3.5.1.3. Repair

Dismantling of the back bridge
You carry out dismantling of the bridge in the following order:

Fig. 218. Zadny Bridge: 1 – case; 2 – the gear wheel conducted the main transfer; 3 – gear wheel leading main transfer; 4 – the bearing is back; 5 – the bearing is forward; 6 – ring; 7 – flange; 8 – nut;
9 – washer; 10 – cuff; 11 – the plug is expansion; 12 – the ring is adjusting; 13 – stopper of a bulk opening; 14 – differential bearing; 15 – the half shaft is right; 16 – safety valve;
17 – differential bearing nut; 18 – bolt; 19 – the plate is lock; 20 – the washer is persistent;
21 – case cover; 22 – differential; 23 – bolt; 24 – laying; 25 – the half shaft is left; 26 – the ring is adjusting; 27 – bolt; 28 – differential bearing cover; 29 – maslootgonny ring



Fig. 219. Installation of the bridge at the stand


1. Install the bridge on the stand (fig. 219), turn off traffic jams oil-filling 13 (see fig. 218) and masloslivny openings and merge oil.
2. Turn off bolts of fastening of half shafts and with their help remove half shafts 15 and 25.
3. Turn off bolts 23 fastenings of a cover of 21 cases 1. Remove laying.
4. Turn off a bolt of the 18th fastening of a lock plate 19. Remove a lock plate.
5. Turn off bolts of the 27th fastening of covers of 28 bearings of the 14th differential. Uncover.
6. Weaken a nut of the 17th bearing of differential and take out from a case differential 22 with the conducted gear wheel 2 assembled and bearings 14. Take out an adjusting ring of 26 bearings of differential from a case.
7. Remove the leading gear wheel 3 main transfers.
For this purpose turn off a nut 8 on a shaft, remove a washer 9 and a flange 7, dismantle a cuff 10. Take out the leading gear wheel from a case, pressing from a shaft.
8. Sort differential in the following order:
– turn off bolts of fastening of the conducted gear wheel to a box of satellites; remove the conducted gear wheel;
– turn off bolts of fastening of half of a box of satellites;
– disconnect the right half to-robki satellites from left and take gear wheels of differential, an axis of satellites and persistent washers.

Assessment of technical condition of details
After dismantling of the bridge of a detail carefully wash out in kerosene and examine.
 And vykrashivaniyem on teeths replace gear wheels with teases.

Fig. 220. Removal of the bearing of differential

 
Fig. 221. Removal of the back bearing of the leading gear wheel


Replace the bearings having wear. If bearings and details interfaced to them do not demand replacement, then vypressovku do not carry out rings of bearings. You carry out removal of internal rings (fig. 220) of bearings of differential by devices. Removal of the back bearing of the leading gear wheel is shown in fig. 221. Press off the back bearing only for replacement. When dismantling the bridge internal and external rings of bearings of differential and not a razukomplektovyvayta conducting gear wheels, and at assembly – the bearings which are not subject to replacement establish on former places.
 Flange of the leading gear wheel. The flange end face interfaced to a ring 6 (see fig. 218), has to be smooth. At need to its proshlifuyta to the size on height not less than 53 mm.
 Bridge case. Remove all roughnesses and agnails from landing and adjacent surfaces of a case. Clean oil channels.
 Differentials and half shafts. Replace persistent washers, axes of satellites, satellites, gear wheels of half shafts and a box of satellites with teases and strong wear. Replace satellites and semi-axial gear wheels in a set. Replace a persistent washer of a semi-axial gear wheel if its thickness less than 1,2 mm. At wear of end faces of a box of satellites installation of the washers increased on thickness by 0,1 or 0,2 mm is allowed.
At repair of back and forward bridges use these tab. 15.

Assembly and adjustment of knots of the back bridge
Collect differential in the following order:
1. Before assembly of differential oil transmission gear wheels of half shafts, satellites, persistent washers and axes of satellites.
2. Establish persistent washers on necks of gear wheels of half shafts.
3. Establish a half shaft gear wheel with a persistent washer in collecting in the left box of satellites.
4. Install satellites on an axis of a demountable crosspiece.

