Dispose of the displacers?

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rovamota
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Dispose of the displacers?

Post by rovamota » Sun Oct 26, 2014 9:08 am

Hydragas was a clever and simple suspension system and offered supreme ride comfort as well as good handling to many of the cars it was fitted to. That was fine in the '60s and '70s but technology has moved on and many modern cars simply ride far better with standard springs and dampers than anything that could be achieved by Hydragas.

With yet another front displacer failing on my Wedge for the second time this year I think the lack of displacers is already an issue and in years to come will ultimately lead to cars being unusable because of it. The trouble with Hydragas is that it just fails without warning and unlike a car with a worn shock absorber or spring the car is completely unusable until it is replaced.

Regassing the nitrogen has recently been an option, which is fine but it doesn't replace worn components in the unit itself and there is no guarantee it will last another 3 years let alone 30, and eventually it will blow. And a blown displacer can't be repaired by anyone.

The MG F range also runs on Hydragas suspension but with the earliest cars now reaching 20 years old it became apparent that there simply aren't enough displacers in the world to keep the cars on the road, so a kit has been made available to ditch the Hydragas and convert it to a much more reliable spring/damper system. This is explained here http://www.the-t-bar.com/forum/54-how-t ... us-version

As you can see it's quite an impressive set up though it would need modifying for the Princess; the spring and damper would need to be incorporated as a single unit.

We need someone who knows about elastokinomatics and can suggest a suitable spring/damper ratio for the Wedge, and then we could go about getting them manufactured. But obviously this would cost a fortune and a complete new suspension could easily cost £1000 per car, but if it meant keeping your Wedge on the road then surely it would be the best money you ever spent on your Wedge.

So, who wants a project?
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Re: Dispose of the displacers?

Post by Dave » Sun Oct 26, 2014 11:09 am

That is a very elegant solution - it is more feasible than the coilover design. It suits the MGF better as the shockers fit more naturally. I particularly like the ride height adjustment feature.
For this to work on the Princess, mountings for the dampers/shockers would have to be added to the cars structure and suspension - not impossible as I fitted a telescopic damper kit to an MGB and the mounting points used existing suspension parts with simple adaptor plates.
As an ex machinist - the housing components are relatively simple to make and as Kev says it just needs a spring of the right tension to suit the wedges weight.
There is plenty of space for a damper at the front but the rear would be a challenge - maybe a boot floor top mount and a downward extended carrier bolted to the radius arm :idea:
Some points to ponder though - the DVLA say there are only 29 princesses left, don't know how many Ambos but say a dozen. There are probably enough displacers around, including from scrappers yet to relinquish them, to last our current "fleet" for many years.
Also talking to my local MG man at Summit Motors in Maidenhead, he says he has stocked the MGF hydragas replacement kits since about 2009 but has never sold any :shock:
Finally, Landcrabs and the Austin 3 litre still soldier with albeit hydrolastic displacers and they have a few years on our cars 8-)

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Re: Dispose of the displacers?

Post by Peter Laursen » Mon Oct 27, 2014 8:31 am

Just an idea: Would it be possible to use the same setup as used for the Mini, i.e. rubber cones and telescopic dampers? It would of course need suitable cones can be manufactured.
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Re: Dispose of the displacers?

Post by Gasman » Mon Oct 27, 2014 9:20 am

Ah, hadn't seen this and have just posted a similar topic thread under 'Welcome' as a new forum member is Alexander Boucke who has re-gassed a set of displacers for me (although I've not fitted them yet). I have posed a similar question to him so I'll be interested in his views.
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Re: Dispose of the displacers?

Post by Vulgalour » Mon Oct 27, 2014 3:44 pm

I'm still trying to find someone willing and able to dismantle a displacer and see if repair/remanufacture is an option. Most don't even want to consider doing it which is fair enough as we are a very tiny market that isn't very profitable to cater to.

There are two other options I've found that would be viable. The first is to modify the Citroen hydropnuematic system as practically all the parts, including spheres and LHM reservoirs, are easy to obtain brand new for not very much outlay. There's a strong Citroen following so it's unlikely that parts would dry up and it will give a similar ride to the original Hydragas. It is a lot of work to modify to fit the car though and there are various things that would need to be considered to make it a viable replacement.

