2004 DACIA SUPERNOVA brake fluid

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)
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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
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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.
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T I GHTENING MOME NTS (daNm)
Brake pump nut on servobrake 1,3
Servobrake attachment nut on the cowl panel 2,0
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MECHAN ICAL ELEMENTS CONTROL
37
BRAKE PRESSURE CONTROLLER
Brake pressure controller, load sensitive, avoiding the rear wheels blocking.
OPERATION PRINCIPLE
The brake pressure controller enables the rear circuit pressure “ modulation “ according to
two parameters:
-the pressure value in the front circuit
- the load on the rear axle
The pressure controller is operating on the principle of pressure compensation in two enclosures,
separated by means of a ball and spring valve. The back pressure at the valve level is created by means of the forc e developed by the
continuos action compensating spring and of the control spring acting in proportion as the rear
axle load is increasing. The pushing rod is transmitting the force of the lever spring to the pressure controller piston,
which is controlling the valve ball being in the open normal position (position P 1).
BRAKING MOMENT
In the same time with pressure increase when entering in the pressure controller, this will act
upon the ball, forcing it to overcome the c ontinuos acting spring force and by uncovering the
valve hole, to facilitate the releasing of this pressure. In the braking moment, due to position
changing of the vehicle body compared to the rear axle, by means of the acting levers, the limiting
piston is moving toward the interior, reducing the fluid exist diameter, leading to the obtaining in
this way of the pressure reduction in the rear circuit.
DE BRAKING MOMENT
In the moment of fluid inlet pressure restoring ( by leg lifting from the brake pedal ), the piston
will come back in the initial position, gradually and quickly allowing the same diameter existent at
the beginning of the braking for which the valve is open ( position P1 ). 1.
Pressure controller body
2. Valve
3. Plug
4. Spring
5. Ball
6. Piston
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MECHAN ICAL ELEMENTS CONTROL
37
BRAKE PRESSURE CONTROLLER
NOTE
The brake pressure controller is not to be repaired.
DISMOUNTING
Drain the circuit, recover the fluid;
Detach the four connections (1) of the rigid pipes.
Dismount the two M6 attachment screws of the pressure controller support on the floor (2).
Remove the support together with the pressure controller from the fixing clips.
Dismount the pressure controller off the support.
REMOUNTING
Mount the pressure controller attachment screws on the support.
Attach the support-pressure controller assembly on the floor.
Mount : -control lever
- the four connection screws of the brake pipes
Purge the braking circuit and adjust the pressure controller.
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TIGHTENING MOMENTS (daNm)
Pressure controller attachment screws on support 0,58 daNm
Pipe tightening connection screws to the pressure controller 1,5 daNm
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The working principle of this control is similar to the one of a brake control, having the same
wo rking fluid : SA E J 1703 DOT 4.
TRANSMITTER CYLINDER REPLACEMENT
DISMOUNTING
Disconnect the battery.
Drain the clutch control hydraulic circuit ; for this purpose, open the purging connection and
connect to this a transparent hose for draining. Dismou nt :
- dashboard lower pa rt ;
- the feeding pipe 1 with brake fluid from the reservoir;
- the hydraulic pipe of the transmitter cylinder 2.
Detach the cylinder rod from the control pedal bolt (dismounting effort : min 5 daNm ).
Di smount the transmitter cylinder 3 as follows: by means of 24 mm wrench, rotate the
transmitter cylinder from the right to the left aprox. 45 ° and extract the cylinder ( dismounting
moment : min 0.2 daNm ).
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CLUTCH HYDRAULIC CONTROL
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MECHAN ICAL ELEMENTS CONTROL
37CLUTCH HYDRAULIC CONTROL
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REMOUNTING
Perform the dismounting
operations in the reverse order ;
-tr ansmitter cylinder mounting moment on the support – max 0.5 daNm
- cylinder rod mounting moment on the pedal bolt – max. 5.0 daN
Refill the brake fluid reservoir and purge the clutch control circuit by means of the purging
connection. Adjust the level in the brake fluid reservoir.
At t ent i on
When remounting the feeding pipe at the brake fluid reservoir and at the
transmitter cylinder, observe the positioning markings.
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MECHAN ICAL ELEMENTS CONTROL
37
HYDRAULIC RECEIVER REPLACEMENT
This operation shall be performed after dismounting of the engine-gearbox assembly and after
disconnecting of the engine from the gearbox.
DISM OUNTING
Dismount the two attachment screws and dismount the hydraulic receiver.
REMOUNTING
Perform the dismounting operations in the reverse order.
Tighten the screws at the required moment of 2.1 daNm.
PHYDRAULIC CIRCUIT PURGING
1. CIRCUIT REFILLING
Check if the clutch pedal is in the “up” position, maintain it by hand if necessary.
Fill the reservoir with brake fluid.
Remove the protection cap of the purging connection 1.
Connect a transparent hose a t the purging connection to recover the brake fluid.
Retrieve the clip 2 (do not definitely remove it in order to limit the movement of the feeding
pipe).
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CLUTCH HYDRAULIC CONTROL
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