10.3. Check of serviceability of functioning of the vacuum amplifier of brakes

Check of serviceability of functioning of the vacuum amplifier of brakes

030 — the Vacuum gage
051 — the Tester

060 — the Measuring instrument of effort of squeezing of a pedal


  1. Connect the vacuum gage (030) to the brake amplifier, then several pressing a pedal of a foot brake dump depression in a vacuum path.
  2. Connect a tester (051) to the service union, or to a support of the brake mechanism.
  3. Connect the measuring instrument (060) to a pedal of a foot brake.
  4. Start the engine and a sharp otpuskaniye of the squeezed-out accelerator pedal create the required depression (0.60 ÷ 0.80 atm) in a vacuum path.
  5. If depression falls at once, or its depth is insufficient, it is necessary to check a condition of the sealing ring established between the servo-driver of the vacuum amplifier and GTTs, also the probability of failure of the control valve in the vacuum line is not excluded. Estimate a condition of retaining valve, and also lines and a vacuum receiver of the drive of blocking of differentials. On diesel models make sure of serviceability of functioning of the vacuum pump. Replace the failed components.
  6. Squeezing out a pedal with the required efforts, consider the indication of a tester. Compare results of measurements to requirements of Specifications.
  7. Disconnect the measuring instrument (060), a tester (051) and the vacuum gage (030).
  8. Pump over the brake system (see the Section Pumping of the Brake System).

Only the contour of the brake mechanism of the corresponding wheel needs pumping.