Fig. 222. Installation of a demountable crosspiece with satellites in the left box of satellites


5. Establish a demountable crosspiece (fig. 222) with satellites in the left box of satellites.

Fig. 223. Installation of boxes of satellites on tags


6. Establish a half shaft gear wheel with a persistent washer in collecting in the right box of satellites. Holding a half shaft gear wheel, install the right cup of satellites on left so that tags (serial numbers) were combined (fig. 223) of both cups.
7. Connect half bolts and tighten them. Moment of an inhaling of 36-50 N · m (3,6–5,0 kgfs · м).
8. Establish the conducted gear wheel of the main transfer on a box of satellites, having combined openings under bolts. Establish bolts and tighten them. Moment of an inhaling of 100-140 N · m (10–14 kgfs · м).
At collected differential of a gear wheel of half shafts have to be turned by means of a shlitsevy mandrel from the effort no more than 60 N (6 kgfs) enclosed on the radius of 80 mm.

Prevention
Carving surfaces of details and bolts when fastening cups of differential and the conducted gear wheel need to be degreased and applied on them anaerobic TU 6-01-1285-84 UG-6 sealant.

 You carry out assembly and adjustment of bearings of the leading gear wheel in the following order:
1. Pick up adjusting if-tso 12 (see fig. 218) which thickness го is determined by the valid sizes B and G and has to be rav-
on d1= B – (111,960+G) with an accuracy of ±0,025 mm. Establish it in a case of 1 main transfer.
2. Press external rings of bearings of the leading gear wheel in a case mouth.
3. Establish a maslootgonny ring 29 and a napressuyta an internal ring of the back bearing on the leading gear wheel.
4. Insert the leading gear wheel with the bearing and a maslootgonny ring into a case from within.
5. Install the expansion plug 11, an internal ring of the forward bearing and a ring 6 outside on the leading gear wheel.
6. Press aflush a cuff 10 in a case mouth.
7. Establish a flange 7 on vents of the leading gear wheel against the stop.
8. Establish a washer 9 and tighten a nut the 8th moment of 180-250 N · m (18–25 kgfs · l), continuously rotating the leading gear wheel. Check the moment of a provorachivaniye of the leading gear wheel Mv.sh who has to be 1,0–2,0 N · m (0,1–0,2 kgfs · м). Zakernite a nut 8.
 Adjustment of provision of the conducted gear wheel. When replacing gear wheels of the main transfer the provision of the conducted gear wheel is regulated by selection of thickness of a ring 26.

Fig. 224. Measurement of the adjusting size of differential with the bearing


At installation of the new conducted gear wheel 2 and the new bearing 14 installed from the conducted gear wheel and resting against an adjusting ring 26 measure the size E (fig. 224), having made axial effort of P =4000 - 5000 N (400–500 kgfs) and having turned the bearing that rollers reached the correct position. Measure the size B in a case (see fig. 218) from an axis of the leading gear wheel to a persistent end face of the bearing of differential. And the assembly size of 42 mm of the conducted gear wheel pick up a ring for the valid sizes B, E thickness with an accuracy of ±0,025 mm of d2= B – [Е + (42±х)] mm,
where x – the size of maximum deviation from the assembly size of 42 mm with the corresponding sign (plus or minus) which is put with the electrocount at an end face of the conducted gear wheel.

Fig. 225. Measurement of assembly height of the bearing of the leading gear wheel of the main transfer


If it is required to replace only the differential bearing installed from the conducted gear wheel, then it is necessary to measure the assembly height of the bearing as it is specified fig. 225. If the measured height of the new bearing is more or less than height of the old bearing at a certain size, then not to violate the provision of the conducted gear wheel, the new adjusting ring 26 (see fig. 218) has to be thinner in the first case or thickness – in the second at the same size. Then adjust a preliminary tightness of bearings of differential as it is stated above.
Replacement of the bearing of the differential established from an adjusting nut 17 does not influence the provision of the conducted gear wheel, and demands only adjustment of a preliminary tightness of bearings of differential.
 You carry out adjustment of bearings of differential and a side gap (in case of their replacement) in the following order:

