Xantia Activa suspension overhaul

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Hadmund
(Donor 2025)
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Xantia Activa suspension overhaul

Unread post by Hadmund »

After 5 months of owning a xantia Activa and 8 days of it actually being drivable I've decided that something actually has to happen.

My plan is overhaul the suspension in a way where i can get it as close to "how it's supposed to be". This is the first hydropneumatic car I've gotten the "pleasure" to work on and I don't really know how it's supposed to feel since it was in quite a state when i bought it.
To sum it up, I didn't realize that the strut tops had nearly turned to dust and I only realised this after 8 days of driving when an electrical fault in the indicator switch almost lit my airbag on fire... The LHM gauge says it's overful, honestly looks like the previous owner just brimmed it. Other things that come to mind are the outside door trim piece falling off, speedometer not working half the time and some wires going to the front brakes that look mysteriously like someone has attacked them with a wire cutter :| . I pretty much just want to overhaul the entire suspension system as I don't have the service history and I don't trust the previous owner any further than i can spit.

If anyone has any resources on such a procedure they would be greatly appreciated. Another thing I'm looking for are possible quality of life modifications. I've seen people talk about switching spheres to the modern type and adding pressure gauges to the spheres somehow.

So far I've started getting the strut tops off of the car so they can be refurbished. In line with the car this has of course not gone as planned and they seem to be stuck onto the struts even after removing all the bolts that I'm aware need removing. My mad 1am dash to try and get them off before leaving on holiday ended with me hammering at the top bolt that passes through the strut top trying desperately to get it off. This ofcourse didn't work and I'm not sure if it their are more steps or if it's just decided to weld itself to the strut.
Rant over.

Pretty much I just need some tips on what parts likely need changing and what procedures/modifications need to be done to accomplish this. I'm currently on holiday, but I'll be back in 5 days and can post pictures and check things if necessary.

-Odin
Michel

Re: Xantia Activa suspension overhaul

Unread post by Michel »

Hadmund wrote: 02 Aug 2023, 15:52 After 5 months of owning a xantia Activa and 8 days of it actually being drivable I've decided that something actually has to happen.
-Odin
Having owned a couple myself, I think you did well to get 8 days of it being driveable :rofl2:

Start here :

viewforum.php?f=17

there's loads on there. CitroJim is the expert on such things, though plenty of others know a great deal.

I found sertraline helped me recover from Activa ownership :-p
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CitroJim
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Re: Xantia Activa suspension overhaul

Unread post by CitroJim »

Hi Odin and welcome to Activa ownership :D I loved mine and loved all three I had over the years...

That I no longer have one is a lifestyle choice now I'm old, never drive far and have no need of such a big car.

To remove the strut pistons from the strut tops I've never failed by loosening the big central nut so that it lies flush with the top of the thread and then giving it a firm and deliberate dead-blow from a big hammer. I use a 2Kg Club Hammer. No fairy blows, good firm heavy, meaningful ones carefully but firmly delivered ;)

It's essential you place the nut in the precise position on the piston thread to prevent damage to the thread. If not, the risk is that the thread will deform and you'll not get the nut back on again...

Don't hesitate to ask more Activa questions as and when you need answers ;)
Jim

A bit of a Citroen AX fan...
Hell Razor5543
(Donor 2023)
Posts: 14263
Joined: 01 Apr 2012, 09:47
x 3275

Re: Xantia Activa suspension overhaul

Unread post by Hell Razor5543 »

CitroJim wrote: 02 Aug 2023, 17:49 Don't hesitate to ask more Activa questions as and when you need answers ;)
14 reams of paper later...
James
ex BX 1.9
ex Xantia 2.0HDi SX
ex Xantia 2.0HDi LX
ex C5 2.0HDi VTR
ex C5 2.0HDi VTR
ex C5 2.2HDi VTX+

Yes, I am paranoid, but am I paranoid ENOUGH?
Out amongst the stars, looking for a world of my own!
RichardW
Forum Treasurer
Posts: 12441
Joined: 07 Aug 2002, 17:12
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Re: Xantia Activa suspension overhaul

Unread post by RichardW »

Hell Razor5543 wrote: 02 Aug 2023, 19:13
CitroJim wrote: 02 Aug 2023, 17:49 Don't hesitate to ask more Activa questions as and when you need answers ;)
14 reams of paper later...
...It will still be looking at you lopsided, and the rear ram will still be leaking 🤣
Richard W
Armidillo
(Donor 2022)
Posts: 477
Joined: 28 Apr 2020, 02:18
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Re: Xantia Activa suspension overhaul

Unread post by Armidillo »

Hadmund wrote: 02 Aug 2023, 15:52 After 5 months of owning a xantia Activa and 8 days of it actually being drivable I've decided that something actually has to happen.

