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'33 Steering Box
#1
I am sure that aspects of this subject have been done to death over the years, indeed I spent several hours yesterday searching here and through the archive, online and the relevant publications, but I seemed not to find a complete answer, so if I may ask for your help and wisdom I would be grateful for any information, thanks in advance.
A brief resume: My RP in which I have covered about 20,000 miles since 2011, is scruffy but mechanically has had most of its innards fettled, felt or maintained. In 2017 I noticed that steering which always been without wander or twitch, was beginning to get vague and rather stiff away from the centre. It then developed an intermittent-wild-wheel-wobble front offside, so time to deal with it I thought. 
I had the axle ends closed, fitted new king pins, checked the front spring and mounting, renewed the shackles and track rod ends, checked the wheel bearings, rebuilt the drag link and eliminated all but a minimum end play, renewed the ball pins. There was no change, except the steering became a little more stiff away from centre. I removed the steering column and with very able assistance, the inner steering column which was slightly bent was replaced, the old worm was fitted to the new column. The button thrust and the end float on the column were adjusted to a nicety, the play reduced to a minimum and the column reinstalled, with the the wedge washer and brake spindle replaced with new. The steering was even more stiff when on the ground and moving, but free when on the jack. I have checked that the steering arms are not loose. It became uncomfortable, after an hour my shoulders would ache from turning corners. On a jack pushing the wheels from lock to lock is hard one way and impossible the other, with the drag link disconnected the front wheels turn from  side to side without difficulty, so I conclude that it is steering box related.
I decided it was time to try and get to the bottom of the problem. I have stripped the box, which was lubed with Penrite steering box oil, the box has never leaked from either the drop arm felt or the control tube at the bottom. There is no noticeable sign of wear on the worm or wheel, however I have turned the wheel one keyway. I have lapped the worm and wheel together as proscribed. Before I put it back together I have some questions.
I have heard (possibly read but cannot find) that thrust needle roller bearings have been used at, I think, the lower end of the worm, possibly also at the top. Is this a worthwhile modification, if so can anyone direct me to suitable bearings please and perhaps an article or review?
I know about the correct order in which to adjust the three axis, end play, side button play, lastly mesh.
I have part No.BM134 Felt Bush Support, it ls not in good condition and looks like a wavy washer, I dont think it will affect the steering but is there a suitable replacement?
I have always had a difficulty with the steering wheel which seems to go onto the column too far, if the retaining nut is done up tight the recess on the back of the wheel touches the top of the outer column before the wheel is tight against the top of the inner column and cannot be turned, I have to leave the nut just finger tight, which allows the wheel to rock slightly on the splines, what have I missed? Is there a cure?


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Felt bush

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Steering wheel recess

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Support washer, distressed!

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Outer column bearing face, unevenly polished/worn

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Worm top thrust washer evenly polished

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Bottom bearing face with steering box body

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Worm bottom thrust washer, even wear
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#2
Jack, I think you may have in mind a thread on the old forum entitled "steering the beast" dated circa mid June, 2011. Contributions from Rob Beck, John Miles et al.

I doubt that this is your problem but I had an elusive stiff steering problem on one of the specials. The cause was a dent in the upper part of the steering column which pressed on the felt bush. You wouldn't think it mattered but fixing it made a significant difference.

Regards,

Stuart
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#3
If you've adjusted the box up so there is no play in the straight ahead position it will tighten up on lock. If you back off the adjustment so there is about 1" play at the steering wheel rim it should be about right. Same with the column (worm) adjuster on the box. Don't overtighten it. I've done everything you have and have just had to settle for some slop.
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#4
http://pub25.bravenet.com/forum/static/s...4&cmd=show
Refered to earlier, an interesting read.
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#5
Your top felt needs to be oily.
Hope that is helpful.
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#6
There should be no hint of rnon reversability. Due geometric shortcomings, on a weaving surface the wheel will turn back and forth unassisted through an astonishing angle. The steering is heavy at parking speeds (hence for sake of the arm better to get out and pull the wheels around) but not otherwise. Unless very press on I drove one handed to allow. My car at about 130,000 miles and the wheel turned has less than 1/2 inch lost motion straight ahead. With a lapped worm I do not know how these respond if adjustement subsequently slightly altered.
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#7
Hi Jack

Felt seal available here!

https://www.theaustinsevenworkshop.com/p...-bush-9393

Cheers

Howard
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#8
One thing I found when working on A7 steering boxes is that replacing the felt bush at the top of the column with Bronze bush really improved the steering on the road.

I've also had the problem of the steering wheel going too far down the spline, I turned up a thin ring dimensioned on the inside to fit in the groove at the top of the column and dimensioned on the outside to be a snug fit in the steering wheel recess. When this ring is cut in half, both bits can be inserted and you can tighten the wheel against this ring without it binding on the column.
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#9
        Oxford Jack,
I did this and it helped. I also extended the steering arm at the axle to change the ratio to a more manageable one.
Whatever you do setting it up is the important thing.



Paul N-M
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#10
I like that solution. The Bishop Cam steering boxes in Morris 8's as Jack will know as he has one, have a ball cage and track both above and below the worm more or less identical to those found in MG TC's.
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