"Gazelle" Gas-2705>> Transmission>> The back bridge>> Adjustment of the back bridge
Bearings of the back bridge, lateral backlash and position of a stain of contact in gearing of the main pair regulate at factory, and, as a rule, they do not demand adjustment at operation. Their adjustment is necessary only after a partition of the bridge and replacement of details, and also at the big deterioration of bearings. A lateral backlash in gearing of the main transfer, increased owing to deterioration of teeths, adjustment do not reduce, as it leads to infringement of gearing and, as consequence, to the raised noise of the back bridge or breakage of teeths. Люфт in conic bearings eliminate, without breaking mutual position of conducted and leading gear wheels.
Adjustment of a pretightness of bearings of a leading gear wheel
Necessity for adjustment of bearings can be defined on presence axial люфта a leading gear wheel. Axial люфт measure at disconnected карданном a shaft by means of the indicator with the price of division no more than 0,01 mm at flange moving to an axial direction. The indicator leg thus should rest against an end face of a flange in parallel an axis of a leading gear wheel.

Fig. 5.32. The back bridge with a type beam банджо with a separate reducer (an average part): 1 — a nut; 2 — a flange of a leading gear wheel; 3 — a cuff; 4, 6, 11 — bearings; 5 — a ring; 7 — an adjusting ring; 8 — картер a reducer; 9 — a leading gear wheel; 10 — differential; 12 — полуось; 13 — a lining; 14 — a lock plate; 15 — картер; 16 — a nut of bearings of differential; 17 — a cover of the bearing of differential; 18 — a stopper маслозаливного apertures; 19 — a conducted gear wheel; 20 — сапун




The axial backlash in bearings of a leading gear wheel should be eliminated adjustment of a preliminary tightness. A preliminary tightness regulate by selection of a thickness of an adjusting ring 5 (fig. 5.32 see).
Adjustment is necessary for executing as follows:
расшплинтовать and to turn away a nut 1, to remove a flange 2, an epiploon 3 and an internal ring of the bearing 4;
- To replace an adjusting ring 5 new which thickness should be less replaced with size axial люфта plus in addition 0,05 mm at run of the car less than 1000 km or 0,01 mm — at run of the car more than 10 000 km;
- To put into place an internal ring of the bearing, a new epiploon, a flange and to tighten a nut the moment 160—200 Нм (16—20 кгсм) then to check up ease of rotation of a leading gear wheel. If for rotation of a leading gear wheel it is required большее effort, than was before adjustment it is necessary to replace an adjusting ring, having increased its thickness by 0,01—0,02 mm.
After the termination of adjustment of a pretightness of the bearing it is necessary to tighten a nut the moment 160—200 Нм (16—20 кгсм) before cut coincidence in a nut with an aperture under шплинт. The nut for aperture coincidence under шплинт with a nut cut is necessary for tightening only, otherwise because of an insufficient inhaling probably проворачивание an internal ring of the external bearing, deterioration of an adjusting ring and, as consequence, increase axial люфта bearings. At an inhaling of a nut of a flange it is necessary to make проворачивание a leading gear wheel for correct installation of rollers in bearings.
After adjustment it is necessary to check up heating of bearings after movement of the car with a speed of 60-70 km/h within 20—30 minutes Thus mouth heating картера should not exceed 95 With (the water which has got on a mouth, should not boil). At excessive heating it is necessary to reduce a pretightness.
Pretightness adjustment at replacement of bearings of a leading gear wheel and a gear wheel of the main transfer to make in a following order:
- It is necessary to adjust position of a leading gear wheel by selection of an adjusting ring 7 (fig. 5.32 see), having provided the size (109,50,02) mm — distance between the general axis of semiaxial gear wheels and the end face of a leading gear wheel adjoining to an adjusting ring 7;
- Selection of an adjusting ring 5 to adjust a pretightness of bearings of a leading gear wheel. At correct adjustment the moment of resistance to rotation of a leading gear wheel should be in limits 150—200 Нм (15—10 кгссм) for new bearings or 70—100 Нм (7—10 кгссм) for working bearings. If the moment of resistance to rotation of bearings appears within norm, it is necessary зашплинтовать a nut, otherwise it is necessary to repeat adjustment. Thus, if the moment of resistance to rotation has appeared less demanded, it is necessary to reduce a thickness of an adjusting ring and if more — it is necessary to pick up a ring большей thickness.
After adjustment of a pretightness of bearings it is necessary to establish in the bridge differential in gathering and to make adjustment of a pretightness of bearings of differential and a lateral backlash in gearing of gear wheels of the main transfer.
Adjustment of a pretightness of bearings of differential and lateral backlash in gearing of gear wheels and the main transfer
Adjustment without replacement of bearings.
For adjustment of bearings it is necessary:
- To remove semiaxes, a cover картера and a cover lining (for the one-piece back bridge);
- To remove semiaxes and to take out a reducer from картера the bridge (for the back bridge with a type beam банджо);

Fig. 5.33. Check of an axial backlash in differential bearings (the bridge with a type beam банджо)




- At the removed lock plates 14 (fig. 5.32 see) and the weakened covers of 17 bearings of differential adjusting nuts 16 to establish an axial backlash of 0,01 mm in differential bearings (fig. 5.33 see)

Fig. 5.34. Check of a lateral backlash in gearing of teeths of gear wheels of the main transfer (the bridge with a type beam банджо)




