Steering Box Question

[sfh3l]

Good Morning All.

This is my first post as a new member and thanks for having me.

I have 'inherited' a Seven Ulster Replica from my Dad, still hail and hearty but in his mid eighties and unable to get in and out of the car and to enjoy it.  This is a cheeky little car with a sports engine, built by Pigsty and a beautiful Rod Yates aluminium body. My Dad had this built up from an old Ruby saloon that he had in tea chests for many years.  He hardly used the car once it was finished and it was laid up for around a decade following his knee operation.   I've got the car running nicely, charging and so on, but I have a question:

The steering is unnerving.  The car is very camber sensitive and chases around the road like a dog sniffing out treats.  From what I can see, all is good in the hub area and the drag-link seems ok.  The worst of the play seems to be in the steering box, either in the box itself or on the axis of the drop arm where it emerges from the right hand side of the box.

Looking at various Google images, our steering box seems different from most I can find, but the attached picture of a very special Special shows the kind of box we have.  I should stress the pic is not of my car and our box is mounted much lower down, as per normal, but our box appears identical to this one, hence using the image by way of description.

Can I ask if anyone has and would be prepared to share any instructions for taking up the play in this kind of box please, or indeed if there is anywhere I can purchase a new bush for the drop arm exit, which I think may well be responsible for much of the play?  Failing that, is there anyone who overhauls these boxes commercially please? The steering really is spoiling a fabulous drive.  This car is somewhat older than my other classics (early 70's), but I'd like to be able to enjoy it to its full if I can.

Thanks in advance and what a lovely little forum this is!

Sam.

  Austin Special.jpg (Size: 89.6 KB / Downloads: 555)

[Mike Costigan]

That looks to be a standard steering box as fitted to all Austin Sevens before 1937, when the design was changed.

This link will provide you with comprehensive advice on the standard box:

http://www.austin7.org/Technical%20Artic...0Overhaul/

But before you go mad, do you have previous experience driving Austin Sevens? Most here have been driving them for years, even decades, and it's very easy for us to overlook the dramatic difference between even a well-sorted Seven steering assembly and that of a 'modern' car (by which I mean from the last fifty or sixty years!). The wayward behaviour you describe sounds pretty normal to me!

["Slack Alice" Simon]

See if you can find a standard Austin locally - maybe join one of the clubs - and go for a drive when allowed.

They do hop about.   Check the front shock absorbers are tight enough.   How tight is that?   Tight enough to help the hopping about but not solid.   Ie. I don't know, it is a "feel" thing.

Has it got flattened rear springs?   For a special, they need to be nearly flat or maybe slightly reversed when loaded.

Are all the bits that hold the axles on in good condition?   If the steering box is worn, maybe the front spring shackles and the rear spring pins are worn.

The steering box can be adjusted for play in the mesh, and if the arm moves in or out then some shimming is needed on the little button that takes the end thrust.

Do those two things before worrying about the bearing of the arm itself.

Don't try and take all the play out of the box - the end float in the arm, yes, but not the play in mesh.   No play means it will probably be stiff, and if stiff, you cannot react to the hopping about quickly enough!

[Dave Mann]

What tyres does it have and what pressure are they run at?

[Ivor Hawkins]

In addition to those suggestions, it is critical that you check the caster angle. Your front axle/king pin, should be canted back (top of the king pin closest to the driver) this can have a dramatic effect on the steering on a seven.
Once you’ve checked that, go out for a drive and hold the steering wheel very lightly and don’t try and over correct...they all “sniff about” a bit but they should not take you over the nearest hedge...

[Colin Wilks]

Just for interest, Sam's photo is taken from this listing for a special.

https://ddclassics.com/car-listing/austin-7/

[John Raeburn]

Sam,
Being new to Austin Sevens I am not surprised that you find the steering a bit alarming !
The thing to remember is that you don't  actually steer a Seven, you sort of just aim it in the general direction you would like it to go, and then let it do it's own thing, surprisingly it works!
J

[Howard Wright]

Hi Sam 

From the car and classics photos your front axle is located very well so shouldn’t skip around.  May be the steering box isn’t adjusted correctly?  I would disconnect the drag link (steering side tube in Austin parlance) and see how much play there is on the drop arm.  

The steering box gears do tend to wear In one place (generally in the straight ahead position) however adjusting the mesh should get things tolerable.

I have seen somewhere that the allowable play in a worm gearbox for MOT purposes equates to 3” at the steering wheel.  This always seemed too much to me!

Lovely special by the way! 

Oops realised that this is not your car. In which case check the location of the front axle!

Cheers

Howard

[Robert Leigh]

The type of steering box in the picture is adjustable, as evidenced by the slotted holes in the side through which the drop arm pivots. The internal gear has three keyways so that it can be repositioned when wear becomes a problem. Clearance between the worm and the gear should be adjusted when the wheel is at full lock, checking both extremes, because the centre part of the gear sector in use wears more than the ends. If you do not do this the steering goes stiff in anything but the centre position. With Austin Sevens a little play is preferable to stiffness.
Robert Leigh

["Slack Alice" Simon]

"The internal gear has three keyways so that it can be repositioned when wear becomes a problem"

As indicated in the technical article you get if you follow the link in one of the replies, this is NOT an easy DIY job.

The bloke who wrote the article preferred to re-grind his gears, rather than do it.

If you think you might want to try this, take further advice.

Cheers

Simon