17.1. Features of a design

Zadny Bridge consists of a beam, a reducer with differential and two half shafts. The main transfer – gipoidny, its gear wheels are picked up for noise and contact therefore it is possible to replace them only in collecting (marking of couple – 2106). The leading gear wheel of the main transfer is executed with shaft (shaft) at the same time and established in a reducer mouth on two conic bearings. External rings of bearings are pressed in mouth nests, and internal — are put on a shaft. Between internal rings the expansion plug is installed; when tightening a nut of a shaft the plug is deformed, providing a constant pretightness of bearings.

The pretightness of bearings is controlled on the moment of a provorachivaniye of the leading gear wheel (other details at the same time are not established). For new bearings the moment of a provorachivaniye has to be within 157–197 N. cm, for bearings after the run of 30 km and more – 39,2–59,0 N. see. At the same time the nut of a shaft is tightened m 118–255 N.' moment, periodically checking a provorachivaniye of the leading gear wheel. If the set provorachivaniye moment is already reached, and the effort of an inhaling of a nut is less than 118 N. of m, it is necessary to replace the expansion plug new as old is deformed too strongly. Replacement of the plug is necessary also in that case when the moment of a provorachivaniye was higher admissible (because of a carelessness at an inhaling).

If the main couple or bearings of the leading gear wheel are replaced, it is necessary to pick up thickness of an adjusting ring anew. It is established on a shaft between the leading gear wheel and an internal ring of the big bearing. The technique of selection of a ring is described in the section Dismantling of a Reducer of the Back Bridge.

The conducted gear wheel of the main transfer fastens to a differential box flange special bolts without washers. These bolts cannot be replaced any other. The box of differential rotates in two conic bearings. Their preliminary tightness, and also a gap between teeths of gear wheels of the main transfer is regulated by the nuts wrapped in demountable beds of bearings. Semi-axial gear wheels are established in cylindrical nests of a box of differential and lean on it through basic washers. These washers are selected on thickness so that the gap between teeths of satellites and semi-axial gear wheels was within 0–0,1 mm. Satellites are installed on an axis with continuous gearing with semi-axial gear wheels. On an axis spiral flutes for a lubricant supply to the rubbing surfaces are executed.

The half shaft one end leans on the single-row ball bearing installed in a nest of a beam of the back bridge, and other (shlitsevy) end enters a semi-axial gear wheel. The internal ring of the bearing is recorded on a half shaft by the locking ring established with a tightness (hot landing). The external ring of the bearing is recorded by a plate which together with a maslootrazhatel and a board of a brake fastens four bolts with nuts to a beam of the back bridge.

In a case of the back bridge fill in 1,3 l of gearbox oil of a class of quality of GL-5 (practically – to the lower edge of a jellied opening). Exits of half shafts from a beam are condensed with epiploons. At leakage of epiploons oil is taken away through a maslootrazhatel outside of a brake board – so it does not get on brake shoes. The epiploon established in a reducer mouth works on a flange surface. Between the bearing and a flange the maslootrazhatel is established. Dribble of oil from under самоконтрящейся indicates nuts of fastening of a flange (the same nut regulates a pretightness of bearings) weakening of its inhaling. Operation of the car with not tightened nut of a reducer can lead to its breakage.

For alignment of pressure outside of and in a case of the back bridge serves сапун, located on a beam of the back bridge over a reducer. At everyone check THAT whether the cap of a sapun is jammed.