Poor trigger rear brakes

Rear brake rarely make themselves known, because rarely used front and, therefore, auto-owners rarely go stare. And in vain, because the drum brake mechanism can also stop working, and thus cause problems. What if a car is bad trigger rear brakes, tells the publication. In the early 20 - century were the most effective drum brake system, in this type of brake pads, having a semicircular shape, clamped to the inside of the cast iron drum. To date, the principle of operation of this system has changed little. Purpose and design of drum brake system, as all brake systems, designed to slow the spinning wheel as long as it is a complete stop. Drum brakes are placed not only on the rear wheels, but also on the front. But because of low efficiency, often to the rear axle. The main elements of a drum brake: · brake cylinder, brake drum · · brake shield · return spring; · two brake pads. Backing plate is attached to the wheel boom. On the backing plate installed operating the brake cylinder. By pressing the brake pedal in the brake cylinder pistons diverge to the sides and push the brake pads. Blocks, in turn, pressed against the inner surface of the brake drum, which rotates with the wheel (the wheel to put on the drum), while slowing its rotation to a full stop. To stop braking, you need to let go of the brake pedal. At the same time stop the pressure on the brake pads, and return them to their original positions special return spring. Friction and contact between the brake drum and shoes stopped and now nothing prevents the wheels rotate freely. Symptoms and causes of error Since the rear wheels are involved in slowing the vehicle is less than the front, the car owner did not immediately notice that the rear brakes poorly triggered because usually decrease gradually. The problem becomes most noticeable when the vehicle speed decreases more slowly than usual, with active braking. If a breakdown occurred only on one wheel, the car can skid when braking on slippery roads. If the car while driving in reverse slowing worse - this also indicates a fault on the rear brakes. Very undesirable leakage of brake fluid, since the loss of a significant part, off a brake circuit - this leads to poor slowing the car. In contact with air in the hydraulic system, the brake pedal is usually softer. And inhibition starts only at the end of its stroke, or after "inflation". Misalignment of brake pads can occur for different reasons. One of the reasons - it's disconnecting the friction linings. Likewise, the reason may be the fault of springs and / or racks. In this case, the pads make sounds, as the scratching on the brake drum. In addition, failure can lead to jamming drum to overheat, an increase in fuel consumption, as well as capable of reducing the distance of the car coasting. Species most common cause of failures to reduce the efficiency of the drum mechanism - a worn-out brake pads and / or drums. In the former case, erasing friction linings, in the second case, increasing the circumference of the working surface. If these elements are critically deteriorated, this can lead to expulsion from the piston cylinder, and to further leakage of hydraulic fluid. Can jam the wheel. By leaking brake fluid can also cause wear and / or damage to the cuff of the cylinder. Brake fluid, which follows immediately gets on the pads, that is not the best way affects the work shoes. Leakage occurs when there is damage to the rubber cylinder sleeves. As a result, leaking brake fluid from the system out, and immediately going on air leak in it. If there was a partial loss of containment, the performance of the system becomes lower due to the "airing", and / or "lubrication" pads leaked fluid. At easing parking brake cable, push force pad is reduced. Diagnosis Efficient diagnosis performance drum brake is possible only on a special stand. On the stand is calculated as a percentage, how effective the work of each mechanism. If, for some - the reason you do not have the opportunity to visit the SRT, then you can test the effectiveness of inhibition by heavy braking at speeds of 60-80 km / h on a dry and level road. The car thus should move straight, even if the wheel lock. But when such a test results may affect the non-uniform loading of the car. Such testing must be done several times. Also, for any violation in the parking brake is necessary to diagnose the drum mechanism. Note: When you wear at any point up to the limit, at least one of the pads, you should replace all four pads. Replace all pads are needed in case one of the pads contaminated with oil, because there is no good way to degrease oily friction linings. If you install a new brake drum, then you need to remove the nitro solvent protective coating drum of it can be covered from the inside. Warning: Do not press the brake pedal until the brakes are fully assembled. New shoes until the run-in, can not guarantee the full effectiveness of braking, so after replacing the pads until they run over a couple hundred miles, as far as possible to avoid sudden braking.