VSX Suspension for Novices

[Mandrake]

The memory is affected as well!

The 4 corner spheres were replaced 7 years and 25,000 miles ago, and the accumulator sphere 6 years and 20,000 miles ago, but the a/s and centre spheres don't ever seem to have been replaced. The suspension isn't as soft as I had expected. When the engine is running and the doors are closed, bouncing the corners feels much like a standard car - in hard mode, it's HARD. For the moment, I don't want to spend any more money on it than I can help, but the whole reason for buying a Xantia and particularly a VSX is the soft ride.

7 years ago! Unless they're the multi-layer long life variety (identified by the citroen logo at the top and three dimples spaced around the filler valve at the top) then they will be shot by now, so I'm not surprised it feels hard on a bounce test. A 6 year old accumulator sphere will be shot or nearly so as well.

If you think its going to pass the MOT I would get it through that and then put your feet up for a few weeks as it sounds like you've worked your butt off getting it ready for the MOT... then replace the spheres next month. A full set of IFHS spheres from aepdirect is only about £150, when I got my Xantia V6 last year I just bought the whole set apart from the accumulator sphere which Alex had recently replaced and did all the rest.

By the way as a stop gap measure you can use an accumulator sphere in place of the hydractive regulator/centre spheres if you have any spare ones lying about

A rear hydractive regulator sphere is EXACTLY the same as an accumulator sphere in every way except the pressure is 50 bars instead of 62, so an accumulator sphere that has gone slightly flat is perfect. I put a good (62 bar) accumulator sphere on the rear of my previous Xantia while I was waiting for the correct sphere and the ride was like a Blancmange

The front hydractive regulator sphere is either 70 or 75 bars depending on its size and although they are a slightly bigger sphere with a bigger hole in the neck you could get away with putting an accumulator sphere here for a while as well, certainly if the alternative is to leave a flat or punctured sphere there...

Should a corner bounce (in soft mode) even on the front feel really soft and floaty?

As Jim said, the rear suspension in soft mode should be "lean on it and it bottoms" soft, the front will be stiffer than the rear but still very soft and easy to bounce. With a bit of a push you should still be able to bottom it.

Just recall how soft your previous Xantia was with good spheres and it should be 50% softer again roughly in a bounce test in the soft mode.

[CitroJim]

Centre spheres are often forgotten as they hide well, are misunderstood by the trade and can be little madams to change - they can get very tight and really do need a Pleiades tool.

Rear centres loose pressure over time but fronts, being triple-ply diaphragm ones, tend to be binary - absolutely fine or ruptured - and more often than not absolutely fine.

Note that the correct hydractive front is a 450cc sphere -so bigger than a normal accumulator - and blown up to 70 bars...

[Mandrake]

OEM front Hydractive regulator spheres are indeed 450cc 70 bars, and often the multi-layer diaphragm types but some of the after market ones like GSF and AEP sell are often not multilayer diaphragms (my IFHS one isn't multilayer) and sometimes they're 400cc 75 bars. The larger volume ones are preferable of course.

I wasn't suggesting the accumulator sphere would make for a permanent substitute but at 62 bars its not too far off the 75 bars of a 400cc hydractive sphere, (the ride would be a bit stiffer but still very safe) and would be better than driving the car around with a punctured sphere!

[KennyW]

Old Guy,

Does Miss Garmin use the french policeman from 'Allo 'Allo as the translator.

Kenny

[Old-Guy]

I think he was her French teacher. Mam'selle Garmin on the other hand has a pretty good accent as far as I can tell. I have it on good authority that pronouncing French words like a French person speaking English (a la 'Allo 'Allo), produces more understandable French - even if, like me your grammar is rubbish!

[CitroJim]

I think he was her French teacher. Mam'selle Garmin on the other hand has a pretty good accent as far as I can tell. I have it on good authority that pronouncing French words like a French person speaking English (a la 'Allo 'Allo), produces more understandable French - even if, like me your grammar is rubbish!

Actually, the Gendarme in 'Allo 'Allo would make a brilliant satnav voice... Perfect for a French car I reckon...

I can hear it now...

[Old-Guy]

I mistook the front 'centre' sphere etc. for the accumulator sphere in a rather more accessible place. For no sensible reason, I was expecting it to be behind/below the engine near the height control valve.

No I didn't! That was the Accumulator sphere in the "rather more accessible place"! The 'centre' sphere is exactly where Simon [Mandrake] said.

I had another 'look' at the spheres and suspension behaviour last night, but as I was wearing decent clothes, I didn't grovel in the road to look underneath.

The 4 corner spheres were replaced 7 years and 25,000 miles ago, and the accumulator sphere 6 years and 20,000 miles ago, but the a/s and centre spheres don't ever seem to have been replaced.

BTW, it's an estate, and the front corner spheres are Citroen 3 dimple ones.

