Rubber-Hydro-Rubber

[111Robin]

This isn't a "pros-cons" thread, more a historical one. What was BMC's take at the time when hydro was introduced and then latterly phased out on the Mini ?. I know it was originally intended for the Mk1 from day one but wasn't ready but when it was introduced, what were BMC saying in the press releases ?. Was it seen as an improvement ?, presumably it would have been lauded as more comfortable, and did they say anything against the rubber suspension that the hydro was replacing ?. Similarly when it was phased out, what were BMC saying to the public ?. Did they just admit to cost cutting or were other "technical" reasons given ?. Was there "public outcry" either when hydro was introduced or when it was phased out ?. I'm not really looking for Autocar/Motor road test performance opinions, more on what BMC were actually saying about the changes at the time. Perhaps the changes passed by with little fanfare but it would be interesting (well........... sort of) to know what BMC were saying about it.

PS. I need to get out more

[Peter Laidler]

You have touched a topic that I have always had half an interest in Rob.

I'm firmly of the opinion that Moulton was a man with a fixation on this fluid suspension system above all others. What you'd call a 'one trick pony. A friend of Issigonis, he presented this liquid transfer system to him as a wonder suspension system. There was really nothing new about it as so it came to pass that the two heads got together and the VERY expensive hydrolastic suspension was put into mini production. At the expense of the far cheaper dry suspension.

As for some of the claims about hydrolastic displacers and the damping abilities are simply mind boggling, even to an average 5th form student studying hydraulics and maths in a school laboratory

How much more expensive in parts, body changes and design engineering has never been disclosed so far as I can ascertain. A quick look at a, say, 1967 parts price list would give a good idea. As for the body changes, production engineers will tell you in no uncertain terms that changes on a production line are a nightmare - as are later modifications. That's because you have already committed to one version and a modification means unpicking the original, which has already been costed AND paid for, for the new. But I digress.

What was VERY good was how lucrative Hydro was for Unipart in sales of hydrolastic parts. Alas....., not so good for BMC / BL with costly hydrolastic failure warranty claims

I have said many times that industry is littered with good ideas like this that are incorporated into production and are found to have no benefits , serving no useful purpose or improvement over what went before. Based on nothing more than fuzzy logic.

Hydro suspension lasted from 196X (?) to 1969. Dry suspension went from 1959 to 2000. The proof of the pudding is in the eating. Or in this case, in the longevity.

[mab01uk]

It is easy to forget that Hydrolastic was fitted to the ADO16 (BMC 1100/1300) for the whole of its production life as a best seller, not to mention the BMC 1800/2200 range, Austin Maxi, etc.
"In Britain, the 1100/1300 series was Britain’s best-selling car every year from 1963 to 1966, and 1968 to 1971. The exceptions were 1967, when the Ford Cortina Mk2 narrowly beat it, and then from 1972 onwards when production of the car was cut by the decision to concentrate assembly at Longbridge. The ADO16 was the nearest Britain got to producing a world car and, in company with the Mini, it represented the high tide of the British motor industry"....and on Hydrolastic suspension.

Alex Moulton’s Hydrolastic suspension debuts
The ADO16 would also be the first BMC car in production with Alex Moulton’s Hydrolastic suspension, which had not been perfected in time for the launch of the Mini in 1959. According to Charles Griffin, Issigonis was not a supporter of Hydrolastic suspension at first. Interviewed by Graham Robson in the October 1997 issue of MINI Magazine, Griffin said of the early stages of Hydrolastic development.
‘The first Hydrolastic types actually had a central fluid chamber – a ‘cheese’ we called it – under the seats, with pipes going in all directions. It was noisy and very harsh – a cat’s eye bump sounded much worse inside the cabin. The next version had displacers at each wheel, but it wasn’t until we put rubber in the suspension linkage that we got rid of the harshness.’
https://www.aronline.co.uk/cars/bmc/110 ... ent-story/

I don't remember that many warranty claims and longevity is proven by the many Hydrolastic Displacers (made by Dunlop) that are still functioning well today, long past their intended lifespan...luckily, as unlike the Mini, most other BMC/BL cars with Hydrolastic suspension have no alternative like the Minis rubber cones....

