When increasing the force on the brake pedal, it is necessary to check the performance of the vacuum booster

Checking the brake booster

Depress the brake pedal to the stop several times with the engine off and, keeping the pedal depressed, start the engine.

At the same time, due to the pressure drop in the cavities of the booster, the brake pedal should move forward.

If this does not happen, check the tightness of the vacuum booster hose connections and, if necessary, eliminate air leakage.

If this still fails, then the amplifier is defective and needs to be replaced.

To check the tightness of the vacuum booster, open the hood and start the engine for 1 minute.

Approximately 30 seconds after the engine has been turned off, press the brake pedal 2 times, while a characteristic hiss of air entering the amplifier should be heard.

Otherwise, replace the amplifier.

Blow out the hose with check valve at both ends.

Air must only pass through the side of the non-return valve. Otherwise, replace the non-return valve.

Replacing the vacuum brake booster

Remove the main brake cylinder without disconnecting the brake pipes from it (see Removing the main brake cylinder).

Replacement of vacuum brake booster for Gazelle

Loosen the clamp with a screwdriver

Replacement of vacuum brake booster for Gazelle

Remove the vacuum supply hose from the fitting.

Replacement of vacuum brake booster for Gazelle

The hose can also be removed with the fitting.

Replacing the vacuum brake booster of a Gazelle car

Remove the lock washer from the cabin side with a screwdriver.

Replacing the vacuum brake booster of a Gazelle car

Holding the pusher eye bolt with the “19” key, unscrew the nut with the “17” key

Replacing the vacuum brake booster of a Gazelle car

Remove the bolt from the pusher eye.

Replacement of vacuum brake booster for Gazelle

Remove two plastic bushings from the pusher eye

Replacing the vacuum brake booster of a Gazelle car

Using a “13” head with an extension from the cab, unscrew the four nuts securing the amplifier to the partition of the engine compartment

Replacing the vacuum brake booster of a Gazelle car

Remove the amplifier.

Replacement of vacuum brake booster for Gazelle

Remove the paronite gasket.

Replacement of vacuum brake booster for Gazelle

We install the new vacuum booster in the reverse order, while for the correct operation of the brakes, the position of the adjusting bolt should be adjusted.

Replacement of vacuum brake booster for Gazelle

To do this, holding the pusher with the “8” key, unscrew the lock nut with the “10” key.

Then, with the “8” key, unscrewing or tightening the bolt, ...

Replacing the vacuum brake booster of the Gazelle car

We achieve such a position in which the gap between the mating plane of the amplifier and the bolt head is within 1.35–1.65 mm.

Replacement of vacuum brake booster for Gazelle

After that, while holding the bolt, tighten the locknut.

Having lubricated the plastic bushings, we install the booster, after which we adjust the brake pedal travel.

To do this, holding the pusher of the amplifier with the “8” key (for clarity, it is shown on the removed amplifier), unscrew the lock nut with the “14” key and, ...

Replacement of vacuum brake booster for Gazelle

By rotating the pusher eye, we set the distance between the center of its hole and the mating surface of the vacuum booster housing - 131–133 mm.

Installing the master brake cylinder.

The free travel of the brake pedal with the engine off should be 3–5 mm.