How to check a steering rack - or just a new one?

[Gary Schulz]

Final product after enameling.

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Unit has been reinstalled and works good as new (maybe better than new). I do recommend that you use a proper pin wrench instead of vice-grips. It makes for a much neater job.

[Spider]

Very fine work there Gary !

[richardACS]

Have to say gents these images and descriptions are most useful. I'm just in the process of overhauling my RHD rack but also completing another which is for my LHD donor parts car - strangely the tensioning part of the rack plunger is completely different between them - the rhd has the spring, the LHD has no central spring. (The LHD is another story as one of the bearing race was found to be broken).

Its the first time I've done this job and external advice was to leave this mk 1 rack well alone as parts are NLA and it seemed to work well without slop or nasty noises. However to complete this rebuild and to ignore it would be to invite unwanted problems and the possible fag in having to drop the subframe in the future. And with all the confidence of the ignorant I stripped the rack apart.

All has gone relatively smoothly with the RHD rack, a new plastic bush, the rack and pinion and the bearings found to be in good condition and therefore with a new pinion oil seal to the ready, the old felt bush was tapped out with Peter L's suggestion of an oversized washer on the end of a long thread and it came out relatively easy and undamaged.

All the parts were cleaned in the ultrasonic tank and the external housing gently cleaned in my blast cabinet where I use a very fine glass media to literally clean almost polish the surface and it all the parts were ready for a final clean and reassembly. In my ignorance however I decided to use a blue lithium greese as opposed to gear oil - I figured it would provide a cleaner situation rather than oil oozing out in the future, but I can see from the comments here that is not good for future wear. I hate to do a job twice, especially as on this occasion I have summonsed all the care, concentration and attention I could muster from the universe.

However after completing the assembly and refitting the shims (that were in place before disassembly), I found the plunger plate locked up the mechanism and I assume this is because the new plastic bush has removed the former compliance of the worn felt bush. I therefore made up some new shims and applied the .002 reduction method and it now seems to have quite a nice smooth 'bench' feel to it.

As I completed the process I had a growing awareness however that I have no idea how this might feel when re assembled in the car with a steering column and a 15" steering wheel fitted! would it be too tight with so no self centreing or too loose once it had the extra loading the steering wheel would provide. There are of course a number of factors to consider: where parts abut each other, the friction from the new plastic bush, the tightness of the pinion between the two roller bearings and of course my use of grease and not gear oil.

Now theres the additional consideration as to whether the rack is central to the outer tube as Gary highlighted. Any how I'm idebted for all the views and experience discussed on this thread and others. I wish I had an accurate lathe to turn up a bronze bush but the one I inherited from my step father while useful for general work has a bit of a slop/wear on the carriage for such a precision peice and in any case it's been a few years since my O level in metalwork.

Steering feel is such an important dynamic and one that when it feels right makes a car a joy to steer. So I will strip this rack down and check out these further issues raised with the expansive knowledge gleaned from here - and yes will re fill with oil this time!

Please send useful vibes via the universe!

[Peter Laidler]

Interestingly, Richard has discovered that there are several variations of the inner end track-rod including the springs and the lock nuts. None of which are interchangeable with the other variations. So if you're doing a few racks, stick the bits in a plastic bag and don't mix them up with parts from other similar - but not the same - racks. Stick with what you've got

Added a bit later by request.... For example, there are track rods with a FULL diameter ball and there's track rods with a large OUTER half ball end with a smaller diameter INNER ball. Plus the different ball cups.

[Spider]

Pete, our Aussie made Racks were quite different to those from the UK and there was a few UK types too, not just the MKI and MKII types, some of the internal parts between the UK racks weren't interchangeable. The UK Racks though, from all the info I have, all had a 13/16" Mainshaft where as our Aussie ones were 7/8". The Ends on ours too, had the 1/2 big, 1/2 small ball ends, with a hardened steel seat, similar to the Mini ball joints.



I am aware that there seems to be quite a few of the Aussie Racks in the UK. They are based on what we fitted to our locally produced ADO16, they just made a shorter version of it. I seem to recall these were a locally designed rack. At the risk of flying the Aussie flag on a UK based forum, I have to say, our Racks were very much better than those from the UK.

[Peter Laidler]

You're right there Chris. I have done a couple of the 'twin-ball' track-rod types as you show. Are these really Aussie made racks? The actual rack ends are machined differently, to accept the diffrerent track rod end cups and springs. I have noticed that there are some hybrid/crossover racks between what we call Mk1 racks and what we call the typical Mk2 'centralised' racks.