The other option, which retails at around the £1200-2000 mark is custom hydraulics. You don't need to make a Princess dance, and it would be unwise to try it without serious modification, but you can fit airbags and hydraulics without compromising the functionality of the car itself. All the parts are brand new, the market in America is vast for this and it gives a smooth comfortable ride with the option to adjust ride height.

Of the options available to me, I hope to be able to afford full hydraulics. I'll lose some boot space and a good chunk of pocket money but it really is the most sensible way to go at the moment.

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Re: Dispose of the displacers?

Post by threelitre » Fri Oct 31, 2014 11:58 pm

The very short answer to Kev's question raised in the title: No!

For me Hydragas is one of the defining mechanical features of these cars (well, for me it is a pair of Maxis), and although there are possible replacements, none of them can offer the same combination of features that Hydragas offers. Which does not say that other systems are not good, they just cannot offer the same characteristics.

More in a long answer, but prefer to type that in a proper editor and publish it here later...

Regards,

Alexander

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Re: Dispose of the displacers?

Post by threelitre » Sat Nov 01, 2014 1:23 am

The future of Hydragas suspension

All owners of Hydragas-sprung cars certainly know the big advantages these suspensions give to the ride and handling of the cars. But many will by now also know the downside. Due to the age of the systems, failures of spring units start to get more often. Loss of Nitrogen is one of them, rupture of internal or external diaphragm is another one.

Keep it or replace it?

It cannot be denied that modern standard steel spring and damper suspension have come a long way since the 60s and do work very well. And computations can help to adjust the rates close to getting perfect even before the first test drive. With this in mind, the question should be allowed, if a replacement made of standard springs and dampers cannot be made. Of course this is possible and has already been done to my knowledge to at least one 1300 and one Austin Allegro. And there are – of course – kits available to replace the rubber springs in Minis and Hydragas on the MGF. But this requires quite a bit of effort and specifically made parts, so it will be quite expensive.

On the other hand the ride experienced with Hydrolastic and Hydragas cannot be replicated with a conventional setup. The reason is, that both spring rates and damping rates are highly progressive, both increasing with the load of the car in a way that the car 'feels' roughly the same, independent of the load. And this is before getting the interconnection of the units on each side into play. Today similar effects are achieved using very sophisticated computerised adaptive damping and anti-roll systems or air-suspension struts where the air-pressure in the springs also controls damping rates (and makes it the only other suspension to achieve the same indepentence towards loads as Hydragas and Hydrolastic).

Let's have a look at the possible replacements:

Steel springs and traditional dampers: In terms of adapting them to a small run these are by far the easiest for both calculation of needed spring and damping rates as well as manufacture. If there should be no large modifications to the bodywork, these springs need to go into the place of the original spring units including the damper like a classic coil-over system. The problem is, that it is very unlikely that there is any off-the shelf component to be applicable, as the large transmission ratio of 1:4 means that these ultra compact springs would need to carry a huge load. This would make it very difficult to introduce a proper progression into the springs – something both kits for Mini and MGF suffer from as far as I am aware. The dampers will pose an additional problem: The need for very compact size combined with a very high damping rate may also lead to a temperature problem combined with premature wear compared to a more traditional setup. The inner wings of all cars with Hydragas are not designed to take up the forces of either springs or dampers, so to fit more conventional struts a redesign of at least the front structure of the car is needed. If the handling should not be compromised the ´hard´ mode of Hydragas, as in cornering when interconnection is not active, should be used as a base-line for spring rates.

