Porshe 911 (997). Manual - part 298

- Notes
- Bleeding the brake system

Notes

Note

Observe brake-fluid quality! Use only new DOT 4 brake fluid!

• 

The Super DOT 4 brake fluid must be changed every two years!

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This brake fluid is available under the following part numbers: Container quantity 1 litre =
000.043.203.66 Container quantity 30 litres = 000.043.203.67

• 

Bleeding the brake system

Procedure for bleeding

1st. Step: Bleed brakes in the normal way (in combination with bleeding device at the brake fluid reservoir
and 2.0 bar pressure) (primary circuit).
2nd. Step: In addition, use the Piwis Tester to bleed the brakes (secondary circuit). Only necessary if the
hydraulic unit has been replaced and, after bleeding in the normal way (primary circuit), the brake pedal travel
is excessive.

1. Step: Bleeding (primary circuit)

Note

Always bleed both bleeder valves on brake caliper!

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Bleed the outer bleeder valve first!

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Note

If the pedal travel is too long or the pedal feels too soft when applied, carry out bleeding again.
Operate (pump) the brake pedal at the same time. A second person is required for this.

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Also carry out this procedure if the brake hydraulic system was largely empty.

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Cover over brake fluid reservoir

1. Disengage and remove cover over brake fluid reservoir -B- .

2. Open expansion tank.

Bleeding brakes

3. Connect a bleeding device to the brake fluid reservoir. Switch on the bleeding device. Bleeding

pressure is approx. 2.0 bar.

4. Continue the bleeding procedure at the brake calipers. Do so in the following sequence: rear right/rear

left/front right/front left. Bleed the outer bleeder valve first.

5. Use a transparent hose and a collecting bottle to check the escaping brake fluid is clean and free of air

bubbles and to determine the amount of brake fluid used.

6. Open each bleeder valve until clear, bubble-free brake fluid emerges.

7. Tighten the bleeder valves to the stipulated tightening torque and remove the bleeder hoses.

8. Generate vacuum in brake booster by starting engine. Check brake-pedal travel and pedal

feel.

Check the brake system for residual air by the amount of brake pedal travel. Repeat the bleeding procedure if
necessary. Operate (pump) the brake pedal at the same time as described below. This will remove the
remaining air bubbles from the primary circuit.

Diagnostic system: reading out fault memory and activating systems

1. Step: Bleeding (primary circuit)

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Open the rear right bleeder valves, then fully rapidly depress the brake pedal hard several times. Hold
the brake pedal for 2 to 3 seconds after each depression, then release slowly. Continue bleeding until
the brake fluid emerging into the collection bottle is free of bubbles and foam.

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Repeat this procedure in the sequence rear left/front right/front left.

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9. If necessary, continue bleeding the secondary circuit (using the Piwis Tester). Only necessary if the

hydraulic unit has been replaced and, after bleeding in the normal way (primary circuit), the brake
pedal travel is excessive.

Brake fluid level

10. Remove bleeding device from brake fluid reservoir and screw cap on. The brake fluid level in the brake

fluid reservoir must be between the MIN and MAX markings once the vehicle has been filled and bled.
Adjust the brake fluid level if necessary.

2nd Step: Bleeding (secondary circuit)

Bleeding of the secondary circuit is only necessary if the hydraulic unit has been replaced and, after bleeding
in the normal way (primary circuit), the brake pedal travel is excessive.
First bleed brakes as usual (primary circuit). Only then can you carry out bleeding of the secondary circuit
with the Piwis Tester. The process is menu-driven. You must observe the specified sequence rear left, front
left, front right, rear right.
To bleed the secondary circuit, the bleeding device remains connected to the brake fluid reservoir. Bleeding
pressure is approx. 2.0 bar.
Throughout the entire bleeding process, the brake pedal must be operated cyclically (hold depressed for 2 to 3
seconds, then release slowly). After operating pedal for the last time, hold the brake pedal down and close
bleeder valve.

997110, 997111, 997120, 997121, 997310, 997311, 997320, 997321, 997410, 997411, 997430, 997431,
997610, 997611, 997620, 997621

WARNUNG

Gefahr des Verlusts der Text-Bild-Zuordnung beim Ausdruck.

Diagnostic system: reading out fault memory and activating systems

2nd Step: Bleeding (secondary circuit)

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Aus technischen Gründen kann derzeit nicht ausgeschlossen werden, dass trotz
einwandfreier Darstellung auf dem Bildschirm beim Ausdruck der
Zusammenhang von Text und zugehörigem Bild verloren geht.

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Wird der Fehler nicht bemerkt, besteht die Gefahr, daß Arbeiten nicht korrekt
durchgeführt werden und es dadurch zu Personen- und Sachschäden kommt.

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→ Vergleichen Sie deshalb nach dem Druckvorgang unbedingt die Ausdrucke mit der
Bildschirmdarstellung. Korrigieren Sie die Ausdrucke im Fehlerfall so, daß der Inhalt der
Bildschirmdarstellung zutreffend wiedergegeben wird.

WARNING

Danger of losing text-figure correspondence when printing out.

For technical reasons, it can currently not be ruled out that the correspondence
between text and associated figure can be lost when it is printed out, even though
the display on the screen is correct.

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If the fault is not noticed, there is the danger that work will not be performed
correctly which can cause injury and damage.

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→ Therefore, always compare printouts with the screen display after printing them out. Correct
the printouts if they are faulty so that the content of the screen display matches that on the
printouts.

AVERTISSEMENT

Risque de perte de la correspondance texte-illustration lors de l'impression papier.

Pour des raisons techniques, il ne peut pas être exclu à l'heure actuelle que, même
en cas d'affichage correct à l'écran, la correspondance entre le texte et l'illustration
puisse être erronée sur l'impression papier.

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Si l'erreur passe inaperçue, on court le risque d'exécuter certaines opérations de
manière incorrecte pouvant conduire à des dommages corporels et matériels.

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→ Comparez impérativement pour cette raison les impressions papier avec l'affichage à l'écran.
Corrigez-les en cas d'erreur de manière à reproduire correctement l'affichage à l'écran.

ATTENZIONE

Pericolo di perdita dell'abbinamento testo-immagine nella stampa.

Per motivi tecnici non è escluso che, nonostante la rappresentazione sullo schermo
risulti perfetta, durante la stampa venga persa la corrispondenza fra testo e
relativa immagine.

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Se tale difetto non viene rilevato vi è il pericolo che i lavori non siano eseguiti
correttamente; ciò può avere come conseguenza lesioni e danneggiamenti.

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→ Per questo motivo, dopo la stampa è assolutamente necessario confrontare le stampe con la
rappresentazione sullo schermo. In caso di errore si prega di correggere le stampe, così da
garantire la riproduzione esatta della rappresentazione sullo schermo.

Diagnostic system: reading out fault memory and activating systems

2nd Step: Bleeding (secondary circuit)

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