5.1. Car suspension bracket

POSSIBLE MALFUNCTIONS OF THE SUSPENSION BRACKET, THEIR REASON AND METHODS OF ELIMINATION




Fig. 4.1. Forward suspension bracket of cars of family UAZ-31512: 1 – forward arm;
2 – frame; 3 – buffer; 4 – slip; 5 – shock-absorber arm; 6 – shock-absorber; 7 – back arm; 8 – rubber plugs; 9 – external cheek of an earring; 10 – internal cheek of an earring; 11 – step-ladder; 12 – lining; 13 – spring; 14 – washer; 15 – spring plug; 16 – spring axis


The suspension bracket of the car consists of four longitudinal semielliptical springs working together with hydraulic telescopic shock-absorbers of bilateral action (fig. 4.1, 4.2).
Forward springs of cars of family UAZ-31512 consist of 8 sheets, back – of 7 or 9 sheets depending on a complete set.
Forward and back springs of cars of family UAZ-3741 identical and interchangeable, consist of 13 sheets. Fastening of forward and back springs similar.

Fig. 4.3. Forward spring suspension bracket: 1 – longitudinal bar; 2 – cross draft; 3, 9 – rubber-metal hinges; 4, 5 – arms of a longitudinal bar; 6 – rubber hinges; 7, 8 – nuts; 10, 11 – arms of cross draft; 12 – spring; 13, 14 – spring arms; 15 – vibration-absorbing laying; 16 – stabilizer; 17 – stabilizer arm; 18, 19 – rubber plugs; 20 – step-ladder; 21 – buffer; 22 – shock-absorber


Fig. 4.4. A back suspension bracket with low-laminated springs: 1 – shock-absorber arm; 2 – spring; 3 – shock-absorber; 4 – frame; 5 – slip; 6 – step-ladder; 7 – lining; 8 – earring arm;
9 – shock-absorber arm; 10 – step-ladder nut; 11 – axis; 12 – plug rubber; 13 – buffer; 14 – earring cheek internal; 15 – finger; 16 – earring cheek external; 17 – finger nut


On separate cars of family UAZ-31512 (including on all cars UAZ-3153) the forward spring suspension bracket (fig. 4.3) and a back suspension bracket with low-laminated springs (fig. 4.4) is established.
The low-laminated spring consists of 3 sheets (for the car UAZ-3153 – from 4 sheets).

Fig. 4.5. Shock-absorber: 1 – eye; 2 – compression valve limiter; 3 – compression valve case; 4 – compression valve; 5 – inlet valve; 6 – tank; 7 – cylinder; 8 – return valve; 9 – piston; 10 – perepuskny valve; 11 – rod; 12 – casing; 13 – the directing rod plug; 14 – lower sealing ring; 15 – epiploon; 16 – top sealing ring; 17 – holder of epiploons;
18 – tank nut; 19 – washer; 20 – protective ring; 21 – rod epiploon; 22 – the release buffer (for a spring suspension bracket)



Forward and back shock-absorbers (fig. 4.5) of all cars, except cars with a spring suspension bracket, identical and interchangeable.
At cars with a forward spring suspension bracket and back with low-laminated springs forward shock-absorbers have smaller length (on 25 mm).
On cars shock-absorbers with a diameter of cylinders of 35 and 40 mm can completely be installed. Installation of shock-absorbers of different dimension completely on axes is allowed.

Maintenance
Periodically check a condition of springs, springs of a suspension bracket and shock-absorbers, their fastening and eliminate the revealed malfunctions.
Sheets of springs should not have cracks. The cut of a center bolt of a spring can cause the longitudinal shift of sheets, and weakening of an inhaling of step-ladders – the cross shift of sheets.
For the prevention of corrosion and elimination of a scratch grease sheets of springs as directed of the table of greasing.
Knocks and scratches in ears of springs and hinges of a spring suspension bracket indicate wear or an incomplete inhaling of rubber plugs or wear of rubber-metal hinges. In this case replace hinges and plugs or tighten plugs more densely. For increase in a tightness install in plugs of springs between them rubber laying (rings) which are cut out from the camera or similar rubber.
Sign of malfunction of shock-absorbers is long rocking of the car after moving through roughness of the road.
At service of shock-absorbers periodically examine and in due time tighten their fastening, and also check a condition of rubber plugs in ears.
The shock-absorber during operation of special adjustments does not demand.
You make dismantling of shock-absorbers only in the following cases:
– emergence of not eliminated liquid leak;
– losses of efforts of the shock-absorber at stretching or compression;
– liquid replacements.
Without special need it is not necessary to disassemble the shock-absorber.
Before disassembling the shock-absorber, clear it of dirt, carefully wash out and wipe. Carry out operations of dismantling and the subsequent assembly in the conditions providing full purity.
After the first 3000 km of a run or at dribble of liquid through an epiploon 15 (see fig. 4.5) a rod and sealing rings 14,16 tighten a nut 18. The moment of an inhaling of 78-98 N · m (8–10 kgfs · м). If dribble do not stop, remove the shock-absorber, sort, examine sealing rings and an opening of the directing rod plug 13. Etc. details replace the rod epiploon which is worn out on internal diameter, a rod guide, sealing rings of the tank. 15 establish a rubber epiploon by the inscription "bottom" which is available on it to the piston.
At installation of an epiploon grease its internal surfaces interfaced to a rod with damping liquid for reduction of wear and the prevention of a scratch.
Decrease in efficiency of operation of the shock-absorber or failure can be caused by a contamination of valvate systems, draft of springs of valves or breakage of details. In such cases disassemble the shock-absorber, wash out and replace the sunk or broken springs and details.

