Skoda Felicia

since 1994 release

Repair and operation of the car

Pumping of hydraulic system

Hydraulic liquid is highly toxic substance - try not to allow hits it on open sites of skin and in eyes. Immediately wash away casual splashes plentiful amount of clear water. Remember that hit even of insignificant amount of brake fluid in a digestive tract is fraught with the most serious consequences, up to a lethal outcome. Some types of hydraulic liquids are also combustible and can ignite at contact with the surfaces warmed to rather high temperature - observe the appropriate measures of fire safety. Along with toxicity, brake fluid differs in the increased chemical aggression and is capable to damage easily a paint and varnish covering of body panels of the car. At hit of liquid on body elements immediately wash away its traces a plentiful amount of water. At last, it is necessary to draw the attention of the reader to high hygroscopicity of brake fluid. The last means ability to absorb the moisture which is contained in it from air that speaks about the inadmissibility of use which was long kept in untightly closed liquid container. Add in system only fresh hydraulic liquid of the required grade.

On the models equipped with ABS before a rassoyedineniye of hydraulic brake lines without fail switch-off the rechargeable battery. It is necessary to connect the battery only after connection of all hydraulic lines of a brake path. Violation of this requirement is fraught with hit in the hydraulic modulator of air which removal in the course of usual pumping of system is not possible and demands use of a special electronic tester (VAG 1552).

General information

It is possible to achieve serviceability of functioning of any hydraulic system only, having completely removed air traffic jams from its path. Removal of air from the brake system is made by its "pumping".

In the course of performance of pumping of the brake system add in it only fresh hydraulic liquid of the required grade. The liquid merged from system is not subject to the repeated use. Before starting implementation of the procedure make sure available a sufficient reserve of fresh brake fluid.

In the presence of the slightest suspicions on presence at system of low-quality brake fluid the hydraulic path has to be washed carefully out by fresh liquid of the required grade. Besides, it is necessary to replace everything the systems of a cuff used in components and lines and sealing rings.

In case of loss of hydraulic liquid or hit in system of air as a result of development of leaks, before pumping it is necessary to eliminate all defects taking place.

Tire out the car on a platform / a viewing hole, muffle a distance, cock the parking brake and turn on the first or reverse gear, then prop up wedges back wheels. Alternatively the car can be поддомкрачен and is installed on reliable props (for the purpose of simplification of access remove wheels).

Check reliability of fastening of nipple connections of brake lines and gates of pumping of supports / wheel cylinders. Carefully wipe outside gates and surfaces surrounding them.

Uncover and add fresh hydraulic liquid in the GTTs tank, having brought its level to mark MOVE. Again freely screw a cover. Remember that in the course of performance of pumping of system liquid level in the tank should not fall below the mark MIN, otherwise air can get to the cylinder and all made efforts will come to nothing.

Now in shops of automobile accessories it is always possible to acquire the special sets allowing to make pumping of the brake system of the car by forces of one person. Use of such set considerably simplifies the procedure of pumping and reduces risk of suction of the hydraulic liquid and air which is back already extorted from it. If special set is not had near at hand, it is necessary to resort to the help of the assistant. The description of procedures of pumping of the brake system is stated by forces of one and two people below in the corresponding subsections.

When performing pumping of a hydraulic contour with use of special set the car has to be prepared for the procedure according to the instructions given above. Further it is necessary to work according to the instructions attached to set. The general principle of use of such sets is stated below in the corresponding subsections.

Regardless of what method of pumping will be chosen, the sequence of implementation of the procedure has to remain invariable, being the key to completeness of removal of air from a hydraulic path.

Sequence of performance of pumping

PERFORMANCE ORDER

1. If pumping of system is made for the purpose of removal of the air which got to the highway as a result of a detachment of components of only one of parts of a hydraulic contour there will be only a concrete brake mechanism given to pump over enough.
2. In case of need removals of air traffic jams from all system, the sequence of performance of pumping has to be following:

a) Brake mechanism of the right back wheel;
b) Brake mechanism of the left back wheel;
c) Brake mechanism of the right forward wheel;
d) Brake mechanism of the left forward wheel.

