is necessary to stop the injection of air into the exhaust manifold.
1. During deceleration :
Durinq fast deceleration. the mixture becomes richer combustion is incomplete and the injection of air is
stopped in order to avoid a second combustion takinq
place in the exhaust system ( which would result in
back-firinq ) Durinq deceleration there is extreme low pressure downstream of the butterfly ( 1 ). This in
turn draws in for a short period of time the diaphragm in valve ( 11 )
The air supplied by pump ( 12 ) is released into the atmosphere, the calibrated hole (( a 1) on the diaphragm
balances the pressure on either side of it and the diaphraqm returns to its initial position, allowinq air to
be once more injected into the exhaust manifold
2. With the choke out, for an engine coolant temperature of above 45’ + 3’ C, and whenever the coolant tempe-
rature remains above 35’ i “,I C.
In this situation the quantities of unburnt hydrocarbons and CO are very considerable It ‘is therefore necessary
to stop the injection of air into the exhaust manifold so as to avoid any excessive increase of temperature in
the manifold. On CX 2000 vehicles, injkction of air will be stopped when the enqine water temperature reaches
45” + 3- C Thermal switch ( 8 ) opens, relay ( 9 )
1s no lonqer enerqized. but electro-valve ( 7 ) remains live
( relay lead ). and is earthed via the choke control
The air pressure at the outlet of air-pump ( 12 )
increases the effect of the low pressure on the diaphraqm in
valve ( 11 ) ( the air pressure is felt above the diaphraq,m, and the low pressure produced by the carburettor (2)
is felt below the diaphraqm ). the slidinq valve in the duct chanqes position and the air is expelled into the
atmogphere If the choke ( 10) is pushed back in air is once again injected into the exhaust manifold
DEVICE FOR OPENING THE BUTTERFLY :
The object of the device is to maintain combustion during sudden deceleration up to an enqine speed
of
Nd 7 1800 + 100 rpm.
Durinq deceleration for any enqine speed above Nd, the electronic tachometer housinq ( 6 ) earths the
windinq of relay ( 5) Therefore the H PIERBURG 1) electro-valve ( 4) is no lonqer enerqized. Electro-
valve ( 4) is then under low-pressure, below the diaphragm of the device ( 3 ) for opening the butterfly
When the decreasinq enqine speed falls below
Nd, the electronic tachometer housing (6 ) cuts out the
earth of the winding in relay ( 5) Therefore the (( PIERBURG )) electro-valve ( 4) is enerqized The
electro-valve is no lonqer under low pressure below the diaphraqm of the device (3) for openinq the
butterfly the throttle butterfly returns to it s stop aqainst the idlinq speed adjustment screw. The dia-
phraqm of the device (3) for openinq the butterfly will once aqain be affected by low pressure ( under
the control of the electronic tachometer housing ) once the increasing engine speed reaches
NC ~ Nd t 50 to 250 rpm

Downloaded from www.Manualslib.com manuals search engine CHECKING THE SAFETY DEVICE FOR THE CHOKE
f (.X 2000 j :
1. Electrical components :
Disconnect the u blur )) lead feeding the thermal
switch (1) located on the water outlet duct on
the cylinder head.
Switch on the ignition.
Earth the lead from thermal switch ( 1) the relay ( 2 )
for the << WEBER 1) electro-valve ( 3) must operate.
Leave the thermal switch disconnected with the
lead insulated from earth.
Pull the
choke knob. electro-valve (3) is supplied
by relay (2 ) and is closed by earthing via the choke
control.
2. Pneumatic components :
Disconnect from the air-supply valve ( 5) the
pipe (4) from the valve to the exhaust manifold.
Plug the pipe in order to avoid the exhaust pressure
deteriorating the end of the tube and the valve
Use the starter to rotate the engine.
In this position. the air pump (6 j must
not supply
air through the previously disconnected opening in
the air supply valve ( 5)
CHECKING THE AIR INJECTION
Push back the choke
In this position. the air-pump (6 ) must supply air
through the previously disconnected opening in the
air-supply valve ( 5 1.
Accelerate the engine, and suddenly decelerate
The injection of air throuqh the opening must stop
for a short while.
Run the engine until the cooling fan ( or fans ) cut
in.
Pull the choke out : the air flow through the opening
in the air supply valve ( 5) must cease.
Push the choke in : the air flow must resume.
Connect to the air-supply valve ( 5) the pipe ( 4 )
from the valve to the exhaust manifold.