As the car had been standing for a couple of days, it was firmly in Hard mode, so I bounced (by dumping my 12st) in the boot corners and on the front wings and slam panel:
The rear bounces much as I would expect from slightly tired spheres - plenty of travel, well damped. The N/S front was rock solid (feels like a flat sphere), the O/S front had an inch of travel at most (almost flat sphere).
Start the engine (doors closed) and wait for the system to pressurise and the suspension to settle. In Soft mode, the rear is not noticeably softer (but the boot was empty with maybe half-a-tank of fuel), but the front bounces like Xantia should with good(ish) spheres, but with rather less roll stiffness.

It seems to me as though the:

• front corner spheres are shot,
  front centre sphere (though probably ancient) is OK and providing all the springing on the front,
  accumulator sphere is OK (none of the usual signs of a tired accumulator)
  rear corner spheres are OK despite being (supposedly) the same age as the front ones
  rear centre sphere is shot (probably ancient, even original as it's too rusty to read anything in situ)
  ant-sink sphere is an unknown quantity until I can find a loose surface where I can safely do an engine-off braking test.

BUT, on limited past experience, I would expect the rear corner spheres (especially on an estate) to go long before the fronts. I'm also surprised that the front centre sphere appears to have lasted so long (possible triple-layer diaphragm not withstanding).

Expert opinions please.

And yet another Hydractive question: Is hard mode triggered by opening the tailgate only, or just by any of the doors?

[Mandrake]

BTW, it's an estate, and the front corner spheres are Citroen 3 dimple ones.

Ah ok, well the 3 dimple ones typically last 10 years or so without significant pressure loss but when they do start to go they often fail completely rather quickly, sometimes from normal pressure to nothing in a few weeks or months. I've not had any fail on me personally though, the long life type are rather good.

As the car had been standing for a couple of days, it was firmly in Hard mode, so I bounced (by dumping my 12st) in the boot corners and on the front wings and slam panel:
The rear bounces much as I would expect from slightly tired spheres - plenty of travel, well damped. The N/S front was rock solid (feels like a flat sphere), the O/S front had an inch of travel at most (almost flat sphere).
Start the engine (doors closed) and wait for the system to pressurise and the suspension to settle. In Soft mode, the rear is not noticeably softer (but the boot was empty with maybe half-a-tank of fuel), but the front bounces like Xantia should with good(ish) spheres, but with rather less roll stiffness.

It seems to me as though the:

• front corner spheres are shot,
  front centre sphere (though probably ancient) is OK and providing all the springing on the front,
  accumulator sphere is OK (none of the usual signs of a tired accumulator)
  rear corner spheres are OK despite being (supposedly) the same age as the front ones
  rear centre sphere is shot (probably ancient, even original as it's too rusty to read anything in situ)
  ant-sink sphere is an unknown quantity until I can find a loose surface where I can safely do an engine-off braking test.

BUT, on limited past experience, I would expect the rear corner spheres (especially on an estate) to go long before the fronts. I'm also surprised that the front centre sphere appears to have lasted so long (possible triple-layer diaphragm not withstanding).

I think your diagnosis is pretty much spot on. In hard mode the rear will be heavily damped but you should still get a decent amount of movement if you push it vigorously. The fact that the rear doesn't get a LOT softer (it should be as soft as butter) in soft mode immediately condemns the rear hydractive regulator (centre) sphere, its almost certainly punctured with no pressure in it. You'll notice a massive improvement in ride when you replace that one... rear corner spheres may be ok although personally on a newly acquired car I'd still replace them anyway...

At the front if it gets a lot softer in soft mode and the front hydractive regulator sphere is one of the multilayer diaphragm types its "probably" ok. It sounds like one of your front strut spheres is punctured if you have no movement at all, however I would comment that even good front strut spheres in hard mode will feel very stiff on a bounce test - you'll get at most an inch or so in the hard mode but the fact that once side has no movement tells us at least one is faulty so I'd certainly replace both so both sides are balanced.

Anti-sink sphere is always an unknown quantity, pressure testing it is the only way to be certain, I'd just replace it.

And yet another Hydractive question: Is hard mode triggered by opening the tailgate only, or just by any of the doors?

Opening the doors triggers soft mode, not hard mode. Citroen calls this the "anti-jolt" system. The purpose is to ensure as much as possible that the connection to the centre spheres is open (soft mode) when the car is being loaded or unloaded to allow pressures to equalize between the three spheres and not allow a higher or lower pressure to be trapped in an isolated centre sphere. Otherwise taking a big load out of the car and then starting the engine would cause a sudden drop in height or vica versa.

Any of the four doors or tailgate should trigger the electrovalves to come on to activate soft mode, if they don't there is a problem with the door light switches or wiring.

