DACIA SUPERNOVA 2004 Repair Manual

36
STEERING ASSEMBLY
36 - 7
I.
DIAGNOSTIC OPERATION
A. Incidents occurring at the deformable lower shaft of the steering column:
a) Vibrations and steering wheel clearance (I1, I2, I3);
b) Noises in steering system operation (I2, I3);
c) Heavily turning, blocking tendencies (I4)
B. Corrective measures which ar e i mperative to r esolve the defe cts:
Incident Incidents (failures) e stablished Correcti ve measures
code
I
1Clearance in one or both cardanic joints. Replace the assembled deformable lower shaft
I
2Clearan ce in the splinted assem bled area between Replace the assembl ed deformable
ass. intermediary shaft and ass. intermediary pipe. lower shaft
I
3Clearance between lower bushing and ass. Replace the assembl ed deformable
intermediary shaft. lower shaft
I
4T ough points of the cardanic joint, blocking Replace the assembl ed deformable
tendencies. lower shaft
TIGHTENING MOMENTS (daNm)
Attachm ent screws of lower shaft connection 1,4
213
D
EFORMABLE LOWER SHAFT
vnx.su

36
STEERING ASSEMBLY
36 - 8
DISMOUNTING
Disconnect the battery.
Mark the steering wheel position (straight line driving position).
Dismount the connection screw (1) between the deformable lower shaft and the steering
wheel shaft. Loosen the screws of the front left wheel.
Lift the vehicle by means of a two-column elevator.
Dismount the left front wheel.
Dismount the connection screw (2) between the deformable lower shaft and the gear shaft
of the steering box. Dismount the sealing gasket (3) from the cowl panel.
Extract the lower shaft.
ATTENTION !
It is forbidden the damaging of the lower shaft and of the connection parts from the
steering system (steering box gear, steering wheel shaft) when dismounting/remounting
the lower shaft.
REMOUNTING
Clean the steering box gear shaft and grease it with grease UM 185 Li2 or UM 180 Li2.
Perform the dismounting operations in the reverse order. Tighten the connection screws between
the lower shaft and the steering box gear shaft, consequently between the lower shaft and the
steering wheel shaft to the required moment of 1.4 daNm.
D
EFORMABLE LOWER SHAFT
vnx.su

36
STEERING ASSEMBLY
36 - 9
S
TEERING WHEEL POSITION ADJUSTMENT
The steering wheel adjustment on vertical, is performed as follows:
- control downwards the adjustment handle ( 3 ) placed under the steering wheel lower
casing.
-bring the steering wheel in the desired position and maintain it in this position
- control upwards the adjustment handle.
It is forbidden t o perform this adj ustment during driving.
1. Steering lower shaft
2. Lower bushing
3. Adjustment handle
4. Assembled steering support
5. Bearing
6. Lock for shaft
7. Steering wheel attachment nut
8. Steering upper shaft
vnx.su

MECHAN ICAL ELEMENTS CONTROL
37
BRAKE PUMP
BRAKE PUMP WITH PRESSURE DROP INDICATOR ( ICP ) INCLUDED
COMPONENTS
1. Assembled primary piston with gaskets
2. Assembled secondary piston with gaskets
3. Primary piston pin.
4. Secondary piston pin.
5. Primary piston return spring
6. Secondary piston return spring.
7. Purging screw
8. ICP transducer
A –A ICP assembly section
OPERATIONA. B RAKING
THE FRONT BRAKE CIRCUIT
The primary piston is controlled by the pushing rod. A part of the brake fluid under pressur e
will operate together with the spring on the secondary piston, and the other part of the brake flui d
shall penetrate through the ducts to the upper floor towards both exits leading to the front brak e
calipers.
THE REAR BRAKE CIRCUIT
The secondary piston is continuing its movement, conducting the brake fluid under pressure ,
through the ducts, to the upper floor, towards the exit to the pressure-reducing valve. During al l
this time, the linings-pistons assembly will be balanced due to the two side springs .
37 - 1
vnx.su

MECHAN ICAL ELEMENTS CONTROL
37
B. DE-BRAKING
After effort ending, the two pistons resume their initial position under the effect of the retainer
springs, while the fluid is coming back and the pressure is decreasing in both circuits.
PRIMARY CIRCUIT – PRESSURE LOOSING
Lack of pressure in the primary circuit leads to the following situation :
The primary piston is a dvancing up to the pin, so is controlling mechanically the secondary
piston. The secondary piston reaches a fluid pressure that shall operate on the piston – linings
assembly moving it t o the right, opening also t he second e xit of t he rear circ uit ( the by-pass
circuit) increasing the pressure for this circuit. In this moment, by means of the transducer, the warning light on the instrument panel is on.
SECONDARY CIRCUIT – PRESSURE LOOSING
Both pump pistons go on. The caliper cylinders of the front brake shall normally operate.
The secondary piston re aches its respective pi n, but the pre ssure will decrease (due to the
failure). BRAKE PUMP
37 - 2
vnx.su