Hydropneumatic suspension (Citroën): Due to the high pressures used in this system it will be prohibitive from a cost point to have any parts apart from connection pipes specifically made for the conversion. Struts are of a fixed size that needs to find a space, and although compact the need more space than Hydragas units. There are struts suitable to high leverage suspensions in the early Citroën models, namely DS/ID, GS/GSA, SM and CX. The spring rates of Hydropneumatic suspension are indeed progressive (relying on the correct amount of gas in the spheres), but it fails to deliver a progressive damping due to the cylindric displacers – as opposed to cone shaped on Hydragas. Whilst the shape of the Hydragas displacers does define the ride height of the car as a relation between pressure and car weight, the cylindric displacers of Hydropneumatic cannot do this. So Hydropneumatic does not work without front and rear height regulators, a pump, a pressure switch and an accumulator. Changes to the bodywork to accommodate the struts and the added complexity of the system needed will make it very involving to fit. Add parts supply problems and a very different ride characteristic – not a change I would personally be happy to work on. Although I have to say that a well sorted Hydractive (that is electronically controlled for stiffness and damping) sprung Citroën XM is as close as you can get to an old Austin 3 litre in terms of how it feels.

Air-springs: There seems to be a lot of promise in these, but as they are typically designed to either replace a conventional strut or have spring and damper in different locations the changes to the bodywork needed will be substantial

Of cource I do not want to stop anyone pursuing one of these solutions, but they do rob the car a significant part of its identity and are neither cheap nor easy to implement.

Future of Hydragas

The late Dr. Alex Moulton was well aware of the problems owners of cars with 'his' suspension system may have in the future. During a couple of meetings over the past 10 years he has shown me a possible solution, reaching far further than the simple re-charging of the spheres with Nitrogen.

The re-charging is still a very important step in both keeping the cars in a condition to use or enjoy them, but it also is essential to prolong the life of the Hydragas units.

Regardless of the state of the sphere, the internal diaphragm will always be free of any significant forces, as the pressures on both sides will always be the same as long as there is any amount of Nitrogen left. There is a danger for the diaphragm though when the amount Nitrogen gets very low and the remaining gas cushion gets ever more shallow due to the car being pumped up ever again to keep the ride height correct. At a certain point it cannot be avoided that the diaphragm contacts the rivet that closes the top of the sphere, which may be relatively sharp edged and thus may damage the diaphragm. I do think that most failures of the internal diaphragm are due to the owners keeping the car at the correct ride height with only a marginal amount of Nitrogen remaining. When the car starts to get firm it is safer for the units to actually let the car drop in ride height and not keep it topped up (making it even more uncomfortable to drive, which I know from painful experience!).

From Citroën it is known that regularly re-charged spheres do have a very long life. Also the highly loaded lower diaphragms on Hydrolastic cars are now holding up well at an age of 40-50 years. It is relatively safe to assume that the internal Diaphragms of Hydragas units will have a very long life if the units will be kept sufficiently filled with Nitrogen.

If for any reason the need arises to open the units and have the rubber components replaced, Dr. Alex Moulton developed a concept to close Hydrolastic units again and tested it. Everything considered, the rubber parts may be relative cheap to remanufacture, the metal casings will be very expensive (prohibitive in fact). So the idea of carefully opening, fitting new rubber parts and closing them again does not seem to be unrealistic to me.

Dr. Alex Moulton has put some thought into this issue and came up with a solution that he tried and successfully tested on a Hydrolastic unit. Just as the two flanges on Hydragas units, where the three main parts are pressed together and then the flange is rolled, so that it seals the connection, Hydrolastic units a made by 3 pressed parts, connected by a single rolled flange. When carefully cutting this flange, the unit can be opened.

Dr. Moulton came up with a solution how to close the units again. Three rings where manufactured, practically creating a kind of compression fitting held together with a large captive nut in the place where the original joint was. The ring around the spring unit needs to be split in halves to be able to be fitted, whilst the other ring and the captive nut can be slid over the unit from the displacer end. Tightening these should be done in a hydraulic press similar to the original process. Dr. Moulton actually has had a prototype made and put it into a test bed to check the unit after refitting successfully.

Hydragas units have two of these joints and the fittings needed would need to be designed. A problem that should well have a solution. The design also will need to take care of the dimensions of the fitting space inside the cars. A further problem is caused by the mounting arrangement on the rear for Princess and Allegro cars, which will either need to be modified to take the complete displacer as a removable unit or be considered to be part of the process or re-sealing the units.

