Dacia SuperNova (engine E7J). Manual - part 63

30

GENERAL

30 - 15

BRAKING CIRCUIT PURGING

PROCEDURE IN PARALLEL SYSTEM

1.,6. Main cylinder with I.C.P. incorporated
2. Left rear wheel  brake cylinder
3. Right rear wheel  brake cylinder
4. Caliper of front right wheel
5. Caliper of front left wheel

WORKING CONDITIONS

The vehicle is on wheels.
If the fuel tank is empty, place on the rear bench of the vehicle one or two persons to

enable the possibility of the circuit opening (the passing of a larger fluid flow through the
brake limiter).

CHECKING THE BRAKE SYSTEM SEALING

After purging the front and rear circuits, check if the level of brake fluid in reservoir is

within the minim and maxim range, than press the brake pedal, then during about 30
seconds, no pedal displacement must be noticed.

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GENERAL

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THE INFLUENCE OF THE FRONT AXLE ANGLES ON THE ROAD
BEHAVIOR  (VEHICLE COMPORTMENT) AND ON TYRES WEAR

CAMBER ANGLE 0

0

 +/- 30’

It is formed by the wheel plane with the vertical that crosses the wheel axis.
A difference higher that 1° between the two angles leads to :

- the deviation from the trajectory that must be adjusted by means of the steering wheel.
- abnormal wear of the tires and bearings.

The angle is not adjustable.

THE BALL JOINT ANGLE  12

0

45’ +/- 30’

It is formed in transversal plane between the axe connecting the attachment point of the

shock absorber with the ball joint center and the vertical passing through the wheel axis.
The ball joint angle is generating a negative offset, allowing the maintaining of the vehicle
route when the braking is unequal distributed.

The angle is not adjustable.

THE CASTER ANGLE  2

0

30’

It is formed in longitudinal plane, between the axis connecting the attachment point of the shock

absorber with the suspension ball joint center and the vertical axis passing through the wheel axis.

A difference higher than 1° between the two angles leads to :

- the deviation from the trajectory that must be adjusted by means of the steering wheel.
- a normal wear of the tires.

The angle is not adjustable.

STEERING BOX POSITIONING

The steering box must be at a certain height from the attachment points of the steering auxiliary

connecting rod ball joints. The position of the steering box (choking) is influencing the variation
of the parallelism. The steering box is mounted in the position for which the variation is minimal.

The modification of the parallelism between left side and right side leads to:

- the deviation of the vehicle, in one sense, upon accelerating;
- the deviation of the vehicle in the opposite side upon braking.
- the deviation of the trajectory on the hilly ground;
- the premature wear of the tires.

The horizontally of the steering box is ensured by the producer.

PARALLELISM

( TOE-IN OR ANGULAR SPREAD ANGLE )

It is measured in horizontal plane as a difference between the front and rear part of the same axle wheels.

The wheels are divergent. The value of the opening is between 0 – 2 mm (1 +/- 1 mm).

ATTENTION:
A too much opening causes the wear of the tires on the inner part of the camelback.
A too much closing causes the wear of the tires on the exterior part of the camelback.

The parallelism is adjustable by rotating the tie bar of the steering connecting rod.

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GENERAL

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PRELIMINARY CHECKING

Before checking and  adjustment of  the front axle geometry, perform the followings

operations:

* The checking of tires concerning:

- dimensions
- air pressure
- the state of wear;

NOTE  :
The tires must be of same type, with the same state of wear, air pressured at the

prescribed pressure.

*The check of joints:

- the wear of elastic bushings
- the steering ball joints clearance
- the wheels bearings clearance.

NOTE  :
The axial clearance of the bearings must be in admissible limits.

ESTABLISHING OF THE STEERING CENTRAL POINT

In order to perform a front axle checking and adjustment, it is necessary to establish the

central point in order to avoid measurement errors.
 To do that, bring the steering wheel so that device DIR 500 for steering box rack
blocking is entering in the orifice placed at its right upper part.

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GENERAL

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PRELIMINARY CHECKING

Due to the geometric conception of the front axle, the modification of one of one-

side angles (castor, camber, ball joint) has no major impact on the value of other side
angles (the parallelism being the one directly influenced).

The modification of these angles does not occur during vehicle exploitation, but only as

a consequence of a vehicle accident.

It is important to observe the following sequence :

- placing the vehicle on rotating plates;
- braked vehicle
- suspension checking for placing the vehicle at its free height;
- establishing the steering central point and steering box blocking.
- attachment of the optical devices on the vehicle, observing the manufacturer

instructions.

REPARTITION CHECKING AND ADJUSTMENT

Check the “X” dimension symmetry of

the connecting rods.

Reading of  the “A” value on the scale.