Rear Axle Fault Diagnosis; Rear Axle Removal And Refitting; Rear Axle Dismantling And Reassembly; Rear Axle Beam Inspection - Vaz 21213 Repair Manual

Rear axle
The design of the rear axle is shown on fig. 3-54.
Fault diagnosis
Diagnosis
Excessive noise from the rear wheels
1. Loose wheel fastening
2. Worn or failed axle shaft ball
bearing
Constant excessive noise at rear axle operation
1. Deformed rear axle beam,
damaged axle shaft bearings
2. Damaged axle shafts and
intolerable runout
3. Wrong adjustment, damage or
wear of gears or reduction gear
bearings
4. Wear or wrong adjustment of
differential bearings
Noise at acceleration and engine deceleration
1. Wrong adjustment of final
drive gear mesh during reduction
gear repair
2. Damaged axle shaft bearing
3. Insufficient amount of oil
4. Worn gap in final drive gear
mesh during reduction gear
5. Excessive gap in driving gear
bearing due to loose flange fas-
tening nut or worn bearing
Noise at cornering
1. Damaged axle shaft bearings
Knock at the beginning of movement
1. Worn opening in differential
box for differential pinion shaft
2. Loose rear suspension arm
fastening bolt
1. Worn or damaged driving gear
seal
2. Worn axle shaft seal, deter-
mined by excessive oil on braking
plates, drums and pads
3. Loose fastening bolts on rear
axle reduction gear casing, dam-
aged sealings
84
Remedy
1. Tighten wheel securing nuts
2. Inspect axle shaft and replace
bearing
1. Rectify beam and check dimen-
sions, renew axle shaft bearings
2. Straighten axle shafts. In case of
heavy damages - renew
3. Isolate problem and repair reduc-
tion gear
4. Dismantle reduction gear, repair
and adjust
1. Adjust gear mesh
2. Renew bearings
3. Top up oil and check for leaks
from seals and rear axle beam
4. Adjust clearance
5. Check moment of resistance to
rotation, tighten nut or renew dam-
aged parts
1. Renew bearings
1. Replace differential box
2. Tighten bolts
Oil leak
1. Renew oil seal
2. Check axle shaft runout, beam
sag. Straighten or replace damaged
parts
3. Tighten bolts, replace gaskets
Rear axle - removal and refitting
The removal and refitting of the rear axle beam is described
in subsection "Rear suspension". To remove the rear axle it is
enough to disconnect the suspension arm and the shock-
absorbers only from the rear axle beam. When refitting the rear
axle the bar fastening bolts should be tightened according to the
regulations in subsection "Rear suspension". After refitting, bleed
the brakes and adjust the main and handbrake systems as direct-
ed in section "Brakes". Fill the rear axle with transmission oil
through oil fillers.
Rear axle - dismantling and reassembly
Dismantling. Disconnect the pipe ends from the brake cylin-
ders and remove the pipeline with the brake system tee from the
axle.
Place the axle on a repair-bench and drain oil.
After removing the brake drum and undoing the braking plate
fastening nuts with pusher 67.7823.9516 (fig. 3-55), take out the
axle shaft in assembly with the oil screen, the bearing fastening
plate, the bearing and a stop ring. Remove the braking plate and
the sealing ring. If necessary to renew, take out the sealing ring
from the axle beam flange.
Do the same on the other end of the beam, then remove the
reduction gear.
The reassembly of the rear axle is carried out in reverse
sequence:
- grease the threads of the reduction gear fastening bolts with
a sealant, previously having degreased them and the threaded
connections in the rear axle beam;
- grease the axle shaft bearing seal with ãàíéã-24 before
refitting, and use tool A.70157 to refit the seal in the beam flange;
- grease the landing shoulder of the axle shaft and the drum-
mating surface of the flange with graphite or ãëñ-15.
The brake drums are installed after refitting the rear axle on
the vehicle and fastening the cable ends to the handbrake link-
age levers.
Rear axle beam - inspection
Carefully inspect the beam, especially on a vehicle after col-
lision. A damaged beam can become the reason of noise in the
rear axle and quick wear of tyres.
The deformation of the axle beam is checked both horizon-
tally and vertically.
Attach flange A.70172 to each end of the beam, place the
beam with the flanges on identical V-blocks located on a surface
plate with length no less than 1600 mm so that the abutment sur-
face between the casing and the beam will be vertical.