If this process is properly executed and costs are shared between Maxi, Princess, Ambassador and Allegro owners (using the same sizes of units), it should be a much cheaper alternative to a change to a completely different system – and – more importantly – should keep the cars as characterful as they are.

Do I need to say that the clubs or individuals should try to keep as many units in store as possible - even the broken ones?

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Re: Dispose of the displacers?

Post by rovamota » Tue Nov 04, 2014 7:16 pm

Alex, that is a very elegant and constructive response.

I agree that removing the Hydragas system would take away some of the character of the car and possibly its second best feature (the styling being the first).

But we are still left with a situation where there is currently no alternative to fitting an old stock or used displacer of unknown origin. As you say, perhaps all of the clubs that support Hydragas suspended cars should get together to seek a solution, but it costs money, money that none of the clubs at our level have to spend frivolously on suspension development or reproduction even it does mean keeping our cars on the road.

However, if I ever win the lottery I would invest in such a project.
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Re: Dispose of the displacers?

Post by beiderbecke » Tue Nov 04, 2014 7:31 pm

:!: Haven't we enough in the club funds to cover this?

Perhaps the answer is to take out the innards of the displacers and insert a coil over... :roll:

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Re: Dispose of the displacers?

Post by rovamota » Tue Nov 04, 2014 7:33 pm

Will 10s 5d be enough?
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Re: Dispose of the displacers?

Post by beiderbecke » Tue Nov 04, 2014 8:33 pm

:lol: Not quite, but I've got some Green Shield stamps and a '70's petrol coupon booklet...

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Re: Dispose of the displacers?

Post by steveb » Tue Nov 04, 2014 9:38 pm

Do we know if any of the other clubs have found a way round this problem, i'm thinking the 1100 had hydrolastic suspension in the '60s. the displacers on these must be failing ?

The NEC might be the place to see if anyone can possibly offer a solution
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Re: Dispose of the displacers?

Post by Gasman » Wed Nov 05, 2014 8:16 am

My impression is that there seem to be less problem with hydrolastic displacers as opposed to hydragas ones despite the fact that they are generally much older. Firstly is that a correct impression and then secondly, if so, why should that be? It may of course be that the construction was cheapened off over the years but I do also wonder as has already been stated whether keeping them re-gassed and working at the pressures intended prolongs their life. That was part of my thinking about getting mine re-gassed. BTW having problems changing the rears to the re-gassed ones on SMG. Problem, hopefully solvable, with one and seized pivot shaft the other side not to mention a couple of mounting bolts sheared...
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Re: Dispose of the displacers?

Post by Vulgalour » Wed Nov 05, 2014 12:16 pm

Threelitre, that's quite interesting. I had figured out it was possible to cut the displacer open to access damaged parts but had no idea how to reseal it again afterwards, I now have a little more information to help me resolve the issue with dead displacers. I shall do some further research into what fixtures and fittings are available and if I can find someone with a suitable press to help rebuild the two broken displacers I've kept.

The rust we can deal with, the majority of trim issues can be overcome, but broken displacers continues to be the biggest and most expensive problem facing wedge owners.

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Re: Dispose of the displacers?

Post by beiderbecke » Wed Nov 05, 2014 8:32 pm

As I see it, if the EU Directive re MoT's is enforced, the DfT is forced down this route, and the Hydragas system is altered in any way from the manufacturer's originality, the vehicle could be removed from the road or become ineligible for the test; thus if any alterations are made to the suspension we are knackered for an MoT unless we can come up with a system that incorporates the displacers as I said recently and Vulgalor seems to be working on something similar. At the moment we can alter most things in the interests of safety-related grounds, but that might not last...

Also regarding MoT's, I am of the opinion that there should be a continuation of the test for any year of manufacture - the thought of some pre-war thing covered in guano with a homely mice nest in the boot dragged out of a barn careering towards me while I am stopped at traffic lights while the driver tries to convince his cable-operated brakes to co-operate does not fill me with calmness.

Even if the test is not necessary, I would still get it done every year for my own peace of mind, but it would be up to me to decide if any advises should be seen to. But not everyone will do that, will they...

