1930-1938 Differential Pinion Bearing Puller by John Kaye
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A recent correspondent on the Austin Friends Forum, John Kaye had been removing the Crown Wheel and Pinion from his Ruby with careful reference to The Austin Seven Manual by Doug Woodrow.

"I have followed Woodrow (together with the Austin Seven Companion) and have got the pinion, complete with angular contact bearings in the housing with the flange which connects with the differential casing in the back axle, spacers and roller bearing race still in situ. I have removed the nut and lockwasher (J on Woodrow E5-1) so now I should be ready to follow instruction (2) on Woodrow E5-5. I can't see any way to support the bearings, other than clamping the housing vertically in a vice with the flange resting on the top surface of the jaws. This I have tried, without the vice being clamped any tighter than is necessary just to hold the bearing housing, and then tapped the tapered and threaded end of the pinion, with gradually increasing severity, to no avail."

Following this a number of other forum members suggested they had similar difficulty in getting off the pinion gear end bearings, which unfortunately had to be removed in one go because of the design of the pinion support used by Austin for the 1930 differential.

After some discussion, John turned his mind to a neat solution which took away the brute force often resorted to -

"Thank you all for your collective deliberations on my behalf and all your helpful suggestions. In the event I hatched a cunning plan. I cut a piece of 1/4 inch thick mild steel plate to approximately the same size as the flanges and drilled holes in the corners to take M8 threaded bar, and a hole in the centre to just fit over threaded (forward) part of the pinion. £3.50 at our local hardware store bought four 50cm M8 bars and 16 nuts. These bars were fitted to the flange and nuts tightened either side, and also to the steel plate which was fitted over the end of the pinion. By slowly tightening the nuts behind the steel plate a quarter turn at a time the pinion was pushed out of the bearing housing, leaving the angular contact thrust bearings in situ. These will stay where they for the re-assembly with a new pinion. The outer distance piece and the roller bearing at the end of the shaft right by the bevel gears came out with the pinion but I shall not be re-using these anyway (because of the pinion damage)"

This clever but simple tool is pictured below:

If the pinion support roller bearing (or ball bearing in the early differential) is to be removed as well then another plate could be made similar to the front plate but with a hole to just clear the pinion teeth and the exercise repeated using longer threaded rods.