Brake Drive Booster (Renault Espace I)

1. Do not repair the brake booster yourself, as this requires special tools. A failure of the booster does not result in a loss of braking, it only requires applying more force to the brake pedal to have the same braking distance. If you allow the car to roll down a slope with the engine off, remember that after several braking operations the pressure in the system drops and the brakes then work without a booster. The muscular effort when pressing the brake pedal will be correspondingly greater.

2. To access the brake booster, remove the master cylinder. Also, depending on the vehicle design, remove all other components. Use a spring clip and a bolt with a hole for a cotter pin to secure the push rod to the brake pedal. Disconnect the vacuum hose from the booster.

3. Replace the filter on the end of the push rod. To do this, stick a pointed tool into the filter and pry it out. Cut out a new filter and install it on the push rod.

4. If a new brake booster is to be installed, the push rod must be positioned between the fork head hole and the support surface of the new brake booster:

5. Disconnect the push rod from the brake pedal and from the control lever and set the value "A" to 112.5±0.5 mm. Tighten the lock nut again. Length "L" (see illustration 19.5a) should be 105.0 mm. On the other side of the brake booster, measure the protruding portion of the master cylinder actuator pushrod ("X" in Illustration 19.5b). The value should be 22.3 mm, and cannot be adjusted.







Material taken from an online portal renaultbook

6. For second generation vehicles, set the "b" value to 161.0 mm for 4-cylinder engines, or 149.0 mm for a V6 engine (see illustration 19.5b). To do this, loosen the lock nut and move the fork head. Tighten the lock nut again. The "X" dimension is also not adjustable and should be 22.3 mm on all models.