7.2.1. Maintenance

In use the car it is necessary to make timely tightening of nuts of fastening of wheels to avoid dissecting of fixing openings, to delete a rust from wheels and to produce their subpaint.
For providing the greatest service life of tires it is necessary to be guided by the following rules:
- to support the required pressure in tires. Pressure is checked on cold tires before departure. At stops in way it is necessary to examine tires and to visually control in them air pressure. Not to go with the lowered pressure in tires even on small distances. Not to reduce pressure in the heated-up tires, letting out from them the air as during the movement increase in pressure is inevitable owing to heating of air in them;
- to make balancing of wheels. At the plant of the tire assembled with wheels are balanced dynamically by means of the small weights established on both sides on rim zakraina. Check and balancing of wheels with tires should be made through 12 000 — 20 000 km of a run at the special stand. The admissible residual imbalance from each party of a wheel with the tire should not exceed 40 g on a wheel rim. In case it is not possible to make dynamic balancing of wheels, it is possible to execute static. At the same time balancing small weights should be established on the zakrayena of a rim located closer to the surface of fastening of a disk of a wheel;
- at return to the park and at stops it is necessary to examine tires and to delete from them nails, a wire and other objects. It is necessary to put the car on the pure and dry place. Do not allow hit on tires of oil, gasoline, oil paint;
- at the parking of the car more than 10 days should be put it on supports to unload tires. Do not allow the parking of the car on flat tires;

Fig. 6.14. Scheme of shift of tires

- shift of tires (fig. 6.14) should be made if necessary. Need of obtaining uniform wear of all tires including spare, and also ensuring the correct selection of tires for axes can form the basis for shift of tires. On an axis it is necessary to install the tires having identical wear of a protector, and more reliable tires should be installed on a forward axis of the car.
Limit degree of wear of a protector of a tire corresponds to the residual depth of flutes of 1,6 mm that is determined by measurement or by wear indicators. Wear indicators which height of 1,6 mm, in the form of continuous strips of rubber are located in belts of a protector and are noted on tire sidewalls by the TW1 badges.