Dacia SuperNova (engine E7J). Service manual - part 62

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GENERAL

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BRAKING SYSTEM DIAGNOSTIC

II. 

CONSTANT EFFECT  AT  BEHAVIOUR

EFFECTS

Brakes not accomplishing the
required braking distance

Vibrating brakes

When braking, the vehicle ( front
part) is left/right deviating

Braking

Heating brakes

POSSIBLE CAUSES

-  Non-un iform worn b rake  lin ings
(backing off);
- Brake linings slightly greased;
- Springs with modified characteristics.

- Brake disks with high wobbling;
- Inconstancy brake disks width;
- Particles abnormal deposit on brake disks
(oxidation between linings and disk).

-  Front axle suspension, steering (to be
checked);
- Stuck piston;
- Tires – wear, inflation pressure;
- Rigid duct narrowed (flattening).

- Stuck piston;
Automatic adjustment : hand brake cable very
tighten.
    REMARK :
       Automatic recovering is performed by
means of the brake pedal, if there is no ab-
normal tension in the hand brake cable
when released (hand brake released).
- Return spring.

- Insufficient hydraulic stroke of the brake
pump, not allowing the return at rest of
the brake pump pistons ( brake pump
remaining under pressure);
- Stuck pistons or hardly returning;
- Rigid duct narrowed (flattening);
- Defective adjustment of the hand brake
control.

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GENERAL

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BRAKE CONNECTIONS AND SEWERAGE

The sewerage connection between the brake pump, brake calipers, pressure limiter is

performed by means of the threaded connections with METRIC PITCH.Therefore it is
important to use only original spare parts, recommended in the Spare Parts Catalogue,
specific for this type of vehicle.

Spare parts identification

The cupping shape of the steel ducts  (A)

The shape of the threaded lengths on

parts (B)

Connections of ducts  (C)

A

B

C

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GENERAL

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BRAKE FLUID

PERIODICITY OF THE BREAK FLUID CHANGE

The manufacturing conception of the brakes equipping the Dacia vehicles, especially

the disks brake type (F 54 inner empty pistons, low quantity of fluid in the cylinders,
sliding calipers avoiding existence of a fluid reserve in the less cooled area of the wheel)
enable the maximum rejection of fluid vaporization risk, even in case of intensive using of
brakes (mountain area).

The current brake fluids are subject in all cases to a slight degradation during the first

months of use by a slight humidity absorption series (see the Vehicle Warranty and
Maintenance Booklet, for brake fluid change)

LEVEL COMPLETION

The wear of brakes pads and shoes generate a gradually diminution of brake fluid level

in its reservoir. It is useless to compensate this diminution, because the level will be re-
stored in the moment of next changing the brake pads and shoes. Obviously, in the mean-
time, the level of brake fluid in reservoir must not go down bellow the minimal mark.

HOMOLOGATED BRAKE FLUIDS

The mixture in the braking circuit of two non compatible brake fluids may leads to loss

important risks mainly due to gasket damage

In order to avoid such risks, it is obligatory to use brake fluids checked and approved by

our laboratories and which are according to Norm SAEJ 1703, DOT 4.

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GENERAL

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BRAKING CIRCUIT PURGING

AIR ELIMINATION FROM THE HYDRAULIC

CIRCUIT (PURGING)

The air existence in the hydraulic circuit may be noticed by an elastic displacement of

the brake pedal, sometimes even, close to the floor. This fact is more evident with the
engine stopped.

GENERAL RECOMMENDATIONS

Always use for completion or total changing, the brake fluid Norm SAE J 1703 , DOT 4.
In case of changing the brake fluid, it is necessary to wash the system with one liter of

industrial alcohol (diluted).

 During the purging, the brake fluid from the reservoir must not go down bellow the

minimal level marked on the reservoir.

To perform the operation, one person will stay on the driver place, to push the brake

pedal and the other one will perform the purging (bleeding) at the wheels using a 500 ml
vessel, a transparent plastic tube and brake fluid for completion.

NOTE 
The brake fluid resulted  after performing the  purging operation, IS NOT TO BE

RE-USED but only after 48 hours, in order to avoid air-bubbling generation on the
hydraulic circuit which shall have as effect an elastic brake pedal.

WORKING PROCEDURE

Place on the purging screw, a transparent tube with its end in a vessel with brake fluid

and proceed as follows:

- press the brake pedal slowly, dismount the purging screw, maintaining the full

stroke of the pedal, then tighten the screw and slowly release the brake pedal. Repeat the
same procedure until complete cease of air bubbles. Proceed in the same way also for the
other purging places.(take into consideration the existence all the time of the brake fluid in
the reservoir)

Observation:
Before beginning the purging procedure, dismount the I.C.P. indicator from the pump,

which shall be remounted at the end of the operation.

It is important to observe the following sequence of the purging places: