2. For quick inspection on later models, remove the rubber plugs from the shield and insert a 1.5mm diameter rod into the hole until it is aligned against the brake shoe friction material. If the friction material is worn to the thickness of the rod or less, all four rear brake shoes must be replaced as described below.
Pic. 9.20. Measuring the residual thickness of the brake shoe friction material ('A')
3. To check the rear brakes on earlier models, the wheels and brake drums must be removed.
4. Rear brake drums - integral with rear hubs. Removing the drums requires removing the hub bearings. When installing, the hub bearings must be assembled and adjusted.
5. Very carefully remove brake dust from the brake drum and drum brake shield assembly. Be careful not to inhale brake dust (see Note at the beginning of this Chapter).
6. Measure the thickness of friction material remaining on each brake shoe. If it is worn at any point to the minimum thickness or less, all four rear brake shoes must be replaced.
7. To remove the shoes, first remove the anti-rattle springs, using a pair of pliers to lower each retainer and rotate it 90° (photo); Remove the retainer, spring and spring seat. The anti-rattle pin can be removed if required.
18.7. Press the latch (marked with an arrow) and rotate 90°to release the anti-rattle spring
8. Mark the position of the brake shoes, return springs and handbrake rod. Disconnect the lower return spring (photo). Disconnect the handbrake cable from the grab lever, remove the return spring attached to the cable.
18.8A. Note the location of the brake shoes and lower return spring (early type)...
18.8V....remove the brake shoes from the brake wheel cylinder, then separate the return spring and the automatic slack adjuster struts
9. Gently pull both brake shoes down from the pistons of the service brake cylinder, remove them together with the automatic slack adjustment device stand and the handbrake rod. Do not press the brake pedal until you have assembled the brake.
10. Clean the shield and apply a thin layer of silicone or other high temperature brake lubricant to all contact points between the brake shoes and the shield. Also apply lubricant to the base anchor point, wheel cylinder pistons, and anti-rattle pins and spring seats. If the shoes have not been replaced, check that the handbrake control rod operates correctly.
11. Carefully remove the wheel cylinder dust caps and check for any signs of fluid leakage or other damage. If the brake wheel cylinder needs to be rebuilt, see Chapters 19 and 20 from this Section.
12. To replace brake drums. The stand of the automatic clearance adjustment device is moved forward, the upper return spring is removed, then the safety bracket is removed using a lever.
13. When installing new pads, lubricate the pivot pin with a thin lubricant. Also lightly lubricate the end of the shoe fork and the automatic slack adjustment cable thread, then tighten the nut completely to retract the strut.
14. Be careful not to let lubricant come into contact with the friction material of the brake shoe, assemble both brake shoes, the ALA stand and the upper return spring on the flat surface of the drum, then install the brake slave cylinder. Install the return spring, and connect the cable to the fork lever, then install the lower return spring. Center the entire mechanism within the drum assembly (photo).
18.14. Rear brake shoes (late type, right side)
15. Install anti-vibration pins (if they were removed) then install the springs into the sockets. Clamp the springs with the detents as you install the pins in place, then rotate the detent 90°and release them to lock each assembly into place.
16. Adjust the diameter of the brake shoe to be less than the diameter of the drum to easily install the drum, and install the wheel and apply the handbrake briefly to allow the automatic slack adjuster post to set the correct brake shoe clearance.
17. Repeat the entire procedure on the opposite brake assembly, then check the brake fluid level.
Pic. 9.21. Rear drum brake assembly. Arrows indicate brake lubrication points - see text