My plan is overhaul the suspension in a way where i can get it as close to "how it's supposed to be". This is the first hydropneumatic car I've gotten the "pleasure" to work on and I don't really know how it's supposed to feel since it was in quite a state when i bought it.
To sum it up, I didn't realize that the strut tops had nearly turned to dust and I only realised this after 8 days of driving when an electrical fault in the indicator switch almost lit my airbag on fire... The LHM gauge says it's overful, honestly looks like the previous owner just brimmed it. Other things that come to mind are the outside door trim piece falling off, speedometer not working half the time and some wires going to the front brakes that look mysteriously like someone has attacked them with a wire cutter :| . I pretty much just want to overhaul the entire suspension system as I don't have the service history and I don't trust the previous owner any further than i can spit.

If anyone has any resources on such a procedure they would be greatly appreciated. Another thing I'm looking for are possible quality of life modifications. I've seen people talk about switching spheres to the modern type and adding pressure gauges to the spheres somehow.

So far I've started getting the strut tops off of the car so they can be refurbished. In line with the car this has of course not gone as planned and they seem to be stuck onto the struts even after removing all the bolts that I'm aware need removing. My mad 1am dash to try and get them off before leaving on holiday ended with me hammering at the top bolt that passes through the strut top trying desperately to get it off. This of course didn't work and I'm not sure if it their are more steps or if it's just decided to weld itself to the strut.
Rant over.

Pretty much I just need some tips on what parts likely need changing and what procedures/modifications need to be done to accomplish this. I'm currently on holiday, but I'll be back in 5 days and can post pictures and check things if necessary.

-Odin
Hi Odin

We salute your courage - you were supposed to start with an SX (only 6 spheres) and work your way up :-D .

As a Xantia owner I can venture a couple of answers:

1) LHM tank level. Did you check the gauge with the suspension set to high? Leave the engine running and wait until the car has stopped rising and the suspension is rock hard. Even if it's overfull, it's no big deal - as long as it doesn't overflow when you set the suspension to low it really won't matter.

If as you say you don't know the service history, I would recommend changing the fluid. It is not too difficult to remove the LHM tank (set suspension to low first), clean it out thoroughly, and refill with fresh LHM. To complete the job, bleed the brakes until fresh fluid flows out the bleed nipples. The down side of doing this on a 20+ year old car is that you inevitably disturb rubber LHM hoses. If they are old and brittle they may crack when disturbed...

2) The wires to the front brakes will (hopefully) be the brake pad wear indicators (not the ABS sensors :shock: ). Sadly I've found it common for people to cut off the brake wear indicators - as long as you monitor the pads yourself, it does mean you can get more life out of the pads without an annoying warning light.

3) The "modern type" spheres would be dual membrane. These do have much longer life than the usual single membrane ones. AFAIK, dual membrane spheres were made for C5s, not Xantias, but it's usually possible to find a match for at least some of the 10 spheres that an Activa has. Suspension spheres have 2 different parameters that matter - pressure and valve diameter, while accumulator spheres have a pressure rating, but have no valve. Can I caution you not to experiment with suspension spheres that do not meet the standard specifications for both pressure and valve diameter - apart from being potentially dangerous, you will likely be left with a less than optimum balance between ride and handling. Accumulator spheres probably allow a little more leeway, but low pressures are to be avoided (on all spheres).

Remember that hydraulic suspension (when working properly) seems the reverse of steel springs - when you add load to a steel sprung car, the added mass overcomes the resistance of springs and dampers, and the ride seems to get softer/more bouncy. With hydraulics, the more load you add, the stiffer the system gets.

