Test driving an SX Xantia

deian · Unread post by **deian** » 26 Dec 2009, 21:07

Then that is a flaw in the genius design of the hydractive suspension isn't it.

One would think they would have done the centre/accum/anti-sink spheres a different size to the strut sphere as putting a sphere with no damping hole could compromise safety. And to have an adapter ring/screw for the pressure tester.

Whats the difference between the accumulator sphere and a centre sphere?

If the accumulator sphere doesn't have a hole, then because the centre sphere is not on a strut then i assume it doesn't have a damping hole? So are the interchangeable?

addo · Unread post by **addo** » 26 Dec 2009, 21:51

Only the "corner" spheres have damped holes. All the others* can be swapped with appropriate adjustments to pressure.

* The rear "anti sink" sphere is of a required type for this location, but a sphere of this type is possible to fit as accumulator, or Hydractive balancing sphere. The threads in its centre hole just become a redundancy.

deian · Unread post by **deian** » 26 Dec 2009, 21:56

so if the accumulator sphere is thought of to be softer than a centre sphere, then to make the soft mode softer on a hydractive car then just pop on an accumulator sphere where the centre sphere is?

addo · Unread post by **addo** » 26 Dec 2009, 22:01

Possibly! There is apparently internal damping in the centre block, and its specs changed several times (were they finetuning it?).

I thought one of the Activa spheres was 75 Bar, and that was the only one higher in pressure than an accumulator (62 Bar).

XantiaDaveEire · Unread post by **XantiaDaveEire** » 27 Dec 2009, 12:18

okey doke

so bx spheres seems to be the way to go

Unread post by **Dommo** » 27 Dec 2009, 17:26

Citroenmad wrote:I hated the new C5 when it first came out, but it has grown on me now and i rather like it too. Id still rather have a C6 though! Some time in the future ...

No, the higher the pressure the better the ride, to an extent anyway, as too much pressure will obviously make it too hard, though 5-10bar over standard is fine. Lower pressure makes them harder, just think over time they lose pressure and the ride becomes harder. So you can add a little pressure to make them softer, or you can experiment by swapping for spheres from different models. If i remember correctly BX spheres on a xantia will make it softer etc. To be honest a car with the correct spheres, new fluid and everything lubricated should give the ride you will need without playing.

If you regass them then no they will never need changing again, so long as the pressure left inside the sphere never gets lower than 15bar. We do our white xms spheres around every 2 years, in nearly 8 years its only needed one set of spheres - as soon as we bought it.

Sounds good the Xantia you have found, though id let him MOT it, as if it fails on something he will have to put it right if you have bought it with 12 months MOT. This might just save you money and hassle.

All Citroen spheres have the chevrons stamped on, if they dont they are not genuine. Many people use the GSF spheres though, and id probably be tempted at that price compared to the Citroens price. We still have a very good stock of genuine Citroen spheres from my dads Citroen business so we hardly ever have to buy them now. As Richard said, ive never known them to lose pressure when not fitted to a car.

We bought a 1994 Xm at the start of this year, it had only done 31K miles and had been stood for 4 years. Its rear spheres were totally shot, no movement at all, however its fronts were very nearly at the right pressure, as it had the 3 dimple spheres fitted from new to the front. Just shows how well those can last.

Ideally you do need the removal tool and yes thats what it looks like. They can be very hard to get off without one, even with a belt strap thing they often wont budge, especially if they have been fitted for some years. Yes it does look a little basic, but it works, there is no other way to do it. Ive seen people using a hammer and chisel to get them off, thats the cowboy way, though its sometimes the only way if they have never been removed before.

Ive no idea where you would get regassed spheres from, and i dont think id buy any either. You dont really know if they have been pressure tested before and had the required pressure remaining, which could give problems. Id much rather get GSF spheres, there will be little difference in price too.

Also you have to remember spheres are all different, xantia rears are different to fronts, then you have your acc. and anti sink. A few people ive spoken too seem confused to this idea and seem to put anything anywhere on the car.

I couldn’t believe one guy at the national this year who thought our Xm had accumulator spheres fitted to the 4 wheels, as he thought it was too soft. Actually it had genuine Citroen spheres which we bought from Citroen for it, they were at the right pressure and with new fluid. Just shows how little some people actually know and shows that their own cars are most likely uncared for heaps. But i couldnt get over my point as he was adamant that he was right. His theory on how a sphere was made was even more amusing!

You also get 'comfort' spheres, they dont usually have more pressure than normal but they do have a larger diameter hole in the sphere. Im not so keen on this idea as doing this seems to play around with the damping in the spheres and lets too much fluid pass though. These often give an uncontrolled ride and too much travel is used, it then gets flummoxed by larger undulations. So in my opinion you cant beat a standard good quality sphere with new LHM in the system and all height correctors etc well lubricated and free'd off, this should make it ride very well.

Where are you located Dom?

Chris.

I'm in Stoke-on-Trent Chris, where abouts in the north east are you? Do you do sphere servicing/regassing/replacement still or not? I'd rather put my money to someone like yourself who seems to know what you're talking about unlike some 'specialists'!

Seems weird at first that slightly more pressure = softer, but when you think about it, it makes sense as the gas is the compressable bit of the suspension system.

So if a car has a firm front end, to the point where it felt like a fairly comfy steel sprung car, would that be knackered front spheres past the point of no return for regassing?

Cheers.

Xaccers · Unread post by **Xaccers** » 27 Dec 2009, 17:38

deian wrote:Then that is a flaw in the genius design of the hydractive suspension isn't it.

One would think they would have done the centre/accum/anti-sink spheres a different size to the strut sphere as putting a sphere with no damping hole could compromise safety. And to have an adapter ring/screw for the pressure tester.

Who in their right mind would put a non-dampened sphere where a dampened one is supposed to go though?
It's like saying the wheel hubs are a design flaw because they don't prevent you fitting 20inch rims which will scrub and prevent you driving.

When you're using millions of spheres on the production line, it makes sense for them all to be made the same, and the required modifications fitted to them, ie make a basic sphere with diaphrams in it, then fit the inner thread for the A/S sphere, dampners for the corner spheres etc, much cheaper.

Citroenmad · Unread post by **Citroenmad** » 27 Dec 2009, 17:41

Im in Hartlepool, so quite a fair way!

No i dont, my dad was a citroen specialist but has since changed jobs. However, we do still have all of the regassing gear and tools and do still do the odd car from time to time. If you think it rides ok and it might regass and you fancy a drive up here, im sure we will be able to do it for you

Eeeeek, well im not as cluded up as some people are about Citroen suspension on here but i have picked up the basics, mainly from my dad who knows everything there is to know about it, as it was his job for over 15 years.

Yes, it does seem a little odd, though obviously way too much pressure and the suspension is going to be getting harder.

Its hard to say without seeing the car but chances are if its still riding ok they might regass, though a pressure test needs to be done to be sure.

Are you planning on going for this xantia then?

Chris

Unread post by **Dommo** » 27 Dec 2009, 18:13

Ah that is quite a trek then, but on veg oil money wouldn't be an issue

If the chap gets it MOT'd we will probably go for it yeah, here's the ebay auction, with pictures now:

http://cgi.ebay.co.uk/S-REG-CITROEN-XAN ... 3ca8aa1b2e

What'd you reckon?

It's just the fairly bumpy ride, slow to lower rear end, and brakes that worry us. The brakes felt as though you were putting your foot on the brake, lifting it off a bit (but still braking), then putting it back down, probably every second or so it would do that.

XantiaDaveEire · Unread post by **XantiaDaveEire** » 27 Dec 2009, 18:15

its like my car

front is raised higher than the rear

Unread post by **Dommo** » 27 Dec 2009, 18:20

How did I miss that...

Is that the anti sink sphere that's at fault? Or if that's knackered should both ends sink?

XantiaDaveEire · Unread post by **XantiaDaveEire** » 27 Dec 2009, 18:23

more often than not when i get back into her the front will drop and the front groans

then the rear will raise up and off we go

Unread post by **Dommo** » 27 Dec 2009, 18:28

XantiaDaveEire wrote:more often than not when i get back into her the front will drop and the front groans then the rear will raise up and off we go

And what have you done to try and sort it?

Xantidote · Unread post by **Xantidote** » 27 Dec 2009, 18:32

The anti-sink sphere only links into the rear suspension - doesn't affect the front ride height

XantiaDaveEire · Unread post by **XantiaDaveEire** » 27 Dec 2009, 18:33

[quote="Xantidote"]The anti-sink sphere only links into the rear suspension - doesn't affect the front ride height[/quote]

would the anti sink sphere make the car any less comfortable at the rear if it needed to be changed ?