7.8. Brake shoes

Drum brakes of back wheels are regulated automatically. At the same time the press bar under the influence of the adjusting device changes the situation and provides always the constant, structurally caused gap between the brake drum and blocks.

For automatic adjustment the press bar has a carving on which the gear sits. Rotating, the gear changes the provision of a press bar. After single pressing a brake pedal, between the brake drum and brake shoes the gap is provided.

If movement of brake shoes, as a result of wear of brake slips is more, than the provided gap, then a gear, under the influence of the adjusting lever and a spring, is scrolled one tooth further. The provision of a press bar changes – brake shoes are regulated automatically.

Prevention

For removal of springs special pincers best of all are suitable for brake springs, for example, HA2ET 797. It is possible to use as well an alligator wrench.

Removal

Order of removal of springs

PERFORMANCE ORDER
1. To remove the brake drum.
2. To remove a returnable spring (1). To remove a spring (2) of the adjusting lever. Completely to unscrew an adjusting gear of a press bar (3) by means of the screw-driver back. To remove a returnable spring (4) – see rice. Order of removal of springs.
3. To press strongly an alligator wrench a plate of a press spring and to turn on 90 ° (1/4 turn). During pressing to hold a pin from a reverse side of a brake support.
4. To remove the second plate of a spring.
5. To make brake shoes from above a helpless gesture and to take out.
6. To remove the lower returnable springs.
7. To disconnect a rope of the emergency brake.

Installation

Order of installation of springs

PERFORMANCE ORDER
1. To establish brake overlays only of one quality. To clean brake shoes and a brake support. At the removed brake shoes not to squeeze out a brake pedal, otherwise the piston will slip out the brake cylinder. If the brake cylinder crude to touch. To clean a carving of a press bar and to grease. To clean drums with traces of furrows. To pierce always both drums of an axis.
2. To grease with a thin layer of Malykote G6 paste a carving of a press bar, a surface of a prileganiye of brake shoes to a brake support, edges of brake shoes in support and the brake lever on the brake lever.
3. To put on a rope of the emergency brake on a brake shoe.
4. To put on the lower returnable spring and to establish brake shoes on the lower support.
5. To establish from above a press bar with an adjusting gear between brake shoes.
Prevention

The press bar of the left back wheel has the right carving, the right back wheel – left. The bevel of a sleeve and a long pin on a press bar indicate a guard of a brake support.
6. To install brake shoes on the piston of the brake cylinder.
7. To insert pins of press springs behind through brake shoes.
8. To establish press springs. To install plates of springs by the combined pincers and to squeeze a spring, holding at the same time a pin behind (see rice. Order of installation of springs).
9. To turn a plate of a spring on 90 ° (1/4 turns) and to stop.
10. To put on returnable springs in the sequence 4, 2, 1.
11. To make basic adjustment of brakes of a back wheel.
12. To install the brake drum (see subsection 7.7).
13. Repeatedly and strongly to squeeze out a foot brake. It reaches adjustment of brakes of a back wheel.
14. To put a wheel, paying at the same time attention to marking. To remove the car from a trestle and to tighten bolts cross-wise the moment of 160 N · m.
15. To adjust the emergency brake.
16. To check braking at an average speed. If during braking pulls the car aside, to establish the reason and to eliminate (see subsection 7.19).