Design of the main gear reducer (models 140 28/032/033 up to 31.05.94, 140.042/043/063/1 and differential diameter 210 mm)
A - Standard version; B - Version with ASR; C - Version with ASD; 11a, 43e, 46b - Tapered roller bearing outer rings; 11b, 43d, 46a - Inner rings of tapered roller bearing; 13 - Differential; 13a, 27a, 56, 56b - Bolts; 25, 42 - Sealing rings; 26, 45, 48 - Gaskets; 27b, 27c, 27d - Bearing caps; 30 - Retaining ring; 31 b - Rings; 33, 33a, 33b - Drive shaft flanges; 40 - Nut; 41, 41a - Drive gear flanges of the gearbox; 43a - Pressure plate; 44 - Bushing; 47 - Drive gear; 47a - Driven gear; 49 - ABS rotor; 50 - Reducer; 54 - Gearbox rear cover; 55 - Sapun; 32, 32a, 70j - Seals; 70l - Hydraulic tube
Disassembly
1. Remove the gearbox (50). Secure it in a vice.
2. Remove the back cover (54).
3. Remove the retaining ring (30) from both drive shaft flanges (33)/(33a)/(33b).
4. Remove the drive shaft flanges.
5. On ASD/ASR models, remove the ball bearings from the flanges.
6. On models without ASD, remove the rings (31b).
7. On models with ASD, remove the hydraulic tube (70l).
8. Remove the bearing caps (27b)/(27c)/(27d), mark them together with the gaskets (260).
9. Remove the differential (13) from the gearbox.
10. Remove the left and right oil seals (32)/(32a), (70j) from the bearing caps.
11. Press both outer bearing races (11a) out of the bearing caps.
12. Press both inner bearing races (11b) out of the bearing caps.
13. Loosen and remove the bolts (13a) securing the driven gear (47a).
14. Carefully remove the driven gear from the differential (13).
15. Loosen and unscrew the nut (40) securing the flange (41)/(41a).
16. Remove flange (41)/(41a).
17. Press out the drive gear (47) from the gearbox.
18. Press out the radial sealing ring (42) from the gearbox.
19. Remove the inner race of the tapered roller bearing (43d) with the pressure plate (43a).
20. Remove the tapered roller bearing outer race (46b), (43e) and gasket (45) from the gearbox.
21. Remove the sleeve (44) with the gasket (48) from the drive gear.
22. Remove the ABS rotor (49) from the drive gear (47).
Examination
1. Check all gearbox parts for wear and replace them if necessary.
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2. Check the drive (47) and driven (47a) gears for correct digital numbering.
Assembly and adjustment
1. Press the inner bearing race (46a) onto the drive gear (47).
2. Press the ABS rotor (49) onto the drive gear (47).
3. Calculate the thickness of the gasket (45) and install it in the gearbox.
4. Install the outer rings (46b), (43e) into the gearbox.
5. Install the bushing (44) with the gasket (48) on both sides of the drive gear.
6. Insert the drive gear (47) into the gearbox (50).
7. Fasten the pressure plate (43a) to the inner ring of the tapered roller bearing (43d).
8. Insert the inner race of the tapered roller bearing (43d) onto the pinion gear and press it in together with the sealing ring (42).
9. Install the flange (41)/(41a) on the drive gear and tighten the nut (40).
10. Adjust the friction torque in the drive gear bearing.
11. Check the adjustment distance of the drive gear.
12. Tighten the nut (40).
13. Secure the driven gear (47a) to the differential (13).
14. Press the tapered roller bearing inner race (11b) onto the differential.
15. Press the tapered roller bearing outer race (11a) onto the differential.
16. Press the seals (32)/(32a), (70j) into the gearbox (50) and insert the differential (13).
17. Install the retaining ring (30) onto the flange.
18. Check and adjust the flange clearance.
19. Attach the cover (54).
20. Replace the breather (55) on the gearbox housing (50).
21. Further assembly and installation are carried out in the reverse order of disassembly and removal.
Technical data:
1. The permissible deviation from the adjustment distance at the end of the drive gear is -0.02/+0.01 mm.
2. The gap between the flange and the gearbox housing is 0.03-0.3 mm.
3. The volume of oil to be filled is 1.3 l.
4. The friction moment in the drive gear bearing is 125-150 Nm.