1981 Citroen CX hydraulic

Downloaded from www.Manualslib.com manuals search engine HYDRAULIC SYSTEM SUP.PLY DIAGRAMS
Source of pressure
I
h-Front suspension
Safety “‘lve ; Rear suspension
I
I Brake valve
i :ure limiter-
1
Front brakes Rear brakes
Source of pressure
I
Brake cccumulator
Supply to
I-way wion - steering governor
/Front
Safety va1ve- Rear suspension
I
Steering ( supply to slide-valve and operating cylinder )

Downloaded from www.Manualslib.com manuals search engine OPERATION No MA. 390-00 : (.hnrncteristics a?zd special fc~atuws oj the SOIUCC
arld ~~~scrm~ o]~prc’ss~~rc - Hydraulic systrm
2. Aisembly diagram : Op. MA. 390-00 13

Downloaded from www.Manualslib.com manuals search engine OPERATION No MA. 390-O : ChrckinR thr bydraalir co’mponcnts on the u&i& f Manual stcprine r~ebidos t Op. MA. 390.0 1
CHECKING’THE HYDRAULIC COMPONENTS
NECESSARY EQUIPMENT
- 1 pressure gauge A,
0 - 250 bars ( 0 to 3650 psi )
_ 1 3-way union B (No 5 416 494 K 1
- 1 pipeC (DX 394-185 ) ..
- 1 plug D ( 2 female ends 4 1.25 and 6 9 X1.25) = =
- 3 plugs E (mole ends : r$ 8 X 1.25 ) =
- 1 plug F (
mole 4 = 9 x 1.25 1
NOTE
: Plugs D, E md F are part 01 fhe kit
sold snder number 3657-T.
PREPARATION 1.
First ensure :
- that hydraulic reservoir filter is clean.
- that hydraulic fluid is ot normal running tempe-
rature ( Carry 0~1 a road lent first i/ vt4icie
is
mid ). 8 2. Draining the circuits :
Place manual height control lever in ion, posirios,
Slacken pressure regulator bleed screw ( 1 ). 3. Fitting pressure gouge A :
Disconnect the tube (2) HP outlet from pressure
regulator.
Connect the following assembly into the circuit :
pressure gaoge A, 3way union B and pipe C
between pipe ( 2) and the pressure regulator.
This ass~nzhly mrtst remain in positioa /brougbo~~l
the test. IMPORTANT :
The testing kquance described below must be
followed.
If after the test, a component appears defective,
either replace it or repair it before proceeding
to the next test.

Downloaded from www.Manualslib.com manuals search engine OPERATION No MA. 390-O : Checkin
P the hydraulic componm~s on the ucbicle Op. MA. 390-O 3
f Mama sleeting wbi&s I
6. Checking the safety valve :
=I
bl
Cl
dl
Remove safety v&e fixing screw ( 1 ).
Remove from safety valve :
supply pipe for front suspension (2 ),
- supply pipe for rem suspension (3):
Plug openings of safety valve ( pIugs E J.
Tighten pressure regulator bleed screw
and
start engine.
Disconnect rubher overflow return pipe and
watch aperture ~a>> of safety valve.
- I/ Iherr is a slight c7moa,,t 0, sHymge thr
sa/cty ~dve is s in good ordrv n.
el
-If thrr~ is a discharge of fluid the sniw
dw must be rqlacrd..
f ) Slacken pressure regulator bleed screw-
Conned overflow return pipe to safety valve.
Secure safety valve ( screw (( 1 a) 1.
7. Checking the safety valve slidevolve :
a) Remove plug from rem suspension outlet on
safety v&e at G b >a.
b ) Disconnect contact breaker lead on coil and
turn engine using stmter : fluid should start
to run through the opening a d N when pressure
reaches
1lLl +o 130 bars ( 1585 to 1885 psi )
c) Slacken pressure regulator bleed screw.
Connect contact breaker lead.
d ) Plug safety valve opening u b )) (plug E ).
8. Checking the hydraulic brake contml :
m ) Tighten pressure regulator bleed screw.
b) Start up engine.
When cut-out takes place wait a fen: seconds
for the pressure to stobilize.
Stop engine%
Watch pressure gauge and note the pressure
drop in the next 3
minutes. If pressure drop
exceeds 10 bors*( 145 psi ) repeat the test.
If the re< is the same. the broke control
valve is defective : change it.

