I have replaced the oil seals on the 1936 rear axle and now need to set the Crown Wheel position relative to the pinion. Woodrow refers to a 0.0002 - 0.0004" preload and a backlash of 0.0004" when the best compromise is reached with the adjusters.

Where and how are these measurements taken please?

All help and suggestions for setting up the rear axle would be very much appreciated.

Check your figures! I'm sure you don't mean 0.0002 (two tenths of a thou!) etc

I set up my D type axle using the Cornwall Clubs excellent reproduction eccentric setting gauge to set the pinion depth. I had previously tried using engineers blue with not much luck due to the parts having 70 odd years of wear on them!! . There is a picture of the gauge in the back of the source book.

With regards to backlash I made an amplifier to turn the 4 thou at the crownwheel/pinion interface into 1/16 inch at the end of the tool. However this was a waste of time with old worn parts because I ended up "tuning" the backlash with the wheels of the ground and top gear selected whilst on stands. You just move the crownwheel sideways using the adjusters until it goes as quite as it can. The actual backlash figure I arrived at I dont know, but several thousand miles later it still works .

If you have just stripped to replace seals then the same shims and a bit of tweaking of the backlash as described should be OK (as long as it was OK before!)

Steve.

Sorry I meant "quiet as it can", NOT "quite as it can"!!!

Thanks! an extra zero has crept in. Figures should read 0.002 - 0.004" and 0.004.

Provided you have not moved the pinion shaft and only want to adjust the crown wheel proceed thus: Slacken the O/S adjuster about 6 slots, tighten the N/S adjuster with a 3 inch piece of 3/16" bar until it is quite tight with finger pressure only. Turn it back two slots and fit the locking plate. Go back to the O/S and tighten the adjuster until tight with finger pressure on the 3-inch bar. Back off one slot and fit the locking plate. Check the backlash on the pinion shaft. If you make up a flat steel pointer with a 90-degree bend on it, you can clamp this to the cardon housing with a jubilee clip, form a point on the end that corresponds to 7 inches from the centre of the pinion shaft. If you have the correct backlash this pointer should only move 1/16” at the point. You will need a helper to hold the crown wheel while you do this, but they must not put any sideways pressure when doing so. If all seems well road test, if noise increases on the drive move the crown wheel to the N/S using both adjusters moved one slot, if the noise is worse on the overrun tighten the N/S adjuster one slot. That will be the best you can do without a strip down.

I have just dug out the pointer mentioned above, it is made from a ½”x 1/8” flat steel strip. A long point is filed on one end. It has a 3/8” long 90 degree bend on the other end. Total distance from point to outside of bend is 5 and 19/32 inches. fix with a jubilee clip to a standard Cardon pot where the oil boot fits on, this will give you the 7 inch centre required for the backlash measurement. I use this when the axle is still fitted to the car. I forgot to mention above, that when you are satisfied you have the optimum position for the crown wheel you can move both adjusting rings towards each other an equal amount to just nip the bearings. The pegs are offset on the plates to give you two positions to choose from.

Many thanks for all the help. I made a pointer as suggested and followed the instructions. It all seems to have gone together without any problems. Thanks again. Hugh.