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Front disc brakes
WARNINGS Every time you work with the braking system, remember that the abrasion of brake pads generate dust which contains asbestos, unhealthy, so when cleaning the brake pads do not use compressed air and do not inhale the dust. To clean the brake, use only the special brake cleaner. |
Replacing the brake pads Withdrawal If before replacing the brake pads then filled with brake fluid, it is necessary to pump as otherwise flowing from the brake fluid reservoir damage the adjacent varnish surfaces and components in the engine compartment. For pumping the brake fluid using absolutely clean pipette or old medical syringe - never suck away the liquid by mouth.
If you are driving and braking squeal brake pads, check the brake pads. Remove the front wheel. Through the inspection window, check the thickness of the caliper brake linings. If the thickness of the brake linings does not match the specifications, replace them. The thickness of the brake linings: - Par - 10.75 mm; - Minimum allowable - 2.0 mm.
| Fig. 6.13. Reversing the caliper guide pin
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| Fig. 6.14. Elements of the front disc brake 1 - a support to the cylinder; 2 - cuff; 3 - the piston; 4 - dust cover; 5 - directing the brake pads; 6 - a spring clip; 7 - a lining; 8 - the brake pads; 9 - dust cover; 10 - a directing finger; 11 - the screw to remove the air
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Remove the two directing fingers and remove the caliper from the master cylinder (Fig. 6.13.). Elements of the front disc brake shown in Fig. 6.14 Hang the caliper from the master cylinder to the wire.
A WARNING Do not disconnect from the caliper brake hose. |
Remove the brake pads.
A WARNING Do not press the brake pedal with the brake pads removed. |
Check Check pads for wear or contamination and replace them if necessary. Check the gasket for damage or deformation. Setting Install spring clamps brake pads. Install the brake pads for each spring clip.
A WARNING Brake pads of left and right wheels must be replaced in the kit. Place the block so that the wear faces upward, and the block in the side of the piston. Before the installation, remove the rust with spring clips, or if they are damaged, replace them with new ones. |
| Fig. 6.15. Using the handle of a hammer to force the piston in the cylinder of a support
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Hammer handle press the piston into the cylinder support (Fig. 6.15). When retracted, the piston brake liquid is superseded from the brake cylinder in a broad tank, so constantly observe of liquid level in the tank and, if necessary, evacuate it from the tank. Lower caliper and install the cylinder, being careful not to damage the protective cover. Replace the two guide pin and tighten to 22-32 Nm.
Caliper front disc brake Withdrawal Remove the front wheel. Disconnect the brake hose from the caliper.
A WARNING To eliminate leaking brake fluid, close the hole of a brake hose stopper or a segment of a rubber hose of suitable diameter. |
| Fig. 6.16. Location bolt of the brake pads caliper to the steering knuckle
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Remove the bolts guide brake pads caliper to the steering knuckle (Fig. 6.16). Remove the caliper. Dismantling Remove the guide pins and remove the caliper from the brake pad guide.
| Fig. 6.17. Removing the dust cover with a screwdriver piston
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Flat-blade screwdriver, remove the dust cover of the piston (Fig. 6.17). Set the caliper brake pads in place a piece of wood and feeding the compressed air through the opening for connecting the brake hose, squeeze out the piston from the cylinder support.
WARNINGS Do not leave your fingers in front of the piston in the compressed air supply. Be careful with compressed air is not spilled brake fluid. |
| Fig. 6.18. Use a screwdriver to unscrew the cuff piston caliper
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Use a screwdriver to remove the sleeve from the caliper piston (Fig. 6.18). Brake fluid, clean the outer surface of the piston and the inner surface of the cylinder support. Check Check the support cylinder for wear, damage and corrosion. Inspect the piston for wear, damage and corrosion. Check base metal brake pad for damage and cover pads for traces of oil. Check the wear indicator for damage. Dial gauge and micrometer to measure the thickness of the beating and the brake disc. If necessary, treat or replace the brake disc. Brake Disc Thickness: - Nominal - 24.5 mm; - The minimum allowed - 22.4 mm. The maximum permissible difference between the thickness of the brake disc - 0.005 mm. If necessary, replace the brake disc as follows: - Lift the car and fix it on support; - Remove the wheel; - Remove the caliper assembly from the steering knuckle and secure it with wire rack; - Remove the hub front brake rotor. Assembly Clean all parts with isopropyl alcohol, except for brake pads and linings. Lubricate the piston sleeve and cuff set in the cylinder. Lubricate the outer surface of the piston and establish it in the support cylinder. Install the dust cover and the piston mounting ring cover. Install covers the guide pin and screw guide pins. Setting Install the brake pads and caliper. Screw banjo bolt brake hose and tighten torque 7-13 Nm.