MECHAN ICAL ELEMENTS CONTROL
37
BRAKE PUMP
Close the connection pipe between the brake fluid reservoir and clutch transmitter cylinder
by means of the MOT 453 device. Disconnect the battery.
Drain the brake fluid reservoir.
Disconnect the connection pipe between the brake fluid reservoir and clutch transmitter
cylinder.
Dismount the brake fluid reservoir off the brake pump (avoiding fluid leakage).
Dismou nt :
- the rigid pipe screws from the brake pump and mark their position;
- the two attachment nuts of the brake pump on the servobrake .
DISMOUNTING
37 - 3
TIGHTENING MOMENTS (daNm)
Rigid pipe connection 1,5
Nut attachment P.C. with servobrake 1,3
I.C.P. (pressure drop indicator) 2
vnx.su

MECHAN ICAL ELEMENTS CONTROL
37
BRAKE PUMP
REMOUNTING
Perform the dismounting operations in reverse order.
Check the length of the pushing rod , value X = 9 mm and correct if necessary.
Before remounting, check the servobrake pushing rod stroke ( min.30 mm ).
After assemblin g the brake with the fluid reservoir and filling with brake fluid, no leakage must
occur in the surface of separation between the two elements.
IMPORTANT
The I.C.P. transducer is mounted after t he braking system purging.
ICP sub-assembly is not reparable ( ICP – pressure-decreasing indicator)
37 - 4
vnx.su

MECHAN ICAL ELEMENTS CONTROL
37
BRAKE PUMP REPAIRING
The operation is performed after dismounting the central pump off the vehicle.
DISMOUNTING
Dismount the brake fluid reservoir, recover-
ing the two sealing gaskets of the brake fluid res-
ervoir. Dismount the transducer and the purging
screw. Clamp a 3,5 mm drill in the vice.
Introduce the drill in the elastic pin
Rotate and draw the pump until the pin is ex-
tracted;
Extract the secondary piston elastic pin, in the
same way. Remove from the pump:
-the Pp primary piston assembled ;
- the primary piston return spring;
- the Ps secondary piston assembled;
- the secondary piston return spring
Wa sh the part s with alcohol and bl ow them
with compressed air. Check:
-the pump bore
- the pistons gaskets
- the springs
The parts of the “ primary piston” Pp and those of the “ secondary piston” Ps, cannot be repaired.
In case one of these parts is damaged, replace the whole kit ” primary piston” and “secondary
piston”, primary piston return spring, secondary piston return spring.
REMOUNTING
Before remounting, the parts and the pump bore will be lubricated with brake fluid.
Mount the “ secondary piston” and “primary piston “ assembly .
Compress the pistons and introduce the elastic pins; the pins slot shall be oriented towards the
pump attachmen t flange.
Mount the purging screw;
P urge the brake circuit and remount the ICP transducer. BRAKE PUMP
37 - 5
vnx.su

MECHAN ICAL ELEMENTS CONTROL
37
MASTER VAC 7 SERVO M ECHANISM
The ” Master-Vac 7” servobrake is a brake booster with the objective of reducing the driver
effort on the brake pedal.
AT TENT ION
The servobrake cannot be repaired.
The only items of the servobrake which are to be replaced are the air filter and the retainer
valve.
DISMOUNTING
Close the pipe between the brake fluid reservoir and the clutch transmitter cylinder by means
of the MOT 453 device.
Drain the liquid out of the reservoir.
Disconnect from the reservoir the feeding pipe of the clutch transmitter cylinder. SERVOBRAKE
OBSERVAT ION
In case one circuit is damaged, the pedal stroke shall be longer, the braking being
done only by the circuit still working.
37 - 6
T I GHTENING MOME NTS (daNm)
Brake pump nut on servobrake 1,3
Servobrake attachment nut on the cowl panel 2,0
vnx.su

MECHAN ICAL ELEMENTS CONTROL
37
REMOUNTING
Before remounting, check:-the a djustment of the main cylinder
stroke, which is obtained by acting on the pushing
rod nut in order to obtain value X= 9mm,
between the pushing rod end and the rest surface
of the main cylinder.
-the adjustment of the coupling fork on
the brake pedal side, which is obtained by
unscrewing the lock nut E and by acting on the
coupling fork i n order to obt ain the value L =
1 17 + 0,5 mm.
Fo r remounting, perform the dismounting
operations in the reverse order.
Purge the brake circuit.
Mounting the I.C.P. transducer.
Mount the electric connector at the I.C.P.
Detach the four rigid brake ducts from the
main brake pump. Disconnect the electrical contact from ICP
transducer. Dism ount t he m ain pum p fr om t he
ser vobrake.
Disconnec t the suction hose off t he
ser vobrake. SERVOBRAKE
37 - 7
Dismou
nt :
- the connecting shaft ( 1 ) between the
coupling fork and the pedal ;
-the attachment nuts of the servobrake
on the cowl panel.
Dismount the servobrake .
vnx.su