All in all, we seem to be in a bit of a murky pond, so perhaps we should wait to see if there's light at the end of the MoT saga, but meanwhile see if we can come up with a solution to the problem anyway as I find it disconcerting having to think my wedge might be useless after having lasted this long.

Martin has had his displacers regassed and from the preliminary report seem brilliant in action (rears not withstanding) but you might send yours off and they are not serviceable, i.e., diaphragms ruptured etc., and then what :?: It's not like a hernia operation - opened up and a patch put on (been there, had it done).

Anyway, that's my thoughts - do you have any?

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Re: Dispose of the displacers?

Post by rovamota » Wed Nov 05, 2014 8:58 pm

Well, Martin has had a misfortune with one of his re-gassed displacers, but I will let him explain...
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Re: Dispose of the displacers?

Post by 100 Club » Wed Nov 05, 2014 10:50 pm

In principle, I would only ever have Hydragas on a Wedge.

If going away from Hydragas, I would get a tailgate as part of the deal and own a Renault 20 or 30 :lol:

In terms of alternatives, though, I would have thought it might be possible to re-engineer the rear of a Wedge to accomodate a Peugeot rear axle assembly (from a 405 perhaps?)
Search Google Images for Peugeot rear suspension.

That just leaves the front to deal with........ :shock:

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Re: Dispose of the displacers?

Post by threelitre » Wed Nov 05, 2014 11:53 pm

rovamota wrote:Well, Martin has had a misfortune with one of his re-gassed displacers, but I will let him explain...
Oh, what happened? I am very curious to hear about that now.

Alexander

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Re: Dispose of the displacers?

Post by threelitre » Thu Nov 06, 2014 12:11 am

Up until now it seems that Hydrolastic has been holding up better. But more and more units (at least 40 years old now) will start to age. Explicit failures are mostly the flexible hoses - which can be replaced. The other problem is the ageing rubber spring, which will reduce ride comfort (not as bad as a flat Hydragas unit though) and eventually crack and/or burst. Austin 3 Litre front units seem to be the most vulnerarble to bursting. In this case the solution can only be to open them, replace the rubber and close them again.

I am under the impression - based on my own experience with my two Maxis and a couple of cars in the Netherlands (Maxis, Princesses), that the Hydragas units will in general have a much prolonged service life if kept topped up. Alex Moulton thought the same. This is an easy enough operation. Opening and closing of these units - if done properly on both ends - is a bit more involved than the work in Hydrolastic, but is certainly much easier (and cheaper) to do than developing, adjusting and fitting a completely new suspension to the cars.

The EU directive will not make these modifications illegal if they are currently legal in the UK. The biggest change in road testing the UK will probably see due to that directive is that only indipendent bodies (not doing repairs!) may be able to do the testing in the future. But there are other places, i.e. Germany, where such modifications are legal, but only if the parts are certified for the use on the car - which is doable, but will involve very significant costs. MGF conversion kits are not legal in Germany due to these documents missing! But for the sake of very few wedges outside the UK it is probably not worth considering legal options across Europe.

One thing though: If you consider a wedge (or an Allegro, Maxi, early Metro and so on) as a classic car, I would also consider the suspension to be a significant part of the design. And removing this part will destroy its status as a classic in my opinion - it is like replacing a significant part of a grade II listed building with something modern and different, but of similar function.

I would like to come to the NEC and discuss this, but don't hold your breath, as it is a rather long and expensive trip.

Regards,

Alexander

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Re: Dispose of the displacers?

Post by Gasman » Thu Nov 06, 2014 8:22 am

Yes, changing the rear displacers is not going well. I was going to leave it until after the NEC but as the ride had been so dramatically improved putting the new fronts on I thought I'd give myself a better ride travelling up t'north. So started on the rear nearside. Getting the pivotshaft out a bit of a faff but put the new displacer on and even with only 1 re-gassed rear displacer on the ride was again noticeably improved. So far so good. Unfortunately, next day noticed a pool of green under that rear... Despite being NOS it has a small puncture hole in the body:
IMG_9353_800.jpg
IMG_9353_800.jpg (65.36 KiB) Viewed 18479 times
I've taken it off and put the old one back and thought a little blob of MIG weld would do the trick. I do. however, wonder why the hole is there. Presumably it's rust from the inside but flushing the displacers with fluid before I put them on the car showed absolutely no sign of that.

