Xantia Activa Accumulator Sphere

Unread post by **DHallworth** » 09 Feb 2006, 22:35

he hydraulic pump on my activa seems to do a lot of clicking, and i have done the sit on the boot test with the engine turned off and the suspension went down and didn't come back up. After reading another topic am i right in assuming its the accumulator sphere?

Will a standard sphere for a xantia from GSF be suitable for the Activa?
GSF Say its for Certain XM's and all Xantias, but they dont stock much for the activa, so just wondering if it'll fit.

Also, where is the accumulator located on the Activas?
Regards
David.

AndersDK · Unread post by **AndersDK** » 09 Feb 2006, 22:50

Hi David -

All hydraulic Citroens use the same main accumulator sphere type. Its just that on later XM's and Xantia Citroen tried to narrow in the spec on the sphere's initial gas charge - which has NOTHING to do with the function. The way the sphere "wears" out is namely by sloooowly loosing the gas charge over time.
You may happily purchase a BX (or GS) accumulatir sphere and fit it to your Activa. It will work perfect - with absolutely no degradiation in performance, durability or life expectancy.

The sphere is located on the system pressure regulator (PR) - which is also the mounting base for the sphere. The PR in turn is bolted solid to the engine - low front.
Any other spheres found located on chassis members - would be either suspension or active rollbar spheres. Dont touch until new symptoms with your car.

You may start crying now : your Activa is fitted with a total of 10 spheres. Happily they would never need to be replaced all in one go

andmcit · Unread post by **andmcit** » 09 Feb 2006, 23:11

The official Citroën parts database does actually differentiate a separate part number...

5276 06 01 REGULATOR SPHERE - HYDRACTIVE SUSPENSION AND WITH ACTIVE ANTI-ROLL

Bugger, I'll need some spheres for my first Activa purchase in the near future and it now looks though these are different [at least in Citroën' eyes anyhow]

Must be the jetting diameter as I'd expect the size and pressure to be the same.

Andrew

AndersDK · Unread post by **AndersDK** » 09 Feb 2006, 23:35

Andrew - its the MAIN ACCUMULATOR sphere ?
- the one fitted to the pressure regulator.
We are talking the source and reserve of hydraulic pressure here. Not the faintest to do with active rollbars, hydractive, antisink or suspension.
Why would the jet size be different - as there is no jet on this accumulator ?

andmcit · Unread post by **andmcit** » 09 Feb 2006, 23:53

Well spotted Anders!! Yep, I've been looking at a totally different sphere. Not concentrating what with other distractions on ebay!!

That's Ok - at least getting a 'standard' accumulator sphere for my Activa when the time comes wont be as much hassle as I thought a few minutes back!!

All the best,
Andrew

andmcit · Unread post by **andmcit** » 10 Feb 2006, 00:06

Anders, the point you make about the sphere not having a jet is 100% correct. Now I've never meddled with the accumulator one but the hydractive middle spheres which are in effect the same design ARE jetted and can be adjusted which is what I was actually thinking about earlier!!

Their jet is in the main body the sphere is attached to - there's a metal disc in it which can be professionally opened out that will allow a greater volume of fluid into the middle sphere without a detrimental effect of messing up the corner one's that can still do the sport damping. Works REALLY well on an Xm V6 I've seen converted this way - better than any "comfort sphere" conversion.

I agree mind there'd be nothing to gain altering the accumulator sphere the same way mind!!

All the best,
Andrew

Unread post by **DHallworth** » 10 Feb 2006, 00:22

thanks for your help.

Might give it a go at the weekend.
Mine is strange, the pump clicks and the left hand front moves up in stages, click then up, click then up, etc etc.

Seems a bit strange, but i did the test of stop the car and sit in the boot, waited for a minute or two and the suspension didn't move, someone one here mentioned that being a sign of a flat accumulator as it should move up or something with the added weight?

Advice appreciated.
Thanks in anticipation.
Regards
David.

AndersDK · Unread post by **AndersDK** » 10 Feb 2006, 00:31

Right David -

Before you grab out for your dearest leather belonging :
The acc sphere would mostly be in need of replacement - if the regulator keeps clicking - after the car has reached whatever height it can or is set to.
The stepwise raising is just indicative of the system building up pressure - and maybe a li'l bit sticking suspension strut.

The rear suspension not reacting to load change is indicative of a misisng link. A short plastic rod with a cup each end popping on to ball hooks down there under the rear. Item 6 on this schematic.
http://mysite.wanadoo-members.co.uk/cap ... 366010.gif

The link may have popped off, be cracked or is missing. Its a few quid at your local.

Unread post by **DHallworth** » 10 Feb 2006, 00:52

thanks anders,

would that also explain the reason that the rear suspensions sometimes hard?

i.e. bounces rather then being smooth?

Also if i go under the car how easy is it to see where that rod should be?

I am relatively new to the Activa's as you can tell!
Give me my V6 XM anyday!!

David.

Mandrake · Unread post by **Mandrake** » 10 Feb 2006, 01:11

andmcit wrote:Anders, the point you make about the sphere not having a jet is 100% correct. Now I've never meddled with the accumulator one but the hydractive middle spheres which are in effect the same design ARE jetted and can be adjusted which is what I was actually thinking about earlier!!

The rear centre hydractive sphere is exactly like an accumulator, (I have an accumulator on mine which has dropped to approx 50 bars and it works fine)

The front one is a bit different though - it has a much larger centre hole, approximately 8mm compared to the 4mm hole in an accumulator or rear hydractive sphere. Couple that to the 450cc capacity compared to 400cc of an accumulator and there is quite a difference.

Their jet is in the main body the sphere is attached to - there's a metal disc in it which can be professionally opened out that will allow a greater volume of fluid into the middle sphere without a detrimental effect of messing up the corner one's that can still do the sport damping. Works REALLY well on an Xm V6 I've seen converted this way - better than any "comfort sphere" conversion.

Actually there are *two* "jets"

or damper valves... one on either side of the hydractive control block. I recently had them out on mine when I stripped the unit down and they are relatively easy to get out, and are identical to the ones in sphere bases.

After removing the 10mm hydraulic pipes you undo the "plugs" that the pipes were going into with a large socket and the valves just lift out.

I actually wanted to firm up the damping in the soft mode at the rear rather than soften it, and I reduced the centre bypass hole from 1.1mm to 0.9mm. Any change you make to these damping valves only affect the soft mode.

Personally I feel that the default tuning (for the Xantia anyway) is that the soft mode is TOO soft in damping, (mainly at the rear) and the hard mode is too hard...

The big problem with normal "comfort" spheres on the corners is although it makes the hard mode somewhat softer, it also affects the soft mode, which now becomes underdamped unless you tighten up the damping valves in the hydractive unit as well.

I guess it all depends on what you're trying to achieve...

Regards,
Simon

ACTIVE8 · Unread post by **ACTIVE8** » 10 Feb 2006, 11:03

So, how often should a pressure regulator click on an Activa?