- To establish the indicator, as is shown in fig. 5.34, and to check up a lateral backlash in gearing of gear wheels which should be within 0,15—0,25 mm. Check to make in not less than in six points, each time turning a gear wheel;
- To release for increase in a lateral backlash an adjusting nut of from outside conducted gear wheel and on as much grooves to wrap an opposite nut. For reduction of a lateral backlash the specified operations are carried out upside-down;
- To adjust size преднагяга for what to compress bearings in an axial direction:
• on 0,1 mm at run of the car less than 1000 km;
• on 0,05 mm at run more than 10 000 km;
• the control to carry out on an angle of rotation of an adjusting nut. Turn of one nut towards to another for width of a groove corresponds to compression of bearings on 0,05 mm;
- To tighten bolts of fastening of covers of bearings of differential and to check up a lateral backlash of gearings of teeths of gear wheels of the main transfer;
- To fix bolts lock plates on covers of bearings;
- To establish a reducer in картер the bridge;
- To establish semiaxes.
Adjustment at replacement of bearings.
For adjustment of bearings it is necessary:
- To remove semiaxes, a cover картера and a cover lining (for the one-piece back bridge);
- To remove semiaxes and to take out a reducer from картера (for the back bridge with a type beam банджо);
- To remove lock plates 14 (fig. 5.32 see) from covers of 17 bearings of differential;
- To turn away bolts of fastening of covers, to remove covers, to take out differential and adjusting nuts 16;
- To measure by a dynamometer the residual moment of a friction of bearings of a leading gear wheel;
- выпрессовать from a differential box internal rings of bearings and напрессовать the new;
- To put into place differential with new bearings, densely having drawn in their external rings;
- To insert adjusting nuts 16 into a carving part картера the back bridge, is whenever possible closer to bearings, and to establish covers 17 according to available marks on covers of bearings and on картере the back bridge;
- To fix covers of bearings bolts with the effort which is not interfering screwing up of adjusting nuts 16 (apertures in картере under bolts should be preliminary greased анаэробным by hermetic);
- To draw in bearings adjusting nuts before reception of a small pretightness. During time поджатия bearings the conducted gear wheel is necessary for turning on some turns in one, then in other party for correct installation of rollers in bearings;
- Serially tightening adjusting nuts of bearings of differential, to achieve increase in the moment of resistance to rotation of a leading gear wheel on 150—300 Нм (15—30 кгссм) concerning the residual moment of resistance to rotation measured after removal of differential;
- To establish the indicator, as is shown in fig. 5.34, and to check up a lateral backlash in gearing of gear wheels which should be within 0,15—0,25 mm. For backlash increase to release регилировочную a nut of from outside conducted gear wheel and on as much grooves to wrap a nut from outside a leading gear wheel for preservation of a pretightness of bearings. For reduction of a lateral backlash the specified operations are carried out upside-down;
- Rotation of adjusting nuts is necessary for finishing an inhaling. For example, if it is required to release a nut on one groove it is necessary to release it on two, and then on one groove to tighten. It guarantees contact of a nut with an external ring of the bearing and absence of displacement of a ring at work;
- Definitively to tighten bolts of fastening of covers of bearings, to fix bolts lock plates on covers of bearings;
- To establish a lining and a back cover (for the one-piece back bridge);
- To establish a reducer in картер the bridge (for the back bridge with a type beam банджо);
- To establish semiaxes.
Gearing check on a contact stain
After definitive assemblage and adjustment of a reducer of the bridge it is necessary to check up gearing of gear wheels. For this purpose it is necessary to paint teeths a paint. It is necessary to consider that very liquid paint spreads and spoils a surface of teeths, too dense — is not squeezed out of intervals between teeths. Braking a conducted gear wheel, rotate in both directions the leader until the accurate stain of contact will be designated.

Fig. 5.35. A stain of contact of gear wheels of the main transfer: I — the party of a forward course (worker); II — the backing party; 1 — correct contact in gearing of gear wheels of the main transfer at small loading; 2 — contact at tooth top (for correction a leading gear wheel move to conducted); 3 — contact on a fang (for correction a leading gear wheel remove from conducted); 4 — contact on the narrow end of a tooth (for correction remove a conducted gear wheel from the leader; 5 — contact on the wide end of a tooth (for correction a conducted gear wheel move to the leader)




Check of installation of gear wheels and lateral backlash in gearing comes to the end with reception of a correct stain of contact of teeths. The lateral backlash should be within stated limits. On fig. 5.35 typical stains of contact on teeths of a conducted gear wheel of the main transfer of the back bridge are shown.

Fig. 5.36. A correct arrangement of a stain of contact on a conducted gear wheel




The contact stain on both parties of a tooth of a conducted gear wheel should settle down, as is shown in fig. 5.36.
If in the course of adjustment there is a necessity for moving of a leading gear wheel it can be reached change of a thickness of a set of the adjusting linings established between an end face of a gear wheel and an end face of an internal ring of the back bearing of a leading gear wheel.
At change of a lateral backlash the arrangement of a stain of contact changes. Contact in this case moves as follows:
1. For reduction of a lateral backlash the conducted gear wheel moves to the leader, the contact stain on the working (convex) party of a tooth slightly moves more low and more close by the narrow end of a tooth;
2. For increase in a lateral backlash the conducted gear wheel is taken away from the leader:
- On the working party of a tooth the contact stain slightly moves above and more close by the wide end of a tooth;
- On the non-working party of a tooth the contact stain slightly moves above and more close by the wide end of a tooth;
3. At approach of a leading gear wheel to the conducted:
- The contact stain on the working party moves more low and more close by the narrow end of a tooth;
- The contact stain on the non-working party moves more low and more close by the wide end of a tooth;
4. At отодвигании a leading gear wheel from the conducted:
- The contact stain on the working party of a tooth moves to top of a tooth and by its wide end;
- On the non-working party of a tooth the contact stain moves to top of a tooth and moves slightly by its narrow end.