Replacing the vacuum booster (Renault Sandero 1)

The vacuum brake booster is a complex, difficult to disassemble structure. Its adjustment and repair require qualified personnel and special equipment. In addition, the booster is a device that directly affects traffic safety, and poor-quality repairs can lead to serious consequences. Therefore, in the event of a malfunction, replace the entire booster. Methods for checking the performance of the vacuum brake booster are described in the subsection "Checking the operation of the brake booster".

You will need: a flat-blade screwdriver, a 13 mm socket head.

Helpful advice.

• 
• To unscrew the hard-to-reach nuts that secure the vacuum booster, you will need a set of socket heads, extensions, and ratchets similar to the one shown in the photo.

1. Disconnect the wire from the negative terminal of the battery.



2. Disconnect the hose from the vacuum booster to the inlet pipe by prying off the hose check valve with a screwdriver.



3. Remove the brake master cylinder (see "Replacing the master brake cylinder").

Helpful advice.

• 
• If the performer has sufficient skills, the main brake cylinder does not need to be completely removed; it is enough to disconnect it from the brake booster and move it forward without disconnecting the pipes from it.

4. Using a screwdriver, remove the two soundproofing holders...



5. ...and remove the cover.





6. Disconnect the brake booster pushrod from the brake pedal by unfastening the spring pin retainer from the pedal...



7. ...and, squeezing the plastic retaining ring...



8. ... remove the pin from the holes in the pedal and pusher fork.

Note.

• 
• Replace the brake booster pushrod pin if it is worn or if the spring clip and snap ring are damaged.

9. Unscrew the four nuts securing the brake booster to the front shield...





10. ...and remove the vacuum booster.

11. Install the vacuum booster and all removed parts in the reverse order of removal. Before installation, check the booster adjustment dimensions (Fig. 9.9) and, if necessary, restore them by turning the booster rod adjustment bolt (dimension X) and the pusher fork with the lock nut (dimension L) loosened.

Note: The booster rod adjustment bolt is secured against loosening during operation with anaerobic thread lock.

12. If the brake master cylinder was completely removed, fill the brake fluid and bleed the air from the system (see "Bleeding the hydraulic brake system").