Braking Circuit Purging - Dacia 1304 2004 Repair Manual

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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.
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.
During the purging, the brake fluid from the tank must not go down bellow the
minimal level marked on the tank.
To perform the purging, one person will stay on the driver place, to push the brake
pedal and the other one will perform the purging (bleeding) at the wheel using a 500 ml
vessel, a transparent plastic tube and brake fluid for completion.
Place on the bleeding (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 bleeding
screw, maintaini n g the full stroke of the pedal, then tighten the bleeding screw and slowly
release the brake pedal.
Repeat the same procedure until complete cease of 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 tank ).
ATTENTION : Before beginning the purging procedure dismount the I.C.P. from
the brake pump. It shall be remounted at the end of the operation.
It is important to observe the following sequence of the purging points:
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.
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).
After purging the front and rear circuits, check if the level of brake fluid in tank is
within the prescribed limits, than press the brake pedal for 30 s ,during this time the pedal
shall not change its place.
Leaking in the brake system is not acceptable.
GENERAL

BRAKING CIRCUIT PURGING

G
ENERAL RECOMMENDATIONS
P
ROCEDURE
P
ROCEDURE IN PARALLEL SYSTEM
O
PERATING CONDITIONS
C
HECKING THE BRAKE SYSTEM SEALING
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