Hope that you are well.

Pete the Pom

[Spider]

Yes Pete ! They even had their own Patent No.



Manufactured by TRW. That particular factory was a client of mine up to the time they closed the doors, very sad. They made not only our racks there, but also Ball and Knuckle Joints.

Just looking back through some of my notes, the first series of the UK MKI Racks were similar.

Keeping well thanks mate, but busier than a blue arsed fly atm I owe you an email !

[richardACS]

Pete, our Aussie made Racks were quite different to those from the UK and there was a few UK types too, not just the MKI and MKII types, some of the internal parts between the UK racks weren't interchangeable. The UK Racks though, from all the info I have, all had a 13/16" Mainshaft where as our Aussie ones were 7/8". The Ends on ours too, had the 1/2 big, 1/2 small ball ends, with a hardened steel seat, similar to the Mini ball joints.



I am aware that there seems to be quite a few of the Aussie Racks in the UK. They are based on what we fitted to our locally produced ADO16, they just made a shorter version of it. I seem to recall these were a locally designed rack. At the risk of flying the Aussie flag on a UK based forum, I have to say, our Racks were very much better than those from the UK.

Interesting, my RHD rack is exactly as per your image - likely sourced thinking about it as the car came from New Zealand. Nice to know it's better made!

[Spider]

I am aware that there seems to be quite a few of the Aussie Racks in the UK.

Interesting, my RHD rack is exactly as per your image - likely sourced thinking about it as the car came from New Zealand. Nice to know it's better made!

Ha - there you go.

We did send some cars to NZ, some complete, some CKD and we did also supply parts too. On top of that, there was also the Mokes that were exported to NZ and the UK (and 61 other countries !).

[richardACS]

I have done some research on my car and found it was actually built in the UK for a NZ order, so was shipped immediately after production, the interesting thing was that it was orderd by a Weston Marshall or perhaps Marshall Weston. He apparantly ordered the car with a full compliment of special tuning parts but on arrival found all the ST parts were in boxes and had to be installed and was not best pleased. He owned it for about 6 months (to go racing) but it failed to deliver the results he wanted and sold it on.

I managed to make contact with owners 3 and 6 out of 10 and learned that the car subsequently competed in hill climbs and owner 2 rolled it - so perhaps this damaged the rack and was therefore fitted with an aussie unit. The car was subsequently (years later) discovered by racing driver 'Ken Smith' (quite a local character by all accounts) languishing stripped out in a garage.

I believe Ken Smith also happened to know Weston Marshall (finding the car was a coincidence) but I've been unable to find WM and have been unable to connect with Ken Smith to thow any further light....

[DougR]

Been doing racks lately. Here are my notes. I stripped down types B, C, and D that I had on the shelf. Type D rack is half an inch longer approximately. The outer housings are the same length. The seal is available from Abbey Seals. They do shipping.
https://www.abbeyseals.ie/
+353 1 4277900
Cheers, Doug.

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[DougR]

Mistake in my previous photo. The Mk1 rack has 20 teeth.

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[Peter Laidler]

You have shown exactly why the rack and pinion come as a matched set and should never be changed once mated in place.

The illustration of the Mk2, shown as D shows the pinion with a radial locating/locking groove. In reality, the Mk2 type pinion has a radial slot across the splined part. The lower column bolt ensures that the column to pinion location/fit It is a one position/one way fit.

This is an integral part of the Mk2 type smaller turning circle rack

Pleased to see/read that there was indeed an intermediate/hybrid rack(s) between the true Mk1 and the true Mk2, as explained to me by the former CamGears/Unipart liaison rep some months ago

I'm going to suggest that rebuilding the pinion end without a good helping of mechanical nouse maybe isn't a job for the enthusiastic amateur

[DougR]

Hi Peter, yes I rebuilt it exactly as it came apart with same shims etc. and new seal and it's nice and smooth and without any noticeable play. The only thing I found is that getting the rack into the new vulkolan bush is a bit of an ordeal. Should that be reamed in your opinion? It doesn't mention reaming in the service manual. I noticed that the threads did remove some material from the bush as I was pressing it in. Interestingly the bushes that came out of the B and C types were only half the length of the new bush with a similar half length outer can. See photo. When fitting the new bush I used a full length outer can 37H2079 that I had on the shelf. BTW, you mentioned earlier some modification to allow for more convenient oil topping up. Could you describe this please or point me to a description ? Cheers, Doug.

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