[mab01uk]

Austin Mini Cooper 998 & Cooper S 1275 1964 Brochure:-
http://www.minipassionmini.50megs.com/p ... 201964.pdf

[111Robin]

That's a good summary on the sales brochure, promoting the hydro as an improvement. So now conversely, what did the brochures state when they went back to dry, or was it just brushed under the carpet with no major announcement ?.
As I said, I'm not getting into the pros and cons, this has been done to death, I'm only interested in how BMC handled the changes , specifically going back to dry. Given all of the other models with hydro (and in particular the sales success with the ADO16), would it not have beenn seen as a step backwards to the customers when they went back to dry and if so how did BMC communicate this to avoid any negative spin ?.

[mab01uk]

As I remember it when BL went back to dry, it was just brushed under the carpet with no major announcement as it coincided with the introduction of the Mk3 range which focused on the new winding windows, etc and not the various cost cutting measures (eg. Hydrolastic to rubber cones) taking place under the BL takeover of BMC, part of the effort to improve the profit margins of Mini production. Some of the new management and staff brought in to implement that process were recruited from the Ford Motor Co. (Note: The ADO16 employed advanced technology to attract buyers, the Ford Cortina employed market research and simple mechanicals to aid reliability and servicing).

For those of us that were 'hands on' Mini owners at the time, the step back to rubber cones was seen as an advantage as you would no longer need to drive to a local garage to get 'pumped up' after DIY suspension work at home when the time came to upgrade from a Mk1 or Mk2 to a later Mk3 Mini, plus you could source newer rubber cone suspension parts off the Mk3 write-off's at the local breakers yard!

The range topping Mk3 Cooper S, 1275GT and Clubman continued on their Hydrolastic suspension for a short time (maybe to use up excess stock?) but notice the 1969 1275GT brochure makes no mention of the fact other than in the small print of the 'Brief Specification'. Also I think as the years went by adverts and marketing of most cars including the Mini and their brochures became less about detailing the technical aspects and moved more towards the lifestyle marketing we see today...where most modern motorists don't even know or care how to change a wheel or open the bonnet.
Mini 1275 GT 1969 - British Leyland:-
http://www.minipassionmini.50megs.com/p ... 201969.pdf

[Ernst Blofeld]

I don’t think it was just Moulton who had a fixation on fluid interconnection. I think Issigonis was just as fixated and I think they were both paying homage to the ideas of Maurice Olley, the GM engineer who Setright tells us undertook the first scientific study of suspension behaviour in the 1930s. Olley was an ex-pat Brit who wound up Stateside as head of Rolls-Royce’s short-lived US operation, and whose work at GM was a huge influence on Issigonis when he was designing the Minor.

From the dim recesses of my memory Olley conceived a formula for a Flat Ride (I’m no engineer, and I am certainly not a mathematician) and it’s this ideal that exercised Moulton and Issigonis and Moulton in the development of Hydrolastic. IIRC there is some mention of this in the Bardsley biography of Issigonis, something along the lines of Olley writing to Issigonis after the launch of ADO16 and saying, “Ah, I see you haven’t forgotten about our discussions about the k formula.”

Also, I am not sure Moulton was a one-trick pony advocating fluid interconnection for everything. Of the automotive suspensions he designed - Flexitor, the Mini’s rubber cone, Hydrolastic, Hydragas, and Telegas - three out of the five featured interconnection. So he may have been an interconnection enthusiast, but surely not a zealot.

[mab01uk]

Also interesting that Moulton was asked to devise self-levelling for the Hydrolastic system back in 1962...