Downloaded from www.Manualslib.com manuals search engine 9. Checking pressure switch (1) : Test procedure is the sctme as for checking
broke control.
Turn engine to obtain cut-out pressure.
Stop engine.
Operate brake pedal until the hydraulic pressure
warning lamp remains on.
Attbat point, read off pressure on pressure gauge.
This should be between 75
and 95 bars ( 1088 ta.
1378 psi 1, inclusive.
If not, change the pressure switch.
10. Checking the Front suspension : Slacken.pressure regulator bleed screw.
Remove plug E and connect front suspension
supply pipe (2 ) to safety valve.
Tighten pressure regulator bleed screw.
Start engine.
Put manual height control in
rronnaf rtmni>rp positim. Wait until the front end of vehicle rises and cut-
out takes place.
Allow pressure to stabilize.
Stop engine.
Examine pressure gauge and note pressure drop
during wperiod of 3
minutes. If it exceeds 10 bars
( 145 psi 1, check once more.
If the result is confirmed check the following
c?mponenG to determine which one is leaking :
either the front corrector
or the suspension cylinders (one or both ).
Testing the 3 components should be carried out by
eliminating each one in turn.
(I) Testing the front height cmwclor : Loosen pressure regulator bleed saew.
Put manual control in
loin position. Disconnect supply pipe (3 ) for front cylinders
from 3-way union (4 ).
Plug tube (3 ) using plug D ( female 1.
Tighten pressure regulator bleed scwe.
Place manual height control in normal running
posiGon:Start engine.
Allow pressure to stabilize.
Stop engine.
Read off pressure drop on pressure qtruqe.
If this drop in pressure is greater than
10 bars (
145 psi ) during a period of 3 minutes, repeat
test. If the result is confirmed, the front height
corrector is defective : change it.
Remove plug and connect pipe (3 ) to 3roy
union
(4 ).

Downloaded from www.Manualslib.com manuals search engine a OPERATION N’ MA. 410-O : (./~rrkiq N,,I/ VI. CHECKING AND ADJUSTING THE STEERING GEOMETRY
The crossmember supporting the steering has slots at its fixing point on the front subframe.
Any vertical movement of this crossmember alters the steering geometry.
WARNING
This operation is only to
be carried out in certain ccxses such as
-accidental impact, with repercussions on the steering system.
-work on the vehicle entoiling removal of steering crossmember.
- vehicle with poor
road stability ( p oar stright-line stability) 01 with excessive tyre weor.
CHECKING
1, Prepare the vehicle. as for checking front wheel
alignment ( Srr ~ho/,lvr
V I.
NOTE
A ) \In,,unl ~fi~<,r;,,~ I chiclvs :
With the steering in the /< straightahead 1)
position. lock the steering using CI commercially
available tool ( FACOM _ MULLER -WILMONDA)
B) PO,, P)’ \,r,rr;ng r’cliirl<,.s :
Do not actuate steering wheel during check
( hydraulic locking of rock 1.
As a precaution. a steering wheel iocking
tool may also be
used. 2. Mark position of vehicle in relation to
ground :
Secure a weighted length of string to the front
bumper. and
mark the position of the weiqht on
the ground ( The
object of this is to always bring
the vehicle
bock to the some position in order to
carry out correct measurements 1.
NOTE Other procedure
This check having to be carried out wheel hy wheel.
it is possible to use the free projector.
Secure projector to scuttle panel crossmemher, and
focus it onto a fixed object, which will indicate the
initial positioning of the vehicle.
3. Measure the variation in the wheel alignment wheel
by wheel, ds o function of the height of the vehicle.
a) From Ihc m~nwnl rlri,:ir,g posi/ior, lo /hc hi@
posilio,, f ftouad 1 :
With vehicle in mwmal rlriving position.
engine running ond position marked in relation
to groond :
Mark position of luminous spot on front graduated
rule.
Place m’anual height control lever in hi&
posilirrrl.
and wait for vehicle to stabilize.
Check and adjust if necessary position of vehicle
in relation to ground. ( II
eight 01 Inmbrous spol
ou /i wd 0 hit,< I J.
Mark position of luminous spot on front graduated
rule. and on rear one
1) Front and rear readings ore the some (no
variation in alignment in the wheel 1.
NOTE : The reading f I,i$ or lorr posilios J
on the qroduated rules differs from the initial
reading f non,,nl >r,nrlinl:
position J because
the front track has altered.
2) Front and rear readings ore different ( in this
case the alignment has oltered,.either in
toe-in or toe-out ).
0 to 1 mm toe-in is permissible on either wheel
b) ,:rr ,,I, /bv IIDIINRI hi&g ,,osi,;orr lo ,I,<, lo,,
posiliov f Hrlmuad ) :
Proceed OS for previous measurements, place
manual height control lever in low position. In
this case. the permissible difference in oliqn-
ment
is O.to 1 mm toe-out.