Repair
 Removal, dismantling and assembly of springs of cars of family UAZ-31512
You make removal of a forward spring in the following order:
1. Turn off nuts of step-ladders 11 (see fig. 4.1) springs, remove step-ladders, a lining 12 and a slip 4.
2. Establish a forward part of the car on a support.
3. Turn off bolts of fastening of an arm 7 and a nut of axis 16 of an ear of a spring.
4. Remove a spring 13 and sort an earring with rubber plugs 8.
You make installation of a spring upside-down.
You make removal and installation of a back spring similar to a lobby. At installation of forward and back springs on the car the bent ears on the first two sheets have to be turned forward.
You make a final inhaling of nuts of step-ladders of springs at the loaded springs.
You make dismantling of a spring in the following order:
1. Fix a spring in a vice for a head of a center bolt.
2. Unbend collars of springs.
3. Turn off a nut of a center bolt and sort a spring. After dismantling carefully clear sheets of dirt, wash out in kerosene, replace the broken sheets.
You make assembly of a spring upside-down taking into account the following:
1. Before assembly grease sheets of a spring as directed of the table of greasing.
2. Collars reliably to a priklepayta to sheets, end faces of rivets of collars should not act over a surface of sheets.
3. Collars after assembly of a spring should not interfere with free moving of sheets to operating time.
4. After assembly paint a spring.
 Features of dismantling of a forward spring suspension bracket
Replacement of springs 12 (see fig. 4.3), vibration-absorbing laying 15 and buffers 21:
1. Disconnect the lower eyes of shock-absorbers 22 from longitudinal bars 1, having turned off nuts and having taken out bolts.
2. Lift and establish a forward part of the car on a support.
3. Remove springs 12 and vibration-absorbing laying 15.
4. Turn off bolts of fastening of buffers 21.
5. You make assembly upside-down.

Note
At impossibility to take out or insert a spring it is necessary to disconnect in addition one of the ends of cross draft.

Replacement of rubber-metal hinges 3, basic plugs of 6 longitudinal bars and rubber plugs 18, 19 of the stabilizer:
1. Reliably fix the car from spontaneous movement.
2. Disconnect the lower eyes of shock-absorbers from longitudinal bars, having turned off nuts and having taken out bolts.
3. Turn off nuts 7 and beat out bolts of fastening of a longitudinal bar to the bridge.
4. Rasshplintuyte also turn off nuts 8.
5. Turn off nuts of step-ladders of the 20th fastening of the stabilizer to a bar.
6. Remove longitudinal bars, having brought the back end of a bar out of an arm opening on a frame.
7. Turn off bolts of fastening of the stabilizer to an arm 17.
8. Replace rubber-metal hinges 3. Replacement of hinges is made by means of special mandrels on the press equipment. It is necessary to replace at the same time all hinges.
9. Remove plugs 19 from the stabilizer and put on new.
10. Replace plugs 18 and wrap bolts of fastening of the stabilizer to an arm 17.
11. Put on a washer and the basic rubber hinge 6 the back end of a bar 1, insert a bar into an opening of an arm 5, put on the second rubber hinge and a washer, acquire a nut 8.
12. Insert the forward end of a bar into an arm 4, establish new bolts and acquire nuts 7.
13. Similarly establish the second bar.
14. Tighten nuts the 7th moment of 14 - 16 kgfs · m. Tighten against the stop nuts 8 and their zashplintuyta.
15. Establish step-ladders of the 20th fastening of the stabilizer to a bar and tighten nuts of step-ladders.
16. Connect the lower eyes of shock-absorbers to longitudinal bars, having inserted bolts and having wrapped nuts.
 Replacement of cross draft of 2 or rubber-metal hinges 9:
1. Turn off a bolt and a nut of fastening of cross thirst for the bridge and a frame.
2. Remove cross draft.
3. Replace hinges, similar to hinges of longitudinal bars.
4. Establish draft and fix it using new bolts.
5. A nut and a bolt tighten the moment of 14-16 kgfs · m.