However, no-one will touch them as they are worried they will explode because they've had hydrolastic fluid in them. So I'm a bit cheesed off at the moment.

The offside pivotshaft I cannot get out despite a bucket load of WD40. Also, despite taking great care I managed to shear not 1 but 2 of the bolts holding the mounting bush to the cross bar. Anyway, I've sorted that albeit I had to take the cross bar out to gain enough access for my clumsy hands to work on it.

So, I've put it all back together with the old displacers until after the NEC...
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Re: Dispose of the displacers?

Post by Dave » Thu Nov 06, 2014 8:33 am

Tough luck Martin, I guess that's 30 year old sheet steel reverting to nature :shock: Although it was NOS, probably not adequately protected :(

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Re: Dispose of the displacers?

Post by Gasman » Thu Nov 06, 2014 9:19 am

A close up (sorry, it's not very good quality) shows a microhole surrounded by a small area with an altered colour.
IMG_9359_CU.jpg
IMG_9359_CU.jpg (38.66 KiB) Viewed 18477 times
Does anyone know whether there really is an explosion risk. Hydrolastic fluid is said to be inflammable and obviously it has alcohol in it but explosive after washing out the inside with soapy water? Seems highly unlikely to me
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Re: Dispose of the displacers?

Post by Dave » Thu Nov 06, 2014 11:46 am

I agree, if sufficiently flushed out with water there will be no fire or explosion risk. Nitrogen is inert so also no fire risk.
I guess the repair would best be "blobs" to avoid heat transfer to the diaphragm. Of course internal inspection could be carried out by borescope and that would give an assessment of damage. If the inside is heavily corroded then it's not worth repairing anyway as it will go again.
I know it's no help in your current situation but I have filled all my spare displacers with fluid and blanked them off, that way at least they will be protected from future corrosion - I hope :roll:

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Re: Dispose of the displacers?

Post by steveb » Thu Nov 06, 2014 5:33 pm

You can get a fuel tank welded so this should not be a problem
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Re: Dispose of the displacers?

Post by threelitre » Thu Nov 06, 2014 9:31 pm

Wow, this is surely a first to see that kind of damage! But I agree that these should be easy enough to weld with a small point. There is no explosion risk - if the welder is in fear he can even fill the unit with inert gas (from his welding bottle) before going at it. Even IF some alcohol would remain inside, when sitting under Argon or similar even this will not be able to combust. Looking at the location of the damage, I would think that there is no diaphragm to damage at that point. I hope you can get this resolved!

Regards,
Alexander

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Re: Dispose of the displacers?

Post by Kevin O’Meley » Thu Jul 19, 2018 11:57 pm

Has anyone looked at the Citron suspension? Similar concept.

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Re: Dispose of the displacers?

Post by rovamota » Sun Jul 22, 2018 9:35 pm

Citroen layout is a completely different concept and would require huge engineering changes.
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Re: Dispose of the displacers?

Post by Vulgalour » Sun Jul 29, 2018 10:05 pm

The big problem with the Citroen system isn't the pump, or the pipes, or even the displacers themselves. It's getting it all mounted to the car in a structurally sound way. Rear end isn't too difficult, but the front end needs serious thought put in. Recently, someone did convert an Allegro to MGF subframes, which was quite a bit of work but not as much as you might expect. I expect subframes of some sort would be the solution with the Princess and something can probably be made up be someone with some knowhow.

Other issues with the Princess is the unconventional horizontally opposed suspension at the front, again this is theoretically possible to replace with any number of compact racing coilover type units, there's a few theories about on that, but the biggest compromise is the ride.

Keeping the soft ride, surprisingly reasonable handling, and compact size is incredibly difficult and while not impossible, definitely cost prohibitive to research and develop.

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Princess Elizabeth
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Re: Dispose of the displacers?

Post by Princess Elizabeth » Thu Aug 16, 2018 6:49 am

Modern cars do not ride better with springs than Hydrogas suspensions.

I applaud the development but it is not necessary as Hydrogas units can and are being refurbished by regassing. Replacing the inner rubbers is undergoing investigation and probably will be possible quite soon.

It is wrong to say that a failed displacer seriously affects the car. True, you go into 'Limp Home' mode.....to use modern speak, but the cars will still drive on their bump rubbers. I have done this.
07742 909986 Princess 2 1.7 HL, Ambassador VDP, Ambassador 1.7 HL (almost broken), VW Passat SE estate 1.9 TD, Renault Kangoo Expression 1.5 DCI, Ford Mondeo TDCi, Citroen C3 SX auto 1.4 petrol (wife)

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Re: Dispose of the displacers?

Post by Vulgalour » Thu Aug 30, 2018 12:42 pm

As have I and the ride is horrendous, I would not recommend it. Driving on failed displacers is so uncomfortable I'd rather get in a BMW and drive that.

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Re: Dispose of the displacers?

Post by rovamota » Thu Aug 30, 2018 9:06 pm

You have to remember, though, that the structure of the car was designed around the use of Hydragas units and the amount of springing absorbed by the Nitrogen is actually quite considerable given its size. Some MGF owners have replaced their Hydragas suspension units with a coilover kit said to improve handling and minimize maintenance. Unfortunately it has transpired that this system has caused major structural problems and owners have reported cracks appearing on the chassis. All that displaced energy has to go somewhere...
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Owner of unique Princess 2000ST 'Special Tuning'.

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Princess Elizabeth
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Re: Dispose of the displacers?

Post by Princess Elizabeth » Fri Aug 31, 2018 7:54 am

Keep the displacers, better than springs.
07742 909986 Princess 2 1.7 HL, Ambassador VDP, Ambassador 1.7 HL (almost broken), VW Passat SE estate 1.9 TD, Renault Kangoo Expression 1.5 DCI, Ford Mondeo TDCi, Citroen C3 SX auto 1.4 petrol (wife)

Vulgalour
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Re: Dispose of the displacers?

Post by Vulgalour » Fri Sep 07, 2018 1:33 am

Part of the issue with the air ride solution was the lack of conventional structural points, the MGF cracked chassis problem really bears that theory out. Fortunately it seems advancements are being made on researching how to properly restore/refurbish the displacers which is realistically the most desirable solution.

The more an alternative solution to the displacers is sought, the more you realise how remarkable a system it really is. Something so mechanically simple is rarely so compact and effective and to date I haven't managed to find a job that does the job as well as the factory option. It really seems that finding a way to remake the displacers is easier and likely more cost effective than an alternative suspension sytem and as the popularity and value of other hydragas sprung cars increases, a solution for the Princess seems more likely.

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Wedge spares

Post by beiderbecke » Sat Sep 08, 2018 1:29 pm

As the wedge parts I put on the 'Wedge Spares Page' recently elicited no response whatever, I will be contacting the local scrap merchant to call next week.

I also have a brand new offside wing which I shall keep but is available.

So if anybody is remotely interested, contact me soon.

Because, REMEMBER - WIGIG...

Vulgalour
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Re: Dispose of the displacers?

Post by Vulgalour » Tue Oct 09, 2018 6:47 pm

I'm remotely interested I just can't collect anything so I didn't ask. I was hoping to be in the new house by now but that's been a right old fiasco, at least then I would have been within collecting distance and could have helped take some items in exchange for lovely pictures of the monarch.

Kevin O’Meley
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Re: Dispose of the displacers?

Post by Kevin O’Meley » Mon Aug 26, 2019 2:20 pm

Can anyone tell me what the weight distribution is on the 4 wheels? Obviously more on the front than the rear.

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Gasman
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Re: Dispose of the displacers?

Post by Gasman » Mon Aug 26, 2019 8:58 pm

It varies dependent on the engine & transmission. Which model are you interested in?
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Oldest known surviving wedge, hand-built 15th Pre-Production Wolseley in June 1974
Last Ambassador down the line in November 1983, Austin Ambassador VDP

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