Basic method of performance of pumping of the brake system by forces of two people

PERFORMANCE ORDER

1. Prepare suitable drain capacity with transparent walls, a piece of a plastic tube or the rubber hose which is densely getting on the pumping gate, and a cap key for turning of the gate. Get support of the companion.
2. Remove a dustproof cap from the gate of pumping of the corresponding brake mechanism, put on a head of a cap key the gate, afterwards pull a hose which second end should be lowered in the transparent capacity which is partially filled with pure brake fluid. The cut of a hose has to is completely shipped in liquid.
3. Make sure of sufficiency of level of liquid in the GTTs tank. Remember that during the whole time of implementation of the procedure the level of liquid should not fall below the mark MIN.
4. Ask the assistant to squeeze out a little against the stop a pedal of a foot brake for the purpose of creation of pressure in system. On the last step the pedal should be recorded in the lower situation.
5. At the withheld squeezed-out pedal of a foot brake unscrew (approximately on one turn) the gate of pumping and observe behind deflation through a hose in the drain capacity of the liquid containing air bubbles. The assistant has to press constantly a pedal until it does not rest against a floor. When the liquid effluence from a hose stops, tighten the gate of pumping and ask the assistant to release a pedal slowly. At once check liquid level in the GTTs tank, in case of need make adjustment.
6. Repeat performing procedures of paragraphs 4 and 5 until the hose does not begin to come out liquid, transparent, free from air bubbles. If pumping of the first in the order of the brake mechanism of system after depletion of GTTs is made, the pause between cycles has to make not less than five seconds necessary for filling with liquid of internal cavities of the cylinder.
7. Having finished pumping, strongly tighten the gate, remove from it a hose and a cap key and establish a dustproof cap.

Do not tighten the gate too hardly.

8. In case of need repeat the procedure, in the required order having pumped over brake mechanisms of the remained car wheels for the purpose of full removal of air from a hydraulic path.

Order of performance of pumping of the brake system with use of set with the unilateral valve

PERFORMANCE ORDER

1. As appears from the name of set, its main component is the unilateral valve which is built in in a drain tube and providing its unilateral passability. Transparent drain capacity has to be established so that freely to be looked through from the driver's place in interior of the car.

2. The drain tube one end puts on on the pumping gate which is left open for all the time of implementation of the procedure. Further the operator sits down on the driver's place and begins to squeeze out and release smooth uniform motions a pedal of a foot brake until the tube does not begin to come out brake fluid, transparent, free from bubbles.

3. Do not forget about need of maintenance of level of liquid for the GTTs tank.

Order of performance of pumping of the brake system with use of set with a source of compressed air

PERFORMANCE ORDER

1. As an autonomous source of compressed air the spare wheel of the car in which it is necessary to dump pressure a little below normal is usually used (see instructions of manufacturers of set).
2. Due to connection to the GTTs tank of the compressed air of a container filled with hydraulic liquid and connected to a source the operator is exempted from need of a manipulation by a pedal of a foot brake. Now it is rather simple to open and close the gate, watching the liquid which is forced out from system.
3. The method is good the fact that existence of a sufficient reserve of hydraulic liquid in the container connected to the GTTs tank allows not to worry about need of tracking its level.
4. This method is especially effective when pumping paths with the lowered passability, and also when replacing brake fluid during performance of routine maintenance of the car.

All methods

PERFORMANCE ORDER

1. Upon completion of pumping of system and restoration of feeling of normal hardness when squeezing a pedal of a foot brake, check reliability of tightening of gates of pumping, collect by rags traces of the spilled liquid and make sure that did not forget to put on dustproof caps gates.
2. Check the level of hydraulic liquid in the GTTs tank, in case of need make the corresponding adjustment.
5. The hydraulic liquid merged from system is not subject to reuse and has to be handed over in special place of acceptance on utilization of toxic waste.
4. Make sure of an isprvnost of functioning of a pedal of a foot brake. If the feeling of softness when squeezing a pedal remained, therefore, is removed from system not all air and the procedure of pumping it is necessary to repeat. If to remove air from a path and during repeated pumping it is not possible, check a condition of sealing cuffs of GTTs.

At emergence of the slightest doubts in an isprvnost of functioning of the brake system on the equipped ABS models the car should be driven away immediately on car repair shop for performance of diagnostics of a condition of the hydraulic modulator with application of a special tester of VAG 1552.