Removal, dismantling and assembly of springs of cars of family UAZ-3741
You make removal of springs in the following order:

Fig. 4.2. Forward suspension bracket of cars of family UAZ-3741: 1 – forward arm of a spring; 2 – frame; 3 – spring; 4 – slip; 5 – buffer; 6 – buffer lining; 7 – shock-absorber; 8 – shock-absorber arm; 9 – back arm of a spring; 10 – rubber pillow; 11 – arm cover; 12 – shock-absorber finger; 13 – rubber plugs; 14 – lining; 15 – coupling bolt; 16 – step-ladder; 17 – collars


1. Turn off nuts of step-ladders 16 (see fig. 4.2) springs, remove step-ladders, a lining 14 and a slip 4 springs.
2. Disconnect the lower eye of the shock-absorber.
3. Establish a forward part of the car on a support.
4. Turn off bolts of fastening of covers of arms 1 and 9 and uncover.

Fig. 4.6. The device for installation of springs on family cars UAZ – 3741: 1 – spring; 2 – frame; 3 – lever; 4 – screw holder; 5 – head; 6 – check


5. Remove springs with rubber pillows. You make installation of springs upside-down. At the same time straighten a spring by means of special adaptation (fig. 4.6). In the absence of special adaptation we recommend to make installation of a spring in the following order:
1. Fix springs by step-ladders on the bridge.
2. Establish spring pillows on its ends.
3. Gradually lowering the car on the bridge with springs and directing springs the lever, achieve serial installation of the ends of a spring with pillows in its arms.
4. Establish covers of arms into place and tighten bolts of their fastening.
You make removal and installation of a back spring similar to a lobby.
You make dismantling of a spring in the following order:
1. Fix a spring in a vice for a head of a center bolt.
2. Unbend collars of springs.
3. Turn off a nut of a center bolt and sort a spring. After dismantling carefully clear sheets of dirt, wash out in kerosene, replace the broken sheets.
You make assembly of a spring upside-down taking into account the following:
1. Before assembly grease sheets of a spring as directed of the table of greasing.
2. The selected sheets have to be with the strengthened cups on radical sheets and collars.
3. Collars reliably to a priklepayta to sheets, end faces of rivets of collars should not act over a leaf surface.

Dismantling, assembly and filling of the shock-absorber
You make dismantling of the shock-absorber in the following order:

Fig. 4.7. The key sizes for removal of a nut of the tank of the shock-absorber


1. Fix the shock-absorber for the lower assembly eye in a vice, move the piston to the top situation. Then a key (fig. 4.7) turn off a tank nut.
2. Easy rocking for the top end take out a rod together with the piston from the working cylinder. At the same time be especially attentive not to damage the polished rod surface.
3. Take out the working cylinder from the tank and completely merge damping liquid.
4. Fix a rod in a vice for the top assembly eye, turn off a piston nut. Remove the piston with valvate details, a guide and a holder of an epiploon.
Wash out all details of the shock-absorber in gasoline or kerosene. Carefully examine the washed-out and dried up details and reveal those which are subject to correction or replacement.
At survey of details of valvate knots pay special attention to a condition of valvate edges. In the presence on the locking surface of the valve or its saddle рисок, traces of considerable wear and other defects eliminate them with grinding in. Replace details of valves on which at survey you will find cracks and breaks.
You make assembly of the shock-absorber upside-down taking into account the following:
1. Impregnate a new polyurethane foam epiploon before statement with damping liquid.
2. Establish a rubber epiploon of a rod in a holder so that the inscription "bottom" on it was turned to the piston. Before installation of an epiploon on a rod moisten its internal surfaces interfaced to a rod with damping liquid.
3. Install the working cylinder with the knot of the valve of compression pressed in it in the tank, then fill in damping liquid (320 cm3 – for shock-absorbers with a diameter of cylinder of 35 mm; 345 cm3 – with a diameter of 40 mm; 295 cm3 – for forward shock-absorbers of cars with a spring suspension bracket), at the same time fill the cylinder up to the top, and pour in the rest of liquid in the tank.
Apply damping liquid according to the table of greasing to gas station of shock-absorbers. The amount of the filled-in liquid also has to correspond to the filling volume of the shock-absorber strictly. The admissible difference can make no more than ±5 cm3. Non-compliance with the specified recommendations will lead to violation of operation of the shock-absorber and even its exit out of operation.
4. Insert a rod with the piston into the working cylinder, close the cylinder a guide and then, having accurately straightened a tank epiploon on a guide end face, wrap a tank nut.
Pump over again assembled shock-absorber before statement on the car, moving a rod until the effort does not become constants in all size of the course. It is necessary for removal of air from cavities of the working cylinder.