Downloaded from www.Manualslib.com manuals search engine II. POWER STEERING WITH POWERED RETURN
I. CHARACTERISTICS
Hydraulically operated rack and pinion steering Steering
ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 13 5 i
- No of steering wheel turns from lock to lock
. . . . . . . .._._.__................................................ 25
- Turning circle (( between walls ))
11 80m
(.S x00 OIlCi ( s .2x0 solooll.~
(( between kerbs )) 10 90 m t
/( between walls )) 12 70 m
I( between kerbs 1) 11 80 m t I’\/N/l’ N/id I’n~\lix”
- Wheel alignment ( toe-in of wheels to the front i (i/l //I( //r~rjj/rll c/r;/ ii/:: p, cilirJ/i 1 1 to 4 mm
STEERING AND HYDRAULIC RACK CONTROL ASSEMBLY
1. Steering-wheel
2. Anti-theft device
3. Control unit
4. Steering shoft
5. Coupling flonge
6. Eccentric for odjusting stroight line running
7. Clomp for coupling hydraulic pipes
Jl J2 obtoined by moving clomp (5) olo
STEERING COLUMN, AND HYDRAULIC CONTROL UNIT

Downloaded from www.Manualslib.com manuals search engine THIS STEERING SYSTEM HAS THREE DIFFERENT FUNCTIONS
- Power operation i rc,d/ic-/ici// 0 I .~/I c,r-i/lg-o /Io.c,/ c’//or/ /
Stiffeninq of the steerinq as a function of the speed of the vehicle f s////it-ic,r/t /<,(,I o/ 11~1 c/c,c~ri/t.cq r/~llc(,I I//JNI(,I or
lhc, 1 cjhicle spc,c~d )
1. Steering pinion 5. Piston seal
2. Rack housing 6. Rack
3. Sleeve 7. Rack plunger
4. Piston
I SECTION THROUGH RACK AND HYDRAULIC RACK CONTROL UNIT ( OPERATING CYLINDER )
SECTION THROUGH HYDRAULIC RACK CONTROL UNIT ( OPERATING CYLINDER )
a) Hydraulic rack control unit ( operating cylinder )
The rack is connected to the hydraulic control unit ( operating cylinder )
Assume S as the piston in chamber 1, and S/ 2
its surface ( ns dcjsiguvd iu c-hmvhc 1’ 2 J.
The steering is balanced when forces F and Fl exerted on each face of the piston are equal
therefore F = S x F =Fl +x HP
HP 1 operatinq pressure of hydraulic circuit f mist s l‘ront /hc r-r/-iit /I,,( s.5~1’~~ lo fhc cf4I-r)ul /~r~~.~.s~ir~~ J.
Movement of the rack ( therefore, power operation ) is ensured by a change in pressure inside chamber 1, such
as
I Return of fluid to the tank -HP / 2 decreases
- Inlet of fluid -HP/ 2 increases