Downloaded from www.Manualslib.com manuals search engine Ill. CHECKING AND ADJUSTING
1
. Energizing the system ..................................................................................................................
2. ,Fuel pump feed ( on operating the starter ) .............................................................................
3. Fuel pump feed ( with engine running ) ...................................................................................
4. Supplementary air control ...........................................................................................................
5. Air-flow sensor ............................................................................................................................
6. Resistors and injectors ................................................................................................... . ........
7. Water temperature sensor ............................................................................................................ .
Dingram 7
8. Air temperature sensor ...............................................................................................................
9. Cold-start injector, and thermal switch ...................................................................................
10. Switch on throttle butterfly spindle ( idling speed function ) ............................................ 11
Switch on throttle butterfly spindle ( maximum power function ) ...................................... 12.
E.C.U: ......................................................................... ..~ ............................................................... . . Diagram 1 I ANNEXE : A
: Checking the ignition .................................................................................. Page 25 B
: Checking the air circuit ................................................................................ Page 26
C : Checking the fuel system and the fuel pressure ........................................... Page 27 D
: Adjusting the idling speed and the exhaust emission .............................. Page 28 NOTE
: On the wiring harness for the injectors, the numbers of the terminals on the E.C.U. terminal board are
visible on the rear section. after having withdrawn the casing secured by the end screw.

Downloaded from www.Manualslib.com manuals search engine 4 OPERATION No MA. 210-O : (hcrkir,p or, III. FITTING THE DISTRIBUTOR ONTO THE VEHICLE
1. Set the distributor to the static
advance point :
a 1 Bring piston of NC 1 cylinder to the static
advance point, as follows
Lift the L.H. front wheel of the vehicle ( L.H.
side of the vehicle jacked up ) and engage
4th gear.
Blank off the plug-hole with the palm of the hand.
Rotate the L.H. front wheel, and stop when the
palm of the hand is pushed back by the force of
the compression.
Slowly rotate the wheel to bring the 10”
morkabx
of the engine flywheel ( 1) opposite the fixed mark (c a aa.
b) Fit the distributor
Remove the distributor cap.
Insert the distributor into its housing ( see
position on the dioqram below 1.
-, water pump LONGITUDINAL AXIS OF ENGINE
--~-__ -- -- ----~--
Position of distributor arm before position-
ing distributor in its mounting
I
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Vacuum capsule
removed
capsule in place Position of arm after fitting distributor

Downloaded from www.Manualslib.com manuals search engine 4 OPERATION No MA. 210-O o : (./wrkh,i: rind nrlj,,s/inp /hc rlvr/,riai< igvi,io,, ~YS/C,,,,.
II;. FITTING THE DISTRIBUTOR ONTO THE VEHICLE
_ water pump
LONGITUDI 1 AL AXlS OF ENGINE
.-.-.-
distributor arm
Position of dist:ibutor arm befol
fitting distributor in its mountin 1. Set the distributor to the static advance curve :
a) Bring piston in N’ 1 cylinder to the static
advance point LTS follows
Lift the L H. front wheel of the vehicle
i ,..I,. .\;,I<~ o, / vhirl<~ in< kvd ,,/I, and engage
4th or 5th qeor.
Remove the spark plug from N’ 1 cylinder
Blank off the plug-hole (use a plug ).
Rotate the L H. front wheel and stop when the
plug is forced out by the compression.
Rotate wheel slowly to bring the 10, markiicai
on the flywheel ( 1 ) opposite fixed mark cs b >)
visible throuqh opening S< a ))
b 1 Fit the distributor
Remove the distributor cop: insert the distri-
butor into its housing ( see position in dioqrom
and photograph on this page ).
Provisionally position fixing clamp and
moderately tighten nut.
Position distributor cap and secure it.
Fit spark plug to N’ 1 cylinder. 2. Adiust distributor timing using either strobe
lamp or test-bench :
25” .a+ 2500 rpm I 7 “c,,,m nrli n,,ci’ rlicronsvr~d)
Tiqhten distributor clomp nut from 1.9 +o 2.1 daNm
( 13.5 to 15 ft.lb ).

