Peugeot 405 Manual

Rear brake caliper - removal, overhaul and refitting
Braking system / Rear brake caliper - removal, overhaul and refitting

Note: Before starting work, refer to the note at the beginning of Section 2 concerning the dangers of hydraulic fluid, and to the warning at the beginning of Section 4 concerning the dangers of asbestos dust.

Note: New caliper guide pin bolts must be used on refitting.

Note: To avoid the requirement to pre-bleed the caliper before refitting, unless the unit is to be overhauled, do not drain the hydraulic fluid from the caliper - plug the fluid port in the caliper to prevent fluid loss. Peugeot parts dealers will supply new calipers filled with brake fluid.

1 Chock the front wheels, then jack up the rear of the vehicle and support it on axle stands (see УJacking and Vehicle SupportФ).

Remove the appropriate roadwheel.

2 Minimise fluid loss by first removing the master cylinder reservoir cap, and then tightening it down onto a piece of polythene, to obtain an airtight seal. Alternatively, use a brake hose clamp, a G-clamp or a similar tool to clamp the flexible hose.

3 Remove the brake pads (see Section 5).

4 Clean the area around the union, then loosen the fluid hose union nut.

5 Where applicable, prise off the dust cover, then slacken and remove the lower caliper guide pin bolt, using a slim open-ended spanner to prevent the guide pin itself from rotating. Discard the guide pin bolt - a new bolt must be used on refitting. Lift the caliper away from the disc, and unscrew it from the end of the fluid hose. Plug the open ends of the caliper and hose to prevent dirt ingress and fluid loss.

6 The caliper can be overhauled after obtaining the relevant repair kit from a Peugeot dealer. Ensure that the correct repair kit is obtained for the caliper being worked on.

Note the locations of all components to ensure correct refitting, and lubricate the new seals using clean brake fluid. Follow the assembly instructions supplied with the repair kit (see illustration).

11.6 Components of rear caliper
11.6 Components of rear caliper

1 Mounting bracket bolt 2 Bleed screw
3 Handbrake lever spring 4 Caliper body
5 Mounting bracket
6 Guide pin assembly
7 Repair kit

Caliper pre-bleeding
Note: This operation must be carried out whenever the caliper has been overhauled or drained of its fluid, and the operation must be carried out with the caliper removed.

7 With the rear of the vehicle supported on axle stands, and the relevant roadwheel removed, proceed as follows.

8 Reconnect the fluid hose to the caliper, and tighten the union nut.

9 Place a trolley jack beneath the right-hand rear suspension trailing arm, and raise the arm to actuate the rear brake pressure regulating valve (see Section 21).

10 Position the caliper vertically, with the bleed screw uppermost, and keep it in this position throughout the following bleeding operation.

11 Place a block of wood approximately 20.0 mm thick between the caliper piston and the caliper body (ie, in the position normally occupied by the brake pads) to prevent the piston from being ejected.

12 Remove the brake hose clamp or polythene, as applicable, then connect a hose and bottle to the bleed screw, and bleed the caliper using one of the methods described in Section 3 (note that Peugeot recommend that pressure bleeding equipment is used). When the fluid emerging is free from air bubbles, tighten the bleed screw (see illustration).

11.12 Rear caliper ready for pre-bleeding
11.12 Rear caliper ready for pre-bleeding

1 Bleed screw 2 Wooden block

13 Continue to pressurise the hydraulic system (eg, by УpumpingФ the brake pedal) until the caliper piston contacts the block of wood.

14 Open the caliper bleed screw, and remove the block of wood from the caliper.

15 Push the caliper piston fully into the caliper bore. Retract the caliper piston by applying pressure, and turning it clockwise. A special tool is available for this purpose but a pair of circlip pliers or any similar tool can be used instead. Take care not to damage the surface of the piston. Turn the piston to position the notches in the piston on the centreline of the slot in the front of the caliper.

16 Tighten the bleed screw.

17 Refit the block of wood to the caliper, then repeat the procedure described in paragraphs 12 to 17 inclusive.

18 On completion, ensure that the bleed screw is tightened, then disconnect the bleed hose.

19 Lower the trailing arm and remove the trolley jack, then refit the caliper as follows.

Note: Provided that the caliper has not been drained of its fluid, the unit can be refitted as follows. If the caliper has been overhauled or drained for any reason, the pre-bleeding procedure described in the preceding paragraphs must be carried out before refitting.

20 Screw the caliper body fully onto the flexible hose union (if not already done).

21 If the threads of the new guide pin bolts are not already pre-coated with locking compound, apply a suitable locking compound to them.

22 Manoeuvre the caliper into position, and fit the new lower guide pin bolt. Tighten the guide pin bolt to the specified torque, while retaining the guide pin with an open-ended spanner. Where applicable, refit the dust cover to the guide pin bolt.

23 Securely tighten the brake hose union nut (if not already done), then refit the brake pads as described in Section 5.

24 Remove the brake hose clamp or polythene, as applicable, and bleed the hydraulic system as described in Section 2 (if not already done). Note that, providing the precautions described were taken to minimise brake fluid loss, it should only be necessary to bleed the relevant rear brake.

25 Refit the roadwheel, then lower the vehicle to the ground and tighten the roadwheel bolts to the specified torque.

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