Fig. 226. Preliminary napressovka internal rings of bearings of differential


1. Napressuyte internal rings of bearings (fig. 226) of differential on necks of collected differential against the stop.
2. Establish differential in collecting with external rings of bearings of differential in a case.
3. Establish covers 28 (see fig. 218) bearings of differential and fix them by bolts the 27th moment no more than 5,0 N · m (0,5 kgfs · м).
4. You carry out adjustment of bearings of the 14th differential by an inhaling of a nut 17, periodically rotating differential that rollers reached the correct position. After tightening of a nut the total moment of a provorachivaniye of the leading gear wheel and differential has to be in limits Mv.sh of +0,21-0,42 N · m (check carry out a provorachivaniye for the leading gear wheel).
5. You carry out check and adjustment of a side gap in gearing of gear wheels of the established new set of the main transfer after adjustment of their situation.
6. The normal side gap is checked by the indicator in the direction, perpendicular to the surface of tooth of the conducted gear wheel when fixing to an indicator rack case. The gap is checked on 3–4 teeths which are evenly located on a circle. Values of a normal side gap have to be within 0,15–0,25 mm. If the side gap is less, then the picked-up adjusting ring 26 should be replaced with a ring of smaller thickness. During the checking and adjustment of a side gap it is optional to create a preliminary tightness in bearings of differential. There is enough that the adjusting nut 17 was in contact with bearings, and the gap in bearings was absent.
7. After adjustment of a side gap check gearing of gear wheels of the main transfer on a contact spot. For this purpose paint teeths of the conducted gear wheel paint (up to 2 teeth in three or four places evenly on a circle). Then by means of half shafts brake the conducted gear wheel, and the leader rotate in both directions until the contact spot is designated.

Fig. 227. Spot of contact of gear wheels of the main transfer: I – party of the forward course; II – the party of a backing


In fig. 227 typical spots of contact on teeths of the conducted gear wheel of the main transfer are shown at forward and a backing.
The image 1 characterizes the correct contact in gearing of gear wheels when checking under small loading.
At contact on tooth top (the image 2) move the leading gear wheel by conducted, having increased thickness of an adjusting ring, at the same time for preservation of size of a side gap remove the conducted gear wheel from the leader.
At contact at the tooth basis (the image 3) remove the leading gear wheel from conducted, having reduced thickness of an adjusting ring, at the same time for preservation of size of a side gap move the conducted gear wheel to the leader.
At contact on the narrow end of tooth (the image 4) remove the conducted gear wheel from the leader, having reduced thickness of an adjusting ring, at the same time for preservation of size of a side gap move the leading gear wheel by conducted.
At contact on the wide end of tooth (the image 5) move the conducted gear wheel to the leader, having increased thickness of an adjusting ring, at the same time for preservation of size of a side gap remove the leading gear wheel from conducted.
8. Turn off bolts 27 (see fig. 218). Apply anaerobic UG-6 sealant on a carving part, previously having degreased a carving of the connected details, and then tighten bolts. Moment of an inhaling of 140-160 N · m (14–16 ксг · м).
9. Establish on a differential bearing cover a lock plate 19 and fix by a bolt 18, previously degrease a carving of the connected details and apply UG-6 sealant on a carving part of a bolt. Moment of an inhaling of a bolt of 11-25 N · m (1,1–2,5 kgfs · м).
The lock plate can be established in teeths of an adjusting nut by one or two "moustaches". At impossibility of installation of a lock plate in one of provisions tighten an adjusting nut before the next coincidence of teeths.
10. Establish laying 24 covers of a case, a cover of 21 cases and tighten bolts 23. Moment of an inhaling of 11-25 N · m (1,1–2,5 kgfs · м).
11. Having finished assembly of the bridge, about-verte its heating after the movement of the car. If heating of a case in a zone of bearings of the leading gear wheel and bearings of differential over 90 °C (water on a case boils), then adjust a preliminary tightness of bearings as it is stated above.