AHM

SECTION H

PROPERLLER SHAFT

Section No. H.1
Description
Section No. H.1
Lubrication
Section No. H.1
Propeller shaft assembly
Section No. H.1
Fault Diagnosis
Fig. H.1. Exploded view of the front end universal joint.
Fig. H.1. Exploded view of the front end universal joint.

I. Flange yoke. 2. Spider. 3. Grease nipple. 4. Needle bearing assembly 5. Snap ring. 6. Spline nipple. 7. Sleeve yoke. 8. Splines. 9. Cork washer. 10. Steel washer. 11. Dust cap.

Section H.1

DESCRIPTION

The propeller shaft and universal joints (Fig. H.1) are of Hardy Spicer manufacture.

The fore and aft movement of the rear axle and other components is allowed for by a sliding spline between the propeller shaft and gearbox unit. Each universal joint consists of a centre spider, four needle roller bearings and two yokes. Reference to the Lubrication Chart (end of Manual) shows the location of the joints.

Section H,2

LUBRICATION

A nipple is fitted to each centre spider for the lubrication of the bearings. Reference to fig. H.2

Fig H.2. Showing oil channels in a joint spider.
Fig H.2. Showing oil channels in a joint spider.

shows that the central lubricant chamber is connected to four reservoirs and to the needle roller bearing assemblies.

The needle roller bearings are filled with lubricant on assembly. A nipple is provided on the sleeve yoke of the sliding spline joint for lubrication of the splines.

If a large amount of grease exudes from the cork seals the joint should be dismantled and new seals fitted. After dismantling, and before reassembly, the inside splines of the sleeve yoke should be smeared liberally with lubricant to Ref. C (page Q.1).

Section H.3

PROPELLER SHAFT ASSEMBLY

Tests for Wear

  1. Wear on the thrust faces is located by testing the lift in the joint, either by hand, or by using a length of wood suitably supported.
  2. Any circumferential movement of the shaft relative to the flange yokes, indicates wear in the needle roller bearings, or the sliding spline.

Removal of Complete Assembly

Before removal of the propeller shaft can be effected, the short length of tunnel immediately to the rear of the gearbox must be removed.

The removal procedure for the propeller shaft is as follows:–

  1. Support the shaft near the sliding joint, then with- draw the bolts from the gearbox companion flange,
  2. Unscrew, by hand, the dust cap at the rear of the sliding joint. Slide the splined sleeve yoke about
Fig. H.3. Tapping the joint to extract bearing.
Fig. H.3. Tapping the joint to extract bearing.

half an inch rearwards, thus disengaging the pilot flanges. (3) Remove the four nuts and bolts securing the rear flange yoke from the axle companion flange and lower the propeller shaft to the ground. (4) The propeller shaft and the two universals can now be taken to the bench for further dismantling.

Dismantling

The following directions apply to both universal joints of the propeller shaft except for the fact that the front joint can be separated from the shaft, whereas the rear joint has one yoke permanently fixed to the tube.

  1. Clean away the enamel from all the snap rings and bearing faces, to ensure easy extraction of the bearings.
  2. Remove the snap rings by pressing together the ends of the rings and extract with a screwdriver, if the ring does not come out easily, tap the bearing face lightly to relieve the pressure against the ring.
  3. Hold the splined end of the shaft in one hand and tap the radius of the yoke with a lead or copper hammer (see fig. H.3, when it will be found that the bearing will begin to emerge. If difficulty is experienced, use a small bar to tap the bearing from the inside, taking care not to damage the race itself, Turn the yoke over and extract the bearing with the fingers (see fig. H.4), being careful not to lose any of the needles.
  4. Repeat this operation for the other bearing, and the splined yoke can be removed from the spider (see fig. H.5).
  5. Using a support and directions as above remove the spider from the other yoke.

Examination and Checking for Wear

After long usage the parts most likely to show signs of wear are the bearing races and the spider journals of the universal joints. Should looseness or stress marks be observed, the assembly should be renewed complete, as no oversize journals or bearings are provided.

It is essential that bearing races are a light drive fit in the yoke trunnions. Should any ovality be apparent in the trunnion bearing holes, new yokes must be fitted.

With reference to wear of the cross holes in a fixed yoke, which is part of the tubular shaft assembly, only in cases of emergency should this be replaced. It should normally be renewed with a complete tubular shaft assembly. The other parts likely to show signs of wear are the splined sleeve yoke, or splined stub shaft. A total of -004 in. circumferential movement, measured on the outside diameter of the spline, should not be exceeded. Should the splined stub shaft require renewing, this must be dealt with in the same way as the fixed yoke, i.e. a replacement tubular shaft assembly fitted.

Reassembly

  1. See that all drilled holes in the journals of the universal joints are cleaned out and filled with lubricant.
  2. Assemble the needle rollers in the bearing races and fill with lubricant to Ref. C (page Q.1). Should difficulty be experienced in assembly, smear the walls of the races with grease to retain the needle rollers in place.
Fig. H.4. Withdrawing bearing cup.
Fig. H.4. Withdrawing bearing cup.
  1. Insert the spider in the flange yoke.
  2. Using a soft-nosed drift about & in. smaller in diameter than the hole in the yoke, tap the bearing in position. It is essential that bearing races are a light drive in the yoke trunnion.
  3. Repeat this operation for the other three bearings. The spider journal shoulders should be coated with shellac prior to fitting the retainers to ensure a good seal.
  4. If the joint appears to bind, tap ’lightly with a wooden mallet which will relieve any pressure of the bearings on the end of the journals. When replacing the sliding joint on the shaft, be sure that the trunnions in the sliding and fixed yoke are in line. This can be checked by observing that arrows marked on the splined sleeve yoke and the splined stub shaft are in line. It is advisable to renew cork washers and washer retainers on spider journals, using a tubular drift.
Fig. H.5. Separating the joint.
Fig. H.5. Separating the joint.

Replacing the Shaft Assembly

  1. Wipe the companion flange and flange yoke faces clean, to ensure that the pilot flange registers properly and the joint faces bed evenly all round.
  2. Insert the bolts, and see that the nuts are tightened evenly all round and are securely locked.
  3. The dust cap must be screwed up by hand as far as possible. The sliding joint is always placeeit towards the front of the car.

Section H.4

FAULT DIAGNOSIS

Possible Fault 1 Shaft bent or misaligned 2 Worn universal joint bearings or spider bearing 3 Sliding joint splines badly worn 4 Loose flange bolts