"The estate version of the 1100 appeared in March 1966, marking the end of any serious development of the car. This version was just as stylish and compact as the saloon, but was also a practical load carrier, making it a very appealing package. It carved itself a nice little niche in the market, but was saddled with one significant design flaw: a propensity for the tail to droop markedly under any loading.
Unlike Citroën’s more complex fluid suspension system, the Moulton Hydrolastic design with its front/rear interconnection had no self-levelling capability, and this compromised the car’s competence as a serious load carrier.
Way back in 1962, Moulton has been asked to devise self-levelling for the Hydrolastic system, and came up with an electrically controlled system for the ADO16 – Moulton’s notes show that he thought this would be a good proposition for the ADO16 Traveller. Unfortunately, it was never incorporated in the small car."
Extract from:-
https://www.aronline.co.uk/cars/bmc/110 ... ent-story/

[Polarsilver]

Was Moulton designing his cheaper version of the Citron Hydroneumatic Suspension as fitted to the Citron DS of 1954 .

[Peter Laidler]

The mention of Moultons telegas suspension takes me back. It was another over complicated part of the over complicated Stalwart amphibian system as I recall. Until they were down-graded to simple 6 wheel load carriers, telegas was known to all as TERRORgas!

[111Robin]

Was the Austin 3 Litre the only hydro car that had self levelling suspension ?. I'm guessing it was far too expensive to incorporate into the lower tier cars ?.

[Ernst Blofeld]

The 3-Litre was the only Hydrolastic/Hydragas suspended car with self-levelling.

However, as this piece on the Maxi states, that car had some kind of clever bump stop which was meant to have removed the need for self-levelling. I’m not sure how effective it was…

I hope this link works.

https://driventowrite.com/2019/05/15/12 ... ring-song/

[Costafortune]

Hydrolastic was ultimately a dead end, ditto Hydragas. It worked well but by the 70's there were coil sprung cars like the Alfa Sud that handled superbly yet gave an excellent ride - ditto various Renaults etc. The Allegro was the worst, the first Hydragas car. They never drove properly and the ride was mediocre. The Princess was the best, particularly the second generation after BL farted about with the valving. Even then, the Renault 20 rode just as well on coils. The 1800 was good, the Maxi so-so.

I have to say though - low powered shopping Mini on really good (i.e like new) displacers is so much nicer than a dry one for ordinary use.

[mab01uk]

I have to say though - low powered shopping Mini on really good (i.e like new) displacers is so much nicer than a dry one for ordinary use.

I second that.

[mab01uk]

Wolseley Hornet Mk2 with Hydrolastic Suspension brochure (1965) :-
http://www.minipassionmini.50megs.com/p ... 201965.pdf

[111Robin]

The 3-Litre was the only Hydrolastic/Hydragas suspended car with self-levelling.

However, as this piece on the Maxi states, that car had some kind of clever bump stop which was meant to have removed the need for self-levelling. I’m not sure how effective it was…

I hope this link works.

https://driventowrite.com/2019/05/15/12 ... ring-song/

Thanks, interesting read.

[Costafortune]

Maxis, 1800's and Princesses were redoubtable tow cars.

[Pete]

I’m sure the change back to rubber was something to do with cost and durability but contradicted by the Metro!

[Exminiman]

It surprised me what a fan Issigonis was of Hydro type suspension

According to his biography, Issigonis was playing with Hydro from the mid 50s on the XC /9003 9002 and 9001 prototypes (9003 being the mini) he was obviously really keen on the Hydro concept, right back to his days at Alvis.

As this excerpt from this biography from Gillan Bardsley shows, they had issues with knocking (I think) and Issigonis abandoned Hydro for the launch of 9003 (Mini).

Ironically this was a happy accident as it was the handling that helped promote the car…..It really surprises me that he was so pro Hydro, on a car he was trying to keep costs down on…..but, apparently he was a fan of the Citroen front wheel drive and suspension combination….


.
.

IMG_0523.jpeg

[Ernst Blofeld]

IIRC in the Jonathan Wood biography of the man, Issigonis patented an interconnected suspension system in the 1930s, not hydraulically connected, but using torsion bars.