Bear in mind that this will put the car electrically into soft mode, but if there is not enough stored pressure still available at the accumulator sphere it will not hydraulically activate soft mode, or perhaps only at one end of the car. Thus if you open doors quite some time after the car has been parked the electrovalves will click and come on but hydraulically the car will still be in hard mode. That's normal, and how long after parking it stops working depends on how well your car holds its accumulator pressure when the engine off and the car is left alone.

It could be anywhere between 30 seconds if the accumulator sphere is dud and/or there is a bad pressure leak in the system, up to about 10 minutes or so if the accumulator sphere is good and the system is free of pressure leaks. Mine seems to manage about 5-10 minutes while my previous Xantia could only manage about 3 minutes at best due to internally leaky electrovalves. Not that it really matters much unless its under a couple of minutes.

[Dommo]

Sounds like the condition I picked my vsx up in. I believe that heat from the engine makes spheres lose pressure, so the front corners take the brunt of it with heat rising off the engine with nowhere to go. The front centre sphere and accumulator get some airflow from behind the radiator so I'd imagine that's why they last longer?

[Old-Guy]

Simon, thanks for another expert dissertation. I'm glad my brain seems to be working again! When I sat on the N/S wing after the car had been left parked for a couple of days without the doors being opened, there was NO detectable change in the gap between wheel-arch and tyre. Doing the same on the O/S, there was a small, but definite, reduction in the gap.

My trouble is that I'm having to completely update my knowledge of 'correct' Xantia suspension behaviour from standard to Hydractive II.

Dommo, My experience with the two SX Estates previously in the family was that the rear corner spheres were the first to go, the front corners lasting longest of all. I'd always put this down to the fact that the front spheres were kept nice and warm/hot by the engine when in use, so the diaphragms are nice and supple and last longer - whereas the rear spheres are out in the cold and wet making the diaphragm material stiffer.

Maybe it's the difference between SX and VSX - the much stiffer sphere damping being the obvious difference though why that should affect diaphragm life I can't imagine....

Anyway, I'm trying not to spend any more on the car than I can avoid until I'm more confident in its reliability. If it were intended as a long-term 'keeper' then I'd change all 8 spheres and get the others tested at some suitable opportunity. However, two new front corner spheres have to be a safety priority - Hard mode equalling rock-solid at the front. Then I'll be able to see how the car feels and I might then fit a new rear centre sphere and, if the car proves reliable, progressively change all the others.

[Mandrake]

Definitely fit a new rear centre sphere, I'm almost certain from your description it will be punctured. You won't get a nice floaty ride with that sphere shot, even the ride in the front seats is affected a lot by the rear suspension.

It's also not good to have the rear suspension stiffer than it should be with the front suspension normal and soft as that can bias the car towards on-the-limit oversteer....

[Ben82]

At one point on the southern outskirts of Niort, she was having so much fun with French road names that she got completely distracted and sent us round in a complete circle.

That's even funnier Guy!

(Male) British TomTom with Swedish road names gets some funny ones, e.g. this was one last year from the route to pick up the C5
http://on.fb.me/19CCrBh" onclick="window.open(this.href);return false;

Had to switch to his Missus to avoid a lot of these whilst driving, since väg means road, so is very common over here. (She just pronounces it vaag)

[Old-Guy]

Thanks Simon. Point taken; ouch, that's £71 from AEP for all 3 . Lots cheaper than GSF who anyway don't seem do all the Hydractive spheres. Just waiting now for AEPs sphere specs.

[demag]

Hi Guy,
When I bought my Xm Vsx some years ago it was VERY stiff, hardly any movement at all. Of course it had been maintained by two Citroen trained mechanics. Yeah! I don't think so.

I replaced most of the spheres as and when I could but it was still stiff, just not quite so much. I repaired the front electrovalve (did the pcb mod on the suspension ecu mainboard.) Slowly but surely it was getting softer but it wasn't like those Youtube videos where the thing seems to fly up and down at the slightest touch. There was a huge thread on the Xm forum about suspension performance and one of the things talked about was running the car on flushing oil. GSF used to sell it, they might still but I don't know. I think it was called Hydroringage or something very similar. I drained the Lhm out of mine as much as possible and refilled with Hydro. It is very thin and cleans all the gunge out of the pipework. Ideally though to do the job properly all the spheres and brake circuits should be bled as well. It recommends running in the car for 500 miles then drain and refill with Lhm but I just left it in mine as I'd heard that a lot of French cars were running on it full time with no ill effects. I drained it after a couple of thousand miles and refilled with more but not before cleaning the tank filters first which were black. So it was definitely working. But its no good using it with flat spheres because if any are punctured they will deposit gunge back into the system.

[Hell Razor5543]

GSF do still sell the Hydroringage, as I bought some off them less than 6 months ago. I cannot remember how much it was, though.