If the hydractive system (which uses electronics to switch extra spheres in and out of the suspension system) is not working, the ride will be very stiff all the time, even with all spheres at the correct pressures. The simplest test for a functioning hydractive system is to park the car in a quiet place (inside a garage is ideal), turn the engine off, then open a front door and listen for a high pitched whine coming from under the car. If you can hear the whine, the suspension should be soft (much more so at the rear than at the front). When the whine stops (30 seconds(?) after closing all doors) the suspension should be much stiffer.

If you can hear the whine but the suspension remains stiff then you almost certainly have some flat spheres.

Please keep posting - we'll be following your journey with great interest!

Cheers
Alec
Hadmund
(Donor 2025)
Posts: 29
Joined: 03 Apr 2023, 08:07
x 3

Re: Xantia Activa suspension overhaul

Unread post by Hadmund »


Hi Odin

We salute your courage - you were supposed to start with an SX (only 6 spheres) and work your way up :-D .

As a Xantia owner I can venture a couple of answers:

1) LHM tank level. Did you check the gauge with the suspension set to high? Leave the engine running and wait until the car has stopped rising and the suspension is rock hard. Even if it's overfull, it's no big deal - as long as it doesn't overflow when you set the suspension to low it really won't matter.

If as you say you don't know the service history, I would recommend changing the fluid. It is not too difficult to remove the LHM tank (set suspension to low first), clean it out thoroughly, and refill with fresh LHM. To complete the job, bleed the brakes until fresh fluid flows out the bleed nipples. The down side of doing this on a 20+ year old car is that you inevitably disturb rubber LHM hoses. If they are old and brittle they may crack when disturbed...

2) The wires to the front brakes will (hopefully) be the brake pad wear indicators (not the ABS sensors :shock: ). Sadly I've found it common for people to cut off the brake wear indicators - as long as you monitor the pads yourself, it does mean you can get more life out of the pads without an annoying warning light.

3) The "modern type" spheres would be dual membrane. These do have much longer life than the usual single membrane ones. AFAIK, dual membrane spheres were made for C5s, not Xantias, but it's usually possible to find a match for at least some of the 10 spheres that an Activa has. Suspension spheres have 2 different parameters that matter - pressure and valve diameter, while accumulator spheres have a pressure rating, but have no valve. Can I caution you not to experiment with suspension spheres that do not meet the standard specifications for both pressure and valve diameter - apart from being potentially dangerous, you will likely be left with a less than optimum balance between ride and handling. Accumulator spheres probably allow a little more leeway, but low pressures are to be avoided (on all spheres).

Remember that hydraulic suspension (when working properly) seems the reverse of steel springs - when you add load to a steel sprung car, the added mass overcomes the resistance of springs and dampers, and the ride seems to get softer/more bouncy. With hydraulics, the more load you add, the stiffer the system gets.

If the hydractive system (which uses electronics to switch extra spheres in and out of the suspension system) is not working, the ride will be very stiff all the time, even with all spheres at the correct pressures. The simplest test for a functioning hydractive system is to park the car in a quiet place (inside a garage is ideal), turn the engine off, then open a front door and listen for a high pitched whine coming from under the car. If you can hear the whine, the suspension should be soft (much more so at the rear than at the front). When the whine stops (30 seconds(?) after closing all doors) the suspension should be much stiffer.

If you can hear the whine but the suspension remains stiff then you almost certainly have some flat spheres.

Please keep posting - we'll be following your journey with great interest!

Cheers
Alec
I'm guessing it's too late to get an SX, I can't just turn off the extea spheres during my first year of ownership? :wink:

1) I've checked the level while it was on high and it was still overful. I've spilled quite a bit in the driveway so far.
How much LHM do I need to fill the whole system? I've got a litre lying about somewhere but I'm assuming I need more than that.
If I need to change the hoses can I just get a length of tubing and cut and bend whatever I need or do I need to buy individual stretches?

2) I'm pretty sure it's the brake wear sensor, I've had the warning light turn on while driving even though all of brakes are in good shape.

3) I'll look into sourcing the newer type spheres where I can get matching ones and keep to the original ones where necessary. I'll have a listen for the whining when I've got new strut tops on and the car is carrying it's own weight.

Thank you very much for the suggestions, I'll try to make at least a short post whenever I've made some sort of progress.

- Odin
Hell Razor5543
(Donor 2023)
Posts: 14263
Joined: 01 Apr 2012, 09:47
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Re: Xantia Activa suspension overhaul

Unread post by Hell Razor5543 »

@Hadmund. A trