Section D (24/12/08 )

REAR AXLE AND PROP SHAFT

D.1    To remove rear axle from car
D.2    To refit the rear axle
D.3    To dismantle the axle
D.4    To reassemble the axle
D.5    To reassemble the pinion body
D.6    To mesh the crown wheel and pinion
D.7    To replace a rear hub oil seal with axle in the car
D.8    Propeller shaft

 

Sabra Handbook Rear Axle Plate 2

Dl

TO REMOVE REAR AXLE FROM CAR

  1. Jack up the rear of the car and support the chassis on stands, so that the rear wheels are clear of the ground. The rear axle will then be suspended and held by the two check straps.

  2. Remove the rear road wheels.

  3. Disconnect the hydraulic brake hoses and the hand brake flexible cable. Remove the hand brake cross rod by split-pin and clevis disconnection.

  4. Remove bolts and nuts to free the two radius arms from the rear axle tube lugs, at each side.

  5. Remove the four bolts and self-locking nuts from the propeller shaft coupling.

  6. Free the hydraulic suspension units from the rear axle saddles, at each side.

  7. Support the axle at each side, and remove the two check straps from their top brackets. The axle can now be removed. 

D2

TO REFIT THE REAR AXLE

Reverse the above procedure.

 D3

TO DISMANTLE THE AXLE

  1. Remove the level and filler plug and drain plug, to drain rear axle oil. Incline the axle laterally, first one side high then the other, to leave as dry as possible.

  2. Remove the two brake drums by withdrawing the two countersunk screws, at each side.

  3. Remove the rear shaft lock nuts, end washers and hubs.

  4. Remove the four 1/2 U.N.F. nuts, spring washers and brake plates, complete with shoes, from each side.

  5. Take off the rear oil seals, gaskets and bearing retaining plates.

  6. Withdraw the rear half-shafts.

 

Sabra Handbook Rear Axle Pic 02

 
  1. Remove the eight nuts and spring washers from the perimeter flange of the axle plate and knock the two halves apart with a hide mallet. 
    Note that the rear axle tubes are welded to the axle plate and axle case from inside, and can only be freed by turning away the weld seam in a lathe. They are    press fitted and bolt retained in the axle end castings.
    Splitting of the axle case will, in this way, expose the differential case and inner bearing.
    The hand brake cross rod bracket will come free from its mounting to the two rear axle case studs. A vent pipe is fitted to the top of the axle case and can be turned with a pipe grip, to unscrew and remove. There is an additional 3/32' diameter oil breather hole in the left hand axle tube and this should be cleaned out, as necessary.
    There is no gasket between the axle case and axle plate and the spigoted joint is dressed with shellac only, to preserve the oil seal.

  2. Remove the crown wheel assembly complete from the plate, using a pair of levers bearing against the plate to withdraw the crown wheel hub from its bearing.
    Note that there are shims on the crown wheel hub which have been fitted to set the position of the crown wheel in transverse relation to the pinion drive gear. These shims will be either 0-010', 0-005' or 0-003' thick.

  3. Dismantle the planet gear assembly by straightening the end retaining pegs. This will free the differential pin, spur gears and drive shaft gears. The latter are multi-splined in the bore to convey drive to the axle half-shafts, which float in them. The drive shaft gears are backed with brass thrust washers which have concentric oil grooves on each face. The two differential spur gears have brass thrust washers which are crowned, but not grooved. 

  4. Remove the pinion body and dismantle this, if required, by withdrawing the splitpin, castle nut and pinion. To do this, key the coupling flange temporarily to the pinion body with a steel peg through one of the propeller shaft securing holes, so that the nut can be undone. 

  5. Drive the pinion out, using a drift to bear on the end of the pinion gear. 

  6. The inner and outer bearing races, spacers and the pinion end washer can then be removed. Note that shims have been fitted to space pinion bearings correctly. 

 

D4

TO REASSEMBLE THE AXLE

Reverse the dismantling procedure but take note of the following points relating to pinion assembly and meshing of crown wheel and pinion. 

 D5

TO REASSEMBLE THE PINION BODY

  1. Fit the roller bearing inner race by pressing on to the pinion shoulder, just in front of the pinion teeth.

  2. Fit the centre spacing tube.

  3. Replace the shims. These normally aggregate 0-018' total thickness.

  4. Fit the double thrust ball race which has a dual track brass cage, with separate outer races.

  5. Fit the roller bearing, outer race, to the pinion body casting-pressed home on to the spigot seat.

  6. Fit the outer spacing ring.

  7. Insert the assembled pinion aid, using tallow to coat the body sleeve, tap the double ball thrust race down; working around this carefully to ensure true alignment to the sleeve. The pinion will be 'home' when the race is approximately 1/2" proud, above the end of the pinion body casting.

  8. Fit the pinion bearing cover cap with a spring radial rubber oil seal. A shim ring inside the cap will bear on the outer bearing race-0-003', 0-005' or 0-010' thick shims will have been used in original works assembly, as necessary, so that the cap is 0-003' clear of the body, to give positive grip of the assembly when the cap is bolted down.

  9. Coat the cap face with shellac and secure with four 1 1/4 x 7/16 "U.N.F. bolts, and spring washers.

  10. The rear axle coupling flange is then greased and fitted, through the oil sealing ring, on to the pinion spline; followed by a flat washer, castle nut and splitpin. Use the steel peg, previously described, to temporarily key the flange, whilst tightening the nut.

D6

TO MESH THE CROWN WHEEL AND PINION

Check pinion and crown wheel back-lash by to-and-fro hand movement of the coupling flange. Fit the right hand half-shaft temporarily and turn this, listening through the axle-case vent hole, to the sound of the pinion and crown wheel as they rotate, dry. Back-lash should be just perceptible and rotation, as described should not produce any harsh 'chatter' from the gears.

The pinion nut can be re-set either slacker, to let the  pinion IN-, or tighter, to move it OUT.
The crown wheel hubs are shimmed so that variation in these shims and in the IN or OUT setting of the pinion, will determine the mesh of the crown wheel and pinion. 
A visual check of mesh is obtained by coating the crown wheel and pinion teeth with Markers' Blue or with a flat, undercoat paint. Following the hand rotation described, it will be seen that the Markers' Blue or paint has been partially extruded from between the teeth, where they engage, to leave clean metal.
When correct mesh is obtained, this should occur in the centre section of each tooth so that tooth 'heel' and 'toe' marking only is left.

 D7

TO REPLACE A REAR HUB OIL SEAL WITH AXLE IN THE CAR

  1. Jack up the appropriate side.

  2. Remove the road wheel. 

  1. Disconnect handbrake cross-rod clevis.

  2. Remove axle shaft lock nut and washer.

  3. Remove brake drum countersunk screws and drum.

  4. Remove the four 1/2" U.N.F. nuts, spring washers, brake plate and gaskets. The oil seal and bearing retaining plate will follow.

  5. Fit the new oil seal and reverse the above procedure, to reassemble.

 D8

TO REPLACE THE PINION OIL SEAL

  1. Mount the car on a lift platform, or over a pit.

  2. Remove the four propeller shaft bolts and nuts from the axle couple flange.

  3. Centre dot the castle nut and pinion spindle. Remove the split-pin and castle nut and take off the flange.

  4. Remove the four 7/16" U.N.F. bolts and spring washers securing the pinion bearing cover cap. Take off the cap. 

 

Sabra Handbook Rear Axle Pic 03

  1. The cap is fitted with shims and the sprung radial rubber oil sealing ring, in its bore. Press the seal out and replace. 

Reverse the procedure to reassemble, greasing the pinion bearing cover cap to aid bedding on to the bore of the new  oil seal. Re-align the castle nut and spindle centre dots-  see 3 above - to re-set crown wheel and pinion mesh correctly.

D9

PROPELLER SHAFT

  1. Make
    The complete propeller shaft unit is a standard manufacture by Hardy Spicer Limited.

  2. Drive
    There is a front spline-socket which is fitted through the gearbox rear cover cap and radial seal ring, to engage on

the gearbox main shaft. This socket runs in the white metal bush inside the rear cover. Fore and aft movement transmitted from the rear axle is accommodated by the socket splines, which are a slide fit on the gearbox main shaft.

  1. Features
    The propeller shaft has a double yoke universal joint at each end, with the yoke forks pivoting in spring-clip retained needle bearings.

  2. Lubrication, Wear
    There is a grease distributing nipple projecting from each yoke assembly and this distributes grease to the four needle bearings at each end of the propeller shaft.
    A manual check will disclose any side play on spline or yokes, to indicate wear and to assertain need for replacement of bearings or propeller shaft.

  3. Rear Axle Fitting
    The propeller shaft has a rear coupling plate with four holes to accommodate bolts and self-locking nuts, for the transmission of drive to the rear axle differential coupling. 

     

Common Technics