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Diagnostics of malfunctions of brake system

Overly tight brake pedal is depressed

Mounted brake pads (disc brakes) or friction linings of shoes (drum brakes) is not the type. Check, replace.

Broken patency brake line from the brake master cylinder (GTZ). Check the line, remove the cause of the lock, or make replacement.

Conjuring the axis of the brake pedal. Perform the necessary repairs or replace the axle bolt and sleeve.

Jammed piston wheel cylinder / caliper. Overhauled cylinder / caliper.

Disrupt the functioning of the brake servo. Check the amplifier (see chap. Brake System).

There is a "tacking" brakes

Broken cross-fittings GTZ. Check, clean the GTZ and the brake fluid reservoir.

Jammed piston wheel cylinder / caliper. Perform the necessary repairs.

Jammed the parking brake cable. Replace the cable.

Broken or stretched spring tensioning drum brake shoes. Replace the defective spring.

Disturbed adjustment servo pushrod / GTZ. Check, make the necessary adjustments.

In order to detect signs of tacking Poddomkratte brakes the car and establish it on props. Alternately rotate the wheel by hand, do not check whether the brake is stuck. If all the wheels rotate freely, ask the assistant to squeeze and release the brake pedal. Make sure that the brakes "release" wheel without delay. Violation of the cross fitting GTZ is simultaneous tacking two wheels, brakes which are included in the particular hydraulic circuit. Release valve pumping on one of the wheels stuck, making sure that the cause of tack is to increase the pressure in the circuit. Wedging drive parking brake cable usually leads to tacking the rear propeller shaft. To check Poddomkratte back of the car and establish it on props, remove the drive cable from the executive lever - rear propeller shaft should begin to rotate freely.

There have been noises issued brakes

Braking is accompanied by a squeal. Zapolirovat material friction linings. Remove the suspected pads / shoes (see. Accompanying illustration) and remove polish from the surface using sandpaper.

Braking is accompanied by grinding. Worn material friction linings. Check the condition of pads / shoes and disc / drum brake suspects. Replace worn pads / shoes, give to bore a damaged disc / drum (see. Accompanying illustration).

Screeching brakes in most cases is caused zapolirovyvaniem polished surfaces of the friction brake linings, but we should not lose sight of the possible causes of such as using the wrong type of shoes, as well as the loss of antivizgovyh protivoskripnyh springs or pads. If there is a deterioration of the friction lining pads / shoes to the metal substrate to be replaced every four pads / shoe, even if they are on the opposite wheel are in good condition. With strong istsarapyvanii brake disc / drum should be machined or replaced to restore the braking efficiency.

We have the lowest "softness" stroke of the brake pedal

Faulty automatic regulator rear brakes. Carry out the necessary repair or replace the regulator.

Fell brake fluid level. Check for signs of leaks - inspect all couplings (see para. Accompanying illustration). Perform the necessary repairs to restore the fluid level and bleed the hydraulic system.

The hydraulic system is air. Bleed the system.

In most cases, the "softness" of the brake pedal stroke is associated with a hit in the hydraulic system of air. Be sure to find the source and eliminate air infiltration having a defect (seals or couplings). Then the system must be bled. Defective components of the brake system is easy to determine by the presence on the surface traces of leaks of a brake zhidkosti.Pri braking wheel lock

There is brining the friction lining pads / shoes due to contamination from oil or brake fluid. Identify and eliminate the cause of contamination, replace the pads / shoes.

Warped brake drum. Check that make the necessary replacement.

Installed pad / shoe covers are not the type. Check, replace.

Broken or stretched brake shoe return spring. Check, replace defective spring.

Faulty pressure control valve. Replace the valve.

Remove all the wheels and vote wear friction pads and check them for signs of oil contamination. Check the condition of clamping springs, brake shoes, comparing their free length to that of the new spring. A sign of the deformation of the brake drum is the pulsation of the brake pedal with a light braking. If the rear wheels are locked permanently, check the operation of the pressure regulator.

We have the pedal pulsation during braking

Warped brake drum / disc. Inst defective component.

Worn wheel bearings front or rear wheels, or weaken their preload. Adjust the preload or replace defective bearings.

Warped brake drums / disks to be a bore. This work should be entrusted to specialists Car workshop, which will also help you determine the feasibility of this procedure. You may need to purchase new components.

There is a "withering" brakes

There has been friction linings brining shoes / boots due to contamination from oil or brake fluid. Identify and eliminate the cause of contamination, replace the pads / shoes.

Warped brake drum. Check that make the necessary replacement.

Faulty automatic regulator rear brake. Perform the necessary repairs to the regulator.

Installed pads / shoes are not the type. Make replacement.

Contaminated brake fluid. Empty the hydraulic system and fill with fresh brake fluid. Bleed the brakes.

In most cases, brake fade is due to perform sudden and frequent braking, leading to heating of the friction linings and disc / drum brakes. After ostuzhennoy braking mechanism should bounce back.

Overheat brake

It has failed the automatic control of the rear wheel brake. Perform the necessary repairs.

Broken or stretched brake shoe return spring. Check, replace defective spring.

Disturbed adjustment servo pushrod / GTZ. Check, make the necessary adjustments.

Jammed piston wheel cylinder / caliper. Perform the necessary repairs.

Damaged or blocked hose / tube hydraulic brake line (see. Accompanying illustration). Eliminate the cause of the lock, or replace the defective hose / tube.

Locked fitting GTZ. Check, clean the cylinder and the reservoir of brake fluid.

Too sharp braking is done. Change the style of driving.

To check the brakes on jamming Poddomkratte car and establish it on props. Alternately turn each of the wheels by hand. If the piston of the wheel cheers / caliper of a brake jammed, it makes sense to check and make regenerative repair of cylinders / calipers and GTZ.

There was a brake failure

GTZ has failed. Remove the cylinder, follow its refurbishment, bleed the hydraulic system.

Fell brake fluid leaks due calipers / wheel cylinders. Perform the necessary repairs, bleed the hydraulic system.

The liquid level has fallen as a result of leakage of brake hoses / tubes. Replace defective components, bleed the hydraulic system.

The hydraulic system is air. Check and correct the cause, bleed the system.

Contaminated brake fluid. Drain the system, fill the fresh liquid, bleed the brakes.

To find sources of leaks GTZ fill with brake fluid and ask the assistant to shake the foot brake pedal. Themselves at the same time try to visually register the external leakage of fluid.