Checking the position of the brake pedal

The correct position of the brake pedal in the free state and when pressed to the stop (pedal travel) serves as one of the criteria for checking the health of the brake system. At the same time, the position of the pedal largely ensures the correct operation of the system. If the pedal is at a distance from the floor that is greater than the standard, the wheels may not completely release when the pedal is released (there is usually no free play of the pedal). If the pedal is too low, there may be reduced brake performance due to reduced pedal travel. Adjustment of the position of the pedal is not provided, it is provided constructively with the serviceability of all parts of the brake drive. In case of deviation of the nominal position, check the condition of all parts and components of the drive and replace the faulty ones.

You will need a ruler.



1. Start the engine, let it idle and depress the brake pedal vigorously several times.

2. Pull the brake pedal up with your hand until it stops.

3. Release the pedal and measure the distance from the pedal pad to the floor.

NOTE: The ruler must be set perpendicular to the floor plane.

4. Vigorously press the brake pedal to the stop.

5. Release the pedal and re-measure the distance from the pedal pad to the free floor. The pedal should return to its original position by the distance measured in step 3 from the pedal pad to the floor.

6. Check the free play of the brake pedal, for which move the pedal by hand until the pedal stops moving without resistance. Determine the value of the free play on the ruler, it should be 1-3 mm. The non-compliance of the free play with the specified range of values \u200b\u200bcan be caused by the following reasons: - Increased play in the connection of the pusher fork of the vacuum booster and the pedal. This may be due to wear on the fork pin; – Jamming of pistons in the main brake cylinder; - Jamming of the plunger in the brake booster.

7. If the distance from the pedal pad to the floor when remeasured (item 5) less than the value measured in paragraph 2, this indicates the pedal is stuck on the axle, the pistons in the working and master cylinders are jammed, or the compensation holes in the master brake cylinder are clogged.

NOTE: Compensation holes in the master cylinder can be blocked by cuffs swollen due to ingress of petroleum products into the system, as well as due to the use of low-quality brake fluid.

8. Stopping the pedal when pressed almost at the very floor indicates the presence of air in the hydraulic brakes or the wear limit of the brake pads, brake discs or drums. If there is air in the system, the pedal stops farther from the floor with a few repeated presses ("pumped up").

WARNING: If the pedal is pressed all the way down and held in this position gradually moves to the floor, fluid has leaked from the hydraulic drive or the brake master cylinder is faulty. These malfunctions are very dangerous, so find the leak immediately and fix it or replace the brake master cylinder!