Downloaded from www.Manualslib.com manuals search engine OPERATION No MA. 236.0 : C h<,rki,,p a,,d nd;r,slh,p I/w jwllr\s aurl /x,//s Op. MA. 2360 I
PULLEY ALIGN& IENT
1. Aligning the camshaft pulley :
a) Position device 3085-T on the water pump
pulley.
b) Bring its rod into contact with the groove of the
camshaft pulley.
NOTE Aligning the camshaft pulley is carried
out by’plocing shims behind the pulley.
Tightening torque for nut (2) for the comshoft
pulley : 8 daNm ( 58 h.lb ).
2. Aligning the alternator pulley :
Proceed as for camshaft pulley / ,,,;/I> s SC-r<,!, , j I /or I,,<, RllI~)11010F c<)L,, <,d i,, ,,
NOTE Aligning the alternator pulley is carried
out by plocinq shims behind the pulley.
Tightening torque for nut (4) for the olternatov
pulley : 4 daNm ( 29 ft.lb ).
3. Aligning the high pressure pump :
a ) Tighten pump on its support plate
b) Place device 3085-T on the camshaft pulley.
c) Brinq its rod into contact with the groove of the
pump pulley.
NOTE Aliqninq the H P pump is curried out using
adjustment shims placed between the pump housing
and the support plate.
Tightening torque for the nut securing the H.P. pump :
4 doNm ( 29 ft.lb ).
NOTE Vchirlc,s filled ,,~;//I oirrrii,rli/iriniii,~
For the alignment of the compressor pulley, SLO
Opr~mrio~, MA, ~,40.,-(,.

Downloaded from www.Manualslib.com manuals search engine 2
TENSION OF BELTS
RECOMMENDED TENSIONS f /or i//jormation I
Water pump belt :
New belt : ........................................... ................................................. 400 to 450 N ( 40 to 45 kg ) 88 to 99 lb
Run-in belt ...................................................................................... 250 to 300 N ( 25 to 30 kg ) 55 to 66 Ib
Alternator belt :
New belt ......................................................................................... 400 to 450 N ( 40 .to 45 kg ) 88 to 99 lb
Run-in belt .................................................................................. 250 to 300 N ( 25 to 30 kg ) 55 to 66 Ib
Vchicic)s with power slcvring :
H.P. pump belt :’
New belt ........................................................................................... 350 to 400 N ( 35 to 40 kg ) 77 to 88 lb
Run-in belt ............................................................................... 200 to 225 N ( 20 to 22.5 kg ) 44 to 50 lb
Compressor belt :
New belt ......................................................................... ............... 400 to 450 N ( 40 to 45 kg ) 88 to 99 lb
Run-in belt 2% N
..................................................................................
( 25 kg 1 55 Ib
Toothed belt for water pump : ........................................................ 150to180N( 15to18kg)33to40lb
NOTE : Insufficient tension reduces considerably the reliability of the toothed belt.
Tension in excess of 180 N ( 18 kg ) ( 40 Ib ) will cause whistling noises.
Consequently. adjust toothed belt tension as tight as possible without it whistling tighten until it whistles whilst
running. and slacken until the noise disappears.