1988 CITROEN CX Service Manual

REMOVING AND REFlTTlNG A FRONT
WHEEL HUB
REMOVAL
Support the front of the vehicle on stands
Take off the road wheel.
Withdraw, Fig. I
- the pin,
- the nut lock,
- the 35 mm A/F nut.
Lock the hub with tool 6310-T.
Remove the brake disc fas stated in chapter 0, op.
MA 45 1. l/3/.
Extract the swivel lower ball-joint nut
Uncouple the swivel lower ball-joint, Fig. II, using
either puller 3312-T or puller 6323-T (be careful
not to damage the ball-joint protection rubber).
Liberate the drive-shaft.
Take out, Fig. Ill :
- the screws,
- the hub. REFITTING
Introduce the wheel hub into the swivel.
Position the screws previously fitted with lugged
contact washers, Fig. Ill. Tighten to 2.7 mdaN.
Insert the drive-shaft end into the wheel hub (grease
the seal contact face).
Couple up the lower ball-joint.
Tighten the new NYSLTOP nut to 6 mdaN. (Wipe
the ball-joint fixing and recess, do not use solvent).
Refit the brake disc (Refer to @ MA 451. l/31.
Relocate, Fig. IV :
- the nut, use tool 6310-T to hold the hub in posi-
tion, tighten to 37.5 mdaN,
- the nut lock,
- the pin.
Bleed the front brakes
(See @ MA 453.0/l).
Reassemble the road wheel.
Lower the vehicle to the ground.

8531-8532

02.827 1
II
8531-8532

@I
SOURCE AND RESERVE MA ,,
OF PRESSURE
390.000/l
WORKING ON THE HYDRAULIC SYSTEM
\>
8531-8532

REPAIR OF THE HYDRAULIC SYSTEM
FITTING PRECAUTIONS
PRECAUTIONS TO BE TAKEN WHEN WORKING ON
THE HYDRAULIC UNITS OR THE SYSTEM
The correct functioning of the entire system presupposes perfect cleanliness of the fluid and the hydraulic
units. Stringent precaut!ons must therefore be taken when working on the hydraulic system and during the
storage of the fluid and components. 1. HYDRAULIC FLUID:
Mineral hydraulic fluid (LHM) is the only suitable type and must be used to the exclusion of all others in the hydrau-
lic system of the car.
This LHM fluid is green in co/our and similar to engine oil.
The use of any other would ruin the rubber rings and seals in the system. 2. RUBBER UNITS AND PARTS:
Suitable components are identified by their green co/our and may only be replaced by genuine replacement
components painted or marked in green.
All rubber components (seals, hoses, diaphragm, etc...) are of a special quality for use with LHM fluid and are
identified by their white or green colour. 3. STORAGE:
Components must be stored, full of fluid and blanked off. Like the piping, they must be protected against shock
and the ingress of dust.
Rubber tubing and joints must be stored away from dust, air, light and heat.
LHM hydraulic fluid must be stored in its original containers carefully sealed. We advise the use of one litre (for
topping up) or five litre cans (for refilling) to avoid having to keep opened containers. 4. CHECKS BEFORE CARRYING OUT WORK:
Before-working on the hydraulic system in case of faulty operation, ensure the following:
a) That the controls or the mechanical linkages of the units or the group of hydraulic units involved are
not stiff in operation
I I
b) and that the HP circuit is under pressure, as follows:
With the engine at idling speed:
- Unscrew the pressure-release screw on the pressure regulator by one turn to one turn and a half: a sound
of leakage should be heard from the regulator.
- Retighten the release screw: cut-out must occur which results in a reduction in the running noise emitted
by the H.P. pump.
If not, check in the following sequence:
- that there is sufficient fluid in the reservoir,
- that the reservoir filter is clean and in good condition,
- that the H.P. pump is primed and there is no air leak on the suction side of the pump,
- that the release screw of the pressure regulator is correctly tightened,
- that sealing ball (2) is in position, (see Fig. I and II, page 5).

REPAIR OF THE HYDRAULIC SYSTEM
FITTING PRECAUTIONS
5. PRECAUTIONS TO BE TAKEN BEFORE WORKING ON THE HYDRAULIC SYSTEM:
a) Carrefully clean the aera of work, the unions and the unit to be removed
- Disconnect the lead from the negative terminal of the battery.
- Only use petrol or lead-free petrol cleaning.
b) Release the pressure in the circuits:
- Place the vehicle in the K/OW~~ position.
- Slacken the pressure regulator release screw (by one turn to one turn and a half, do not remove the screw:
the sealing ball (21, see Fig. I and II page 5, could get lost,
- Wait until the front of the car has reached the low position. 6. PRECAUTIONS TO BE TAKEN DURING REMOVAL.
a) Blank off the metal pipes with plugs, and rubber tubes with round pins of the correct diameter
b) Blank off the openings of components with plugs of the correct diameter.
NOTE: Plugs and pins must be carefully cleaned before insertion 7. CHECK OR TEST OF HYDRAULIC UNITS:
- use 4034-T test bench equipped and designed for use with LHM fluid.
- This bench is painted green and its accessories are marked in green.
- Never use the bench with another fluid or for testing components operating with another fluid (units of a c(D))
car using LHS 2 for instance).
NOTE: The uLe Bozec)) pump used on test benches for checking DIESEL injectors can be resorted to for testing,
components operating with LHM mineral fluid provided that the bench is cleaned first. 8. PRECAUTIONS TO BE TAKEN DURING REFITTING.
a 1 Cleaning:
- steel pipes must be blown through with compressed air,
- rubber tubes and seals must be washed in petrol or lead-free petrol and then dried with compressed air,
- hydraulic units must also be cleaned with petrol or lead-free petrol and blown through with compressed air.
NOTE: Renew all joints and seals during refitting
b) Lubrication.
- Follow the indications as stated in the operations in the Manual.
- Joints and internal parts must be lightly oiled before fitting (use mineral fluid LHM only).
- If parts in contact with hydraulic units have to be greased, use a mineral grease only (as employed for cardan
shafts or bearings). +#+
8531-8532

REPAIR OF THE HYDRAULIC SYSTEM
FITTING PRECAUTIONS
c) Fitting..
Only use joints of a quality compatible with LHM mineral fluid.
To connect a union, proceed as follows: Fig. Ill
0 Position sleeve-seal u a )) lightly coated with LHM fluid ; this sleeve must not reach the extremity of pipe c(b)).
l Centre the pipe in the housing by lining it up with the axis of the hole, avoiding all stress. (Ensure that the
end c l Start screwing in the union-nut by hand, slacken the unit fixings, if necessary, to make this operation easier.
l Tighten nut moderately: excessive force could cause a leak because of the deformation of the pipe.
Tightening torques:
3.5 mm dia. pipe
0.8 to 0.9 m.daN
4.5 dia. pipe
6.0 mm dia. pipe 0.9 to 1.1 m.daN
The design of the various seals ensures that their sealing action increases with fluid pressure. In the case of a
leak, check the tightening torque of the union-nut. If the leak does not stop, replace the sleeve-seal.
To connect a rubber tube, a rubber ring of suitable diameter has to be positioned between the tube and the hose clip.
9. CHECKS ON COMPLETITION OF WORK.
On completion of work on hydraulic units or the system itself, check the following:
a) The union for leaks.
b) The clearance between the pipes: pipes must not touch one another or any component, nor may any other
unit., whether fixed or movable, exert any stress on them.