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Steering box advice
#1
Hi all,

Whilst my front axle was away being overhauled by Alba Austins I decided to overhaul the steering box as it was rather notchy and stiff feeling.  I used the grinding paste method and after about 4 to 5 hrs I managed to grind away most of the high spots but you can still feel them there.  Worried that I was going to 'overwear' the gears I decided to leave it at that.  After thoroughly cleaning, greasing and reassembling the box felt much nicer although slightly tight spots were still evident, I could adjust the box with next to no play and be able to swing it lock to lock without any real issue.
Whilst I had the box apart I adjusted the end float by inserting a shim behind the little button, aiming to have 'barely perceptible play' as described in the manual.

Problem 1

On reassembly I found that the steering became very very tight once everything was bolted in and tightened up.  Eventually I realised this was being caused by the clamp on the dashboard, once I had tightened up the 2 bolts securing the box to the chassis, the steering column would sit a good inch or so below this clamp. Initially I had just pushed it up to meet the clamp and then tightened it, but this seems to be putting enough force on the steering column to tighten on the inner shaft and make the steering horribly tight.  
The only solution I've found to this is to insert a large washer under the rearward bolt of the steering box to angle it slightly upwards, and this puts the steering column in the right place.  I've used a digital inclinometer to measure the chassis, and the part of the chassis underneath the steering box and engine bends upwards about 1.5 - 2 degrees compared to the chassis rearwards, is this normal?  

Problem 2

As I mentioned before, whilst the box was on the bench I adjusted the end float to have 'just barely perceptible play' and all seemed well.  However after fitting the box and connecting everything up etc.  the endfloat now seems excessive...I think I can feel the arm moving in and out at the point when I change direction on the steering wheel and I can see it visibly moving when I rock the offside wheel left to right.
  I'm not sure if I just misjudged the endfloat when checking it on the bench, or if the button wasn't fully seated when I was checking.  Either way I've cocked it up and it will have to come back out again.  
I was wondering if anyone had any recommendations for setting it up properly and getting the best of out the box.  

I should also mention that Ruairidh at Alba Austins is a proper legend.  Does great work and sends you pictures and updates throughout the process (unprompted) and offers brilliant customer support afterwards.  100% would recommend.
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#2
“The chassis bends upwards” doesn’t sound right at all, it should be perfectly straight (but not necessarily level!)

I assume you are using the correct steering box as there were a number of different lengths and angles produced over the years and there is a chance your car may have been fitted with the wrong one.
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#3
The chassis side rails should be straight, but many cars have ben overloaded and abused over their years of existence, and I have seen chassis with a slight sag in their length. With care and persistence straightening is possible using small RSJ sections with spacing blocks and clamps. In practice the side rails need to be pulled marginally past straight because they will spring back when the clamps are released. After doing this correctly I think the steering column will settle in the right place without problem. The only time I did this chassis straightening I also welded square hollow section into the chassis to strengthen it and avoid future problems.
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#4
Thanks Ivor, I will have a look at the box and see what identifying numbers there are on it. I'm new to Austins so wouldn't know by looking. I did notice it has '1927' stamped on, whether that is a date or means something else I don't know.

Robert yes I think perhaps overloading or some abuse is probably the cause (perhaps a previous owner was a bit too fond of the pies...). I'm not sure how serious of an issue it is. If the front end of the chassis is bent upwards slightly it might cause some stress on the propshaft coupling, I will have to have a proper look at that. I'm inclined to just leave it alone as I think straightening chassis rails is a bit above my ability

On the plus side I had the car out the garage for the first time in 2 months today, just for a brief drive around the yard, mostly to boost my morale before I start taking it apart again!
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#5
Chassis straightening is something I would hesitate to do with the body fitted. I should have said that earlier.
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#6
Hi Turboseven

Regarding the shimming adjustment of end float on the arm. One modification that was carried out on my RK was to remove the steel cup. Tap the hole and insert a grub screw and locknut.  Adjustment can then be made without disassembling the box. You can just see this modification on the photo below.  


.jpeg   IMG_0496.jpeg (Size: 94.97 KB / Downloads: 129)

Cheers

Howard
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#7
I was always surprised that on one of our Sevens fitting of the front axle was a bit of a fight, all was revealed during it's rebuild the OS chassis rail was bent which was obvious when the body was off. It was straightened using a borrowed rail cramp from a local railway preservation society and easily done and checked with the body off.    
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#8
Nice one, Dave. The railway approach is never subtle, but effective.

I have a similar adjuster on my steering box, but there is something worth remembering. If you set it up with no free play whatsoever, once you put it all back together the weight of the car will cause things to stiffen up. It's far better to have a little bit of free play at the steering wheel of about 1" at the rim and adapt to an Austin 7s somewhat vague directional acuity. This of course is assuming that everything else is properly adjusted and not worn, eg king pins, radius arms, shackle pins, track rod ends, drag link ball joints and spring bushes.
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#9
(Yesterday, 09:22 AM)Howard Wright Wrote: Hi Turboseven

Regarding the shimming adjustment of end float on the arm. One modification that was carried out on my RK was to remove the steel cup. Tap the hole and insert a grub screw and locknut.  Adjustment can then be made without disassembling the box. You can just see this modification on the photo below.  



Cheers

Howard

I like that
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#10
Some years ago I spent a lot of time adjusting the steering box on my trials 7 such that it had no free play. These were the days when we had to do a 100 mile qualification run on the morning of the VSCC Welsh Trial. As we set off, I realised that no free play meant that I was constantly correcting left and right in an effort to drive in a straight line. It'll wear in over the journey I thought but no, it didn't and it continued the same for the entire weekend. Adding some free play when home solved the problem. I usually aim for 1" at the steering wheel rim equal, roughly, to the distance between two finger grips. Remember, that the UK MOT Tester's Manual says that for a non-rack and pinion (ie steering box) set up and a 'standard' 380mm (15") diameter steering wheel, the maximum free play at the rim is 75mm (3"). Now that does seem a lot.

Steve
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