PREVENTING OIL ON REAR BRAKES

Many Austin Seven owners fmd it difficult to stem the flow of rear axle oil onto their brake linings. Some resort to modern type oil seals and a few even claim success. But by assembling the components with a little care and a little cheating, this problem can he overcome.


1)                      THE FELT OIL SEALS.
The felt oil seals either side of the differential must be greater in width than the "tap hat" containers, otherwise they will not compress against their lids and be hold in place. If this happens, the felt will grip onto the halfshafts instead, and rotate with them. This will cause the felt seals to polish up their containers and allow a good deal of oil through them. It will also enable the flat lids to spin behind the large circlips as they will not he pushed out to make contact. Many circlips have polished flats on them where this has been happening for many years!
Make sure when re-assembling the circlips into the axle cases that they stop the lids of the oil seals from spinning. Most felts that I have bought recently are too thin, so an easy remedy is to buy an extra felt seal and slice off the necessary amount to add to the narrow felt and enable them both to pack into their container and just compress when their lids am fitted. Soak the felt in oil, and when you think they feel right, try them in their containers and slide them over the halfshafts to roughly the positions where they will be. Now by holding their caps on and turning the halfshaft, you will he able to determine if the feats are gripping too tightly onto the halfshafts and rotating with them, or if the halfshafts are spinning nicely inside the felts.


2)                      DRILLING THE AXLE CASINGS
An extra safety device to stop oil creeping down the axle tubes is to drill a 3/32" hole at the lowest point of the axle cases just inside the flange that supports the rear spring pin and bush.
The internal diameter of the axle tubes usually increases at this point, allowing a small reservoir of oil to build up.
There will he times when the oil misses the drain holes altogether and will proceed towards the hubs. This situation may he rectified by pushing a rubber 'c' ring the same diameter as the inside of the axle tube, with some gasket glue around its circumference, to a point a couple of inches down from the outside flange of each axle case. Now any oil which manages to get this far will simply accumulate behind the ring and eventually drip out of the drain hole on the underside of the axle case and help to lubricate your rear spring pin bushes! This modification will also dispose of the rear axle oil that tends to leak around the outside of the oil seals between their containers and the axle cases and by-passes the felts altogether.


3)                      REAR AXLE OIL
I fmd a quarter-pint of Hypoy 140 grade mixed with a quarter- pint of S.T.P. most suitable.


4)                      NOTES
As oil can also leak around the outside of the oil seals it helps to have the gaps in the circlips at the top of the case.
The rubber 'o' ring can be replaced by felt. Ideally, a felt seal located (glued) to the case and making contact with the half shaft would he best. These modifications can only be carried out when the rear axle is dismantled. ie. when the half shafts are not fitted to their casings. Bill Williams thought it unnecessary to drill holes in the rear axle cases, as he assumed most of the oil ran down the half shafts.
An excessive amount of oil will also be allowed to reach the felt differential seals if earlier half shafts are used in conjunction with later differential carriers, which have larger diameter bushes for the half shafts to pass through! - or if the bearing adjusters are not fitted correctly and there is excessive clearance between the half shaft and the scroll-type oil throwers, on their inner surfaces.

 BARRIE ARGENT PWA7C with many thanks.