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Where should the keyway end up, at the full in our outer end of hub groove on my 22nd series please.

Maybe a photo would clarify what you’re asking. There is no keyway position.

If I understand your question, simply position it to give full engagement to the corresponding keyway slot in the drum hub with none protruding to interfere with the hub-retaining washer and nut.

Bill, you should be abe to see the full "length" of the keyway before you reinstall the brake drum and replace and re-torque the axle nut. If not, something is "wrong".

Bill B

IIRC the key is dressed, or may be dressed to have a curved surface on one side of one end. If your key has such a feature that faces towards inward meaning toward center line of the axle shaft and the toward the differential.

The hub has key way slot that is broached such that the full length is rectangular (constant geometry). The axle was machined with a key cutter, and has a rectangular entry near the axle nut thread. However as the cutter approaches the bearing area the procession of the cutter advancement is paused. This area of the keyway slot will have a circular surface of the same diameter as the cutter.

Take a look at your axle and determine:
1.) Does the axle have such keyway cutter geometry?
2.) Does the key have a ground end that matches the axle geometry?

If you answer ‘yes’ to both questions then of the eight ways the key could be installed only one is correct!

If you don’t have a key with the ground curved surface then you will be required to make one or use a shorter key. The worst thing you can do is attempt to force a square key into the curved portion of the slot, so if you are using a square key make sure the end at the axle nut tread seats properly, and the total length does not allow interference at the radius formed by the cutter. I believe in either case, the key is held captive by the cutter curved surface, and the washer at the nut. If a shorter key is used the captive characteristic is not defeated. Remember if the key is a bit outboard the torque on the rear axle nut will push the key flush to the outboard surface of the hub. If you use a shorter key you might consider putting a slight chamfer on the surface that may contact the curved feature.

I suspect a ‘best practice’ would be install the key and hub and put about 1/2 of the required torque, and then remove the nut and washer and inspect. The key should not be proud to the hub.

dp

Bill B

I re-read your question and have concluded you might have a short key. There’s nothing wrong with that if the shorter length avoids the curved surface in the axle produced by the key cutter. I would test fit the key as far inward (toward the differential) as it can go, but not too far to have an interference fit with the curved surface. Then measure the distance from the key to the shoulder on the axle near the thread. Once you re-assemble the drum/hub you have an appreciation on what the maximum gap might be between the hub and the end of the key.

dp