A WARNING Do not twist the brake hose. |
Fill the brake fluid reservoir. Remove air from the hydraulic system of a drive of brakes. Press the pedal a few times and check for leaks in the brake fluid of the joints. Make sure that when you turn the front wheel from one extreme position to another brake hose is not in contact with the elements of the front suspension and bodywork.
Checking brake disc runout If necessary, replace the brake disc must also be replaced and the second brake disk for maintenance of uniformity of braking. When replacing the brake disc, replace the brake pads. Apply the parking brake, lift the front of the car and fix on supports. Remove a corresponding forward wheel. Remove the caliper mounting bolts, lift the support upwards and secure it with wire. Thoroughly clean the brake disc rust. Disc check for cracks, especially around the holes for the bolts fastening the wheel, as well as deterioration or mechanical damage, if necessary, replace it. Indicator of hour type check up palpation of a brake disk. The indicator of hour type fix in any convenient place and, turning the brake disk, define its palpation at a distance of 5 mm from the outer edge. Maximum permissible palpation - 0.03 mm.
A WARNING In order to secure the brake disc on the hub and tighten wheel nuts. |
The adjustment of the brake disc run-out If the brake disc run-out exceeds the limit, change the position of the brake disc relative to the hub and re-measure the runout of the brake disc. Before moving the brake disc, label side of the chalk wheel and brake disc with a maximum beat.
| Fig. 6.19. Using a dial indicator to measure the backlash front wheel hub
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Remove the brake disc, set the dial gauge as shown in Fig. 6.19, move the hub in the axial direction and measure the play. Maximum permissible clearance - 0.02 mm. If the play exceeds the limit, check each suspension. If the play does not exceed the maximum permissible value, install the brake disc at a position rotated by 180 ?� on the label, and re-measure the runout of the brake disc. If the heartbeat can not be corrected by changing the position of the brake disc, replace the brake disk or process it on a special machine (MAD, DL-8700PF or equivalent). After adjusting the position of the brake disc run-out less often than a new one.
Check the thickness of the brake disc Micrometer, measure the thickness of the brake disc in eight locations approximately every 45 ?� at a distance of 10 mm from the outer edge of the disc. For the true thickness of the brake disk is necessary to take the smallest of the measured values. In the presence of cracks or scratches deeper than 0.5mm brake disc must be replaced. Brake Disc Thickness: - Nominal - 24.5 mm; - The minimum allowed - 22.4 mm. The maximum permissible difference between the thickness of the brake disc - 0.005 mm. If the thickness of the brake disc less than minimum, replace the brake disc. If the difference between the maximum allowable thickness of the brake disc exceeds the limit, replace the brake disk or process it on a special machine (MAD, DL-8700PF or equivalent).
Brake disc while driving on a wet road During prolonged rain opened situated Disc subjected to intensive moisture, which delayed the start of work on the brakes of a second, since first it has to evaporate the moisture, which is between the brake discs and brake pads. In the winter when road salt spreaders, delayed the start of work of brake mechanisms it is much more common, as when braking is first removed salt, located on the brake pads and brake discs. When driving on a wet road is recommended from time to time to press the brake pedal to the brake discs to remove moisture and dirt. Due to the centrifugal force water is discharged from the motion of the brake discs, but they remain a thin film of grease, silicones, rubber residues, grease and dirt, which reduces braking efficiency. When you stop the car after driving in the rain it is recommended to dry the brakes by pressing the brake pedal.
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