Excessive play in differential

[Reckless Rat]

ditto. 1/2 pint of SAE 140 should be enough. Refill with the car on axle stands under the chassis and the axle hanging on the springs.

[Tim Hooper]

Okay to both.
Which oil should I use?

[Reckless Rat]

Classic SAE 140. Warm it up before you try to fill as it will flow better (stand the tin in some boiling water). I use a big plastic (100ml) syringe with an clear extension. The two bungs are for draining and filling, but measure how much you put in. You only need half a pint (250ml) as any more will find its way onto the brakes... I save the old stuff for painting the springs and for making home-made waxoyl.

[Bob Culver]

There  is also a taper fixing of the input flange. These are often loose. Perhaps is hammered as many hubs are. On other cars with conventional mitre diff gears impressive backlash often develops at very high mileage but not normally a characteristic of the Austin system. The crownwhhel can be wedged with hard wood through the plug hole which eliminates the planetry dirifferential gears and hubs.

[GaryCullen]

Hi Bob, I sent you a pm..

Gary

[Ian Williams]

How are you testing the backlash?? Are you rotating the propshaft flange and then waiting to see when a wheel starts to turn? If so this will give a false idea of the actual CWP backlash. If you genuinely have 90 degrees of free play in the meshing of the CWP, find out why and fix it or you will, in my experience, have further problems in fairly short order.

[Tim Hooper]

Good morning Ian, I got 90 Deg. Rotation of the prop shaft with the wheels on the ground. I have ordered the oil and manual plus endeavouring to find a local person who might be able to give it a look.

[Renaud]

90 deg. is not tooth play as that's much more than one tooth...

[Bob Culver]

90 deg is two whole pinion teeth so it is not all that. It has been known for cw to come loose, probably also fathomable through the plug hole but would not contribute much. Wedge the cw thru the plug hole and see what then.

[Robert Leigh]

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It is not unknown for the drive flange on the pinion shaft to be loose on its taper, making a big contribution to backlash. Failure of the key giving loss of drive is the expected outcome. All the taper joints in the system, drive flange and hubs must be tight (keys are there to fix the location,they should not provide drive). If there has been play at the drive flange the CWP should be checked for correct mesh as the pinion is not held in the correct location and rapid wear can be expected during the fault period.

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