The hand brake is adjusted to reduce the gaps between the pads and the drum, which have increased due to wear of the linings
The presence of large gaps is detected by increasing the travel of the drive lever.
The hand brake is adjusted by the rod 22 and the adjusting lever 17.
Adjustment is made on a cold brake in the following order:
- 1. Disconnect the threaded fork 23 of the drive rod 22 from the lever 30.
- 2. Move lever 30 to the front end position as far as it will go.
- 3. By changing the length of the rod 22 with a threaded fork 23, achieve such a position that after connecting the rod to the lever 30, complete braking occurs when the locking latch is moved by four to six teeth of sector 26, and when the lever 30 returns to the front position, the drum rotates freely without touching the pads brakes.
If the rod shortened to the limit does not provide braking when the locking latch is moved by six teeth of the sector, then you need to move the pin 16, to which the lower end of the rod 18 is attached, to the next hole in the brake adjusting lever 17, securely tighten the nut and cotter.
After that, adjustment should be made in the same way as indicated in paragraphs. 2 and 3.
Caring for the handbrake and drive. Care of the hand brake and drive consists of periodic inspection, cleaning of dirt and checking the fasteners.
If less than 0.5 mm remains from the surface of the brake linings to the heads of the rivets, then the linings need to be changed.
It is necessary to protect the pad linings from getting oil on them, as their frictional properties may change.
The rubbing surfaces of the pivot joints of the brake and drive must be periodically lubricated using a dropper.
In fig. 2 is the size by which the working surface of the brake pads should be processed after installing new friction linings.
The pad diameter (260-0.3 mm) is given for new drums.
After reboring the drum during repair, the diameter of the pads should be equal to the diameter of the drum, respectively.
When processing the overlays between the expanding fist and the pads, it is necessary to clamp the plates 1 with a thickness of 1 ± 0.02 mm, as indicated in fig. 2.
When installing the brake on the surface (D) and resting on the end (T), the runout of the working surface of the brake pads should not exceed 0.2 mm.
After processing the overlays, the plates must be removed.
When disassembling the handbrake, improper removal of the release springs 6 and 12 (Fig. 1) of the pads can lead to breakage of the hooks on them.
The most convenient way to remove the springs is with special tongs that can be made.
If there are no pliers, it is recommended to remove the pads in the following order.
Remove bolt 8 and remove limit washer 9.
Unbend pin 5 and remove it together with the washer.
Then, simultaneously remove the pads from the expander shaft, after which the springs will easily be released.
Install the pads in the reverse order, i.e., hook the springs on the hooks on both pads, push the pads apart and put them on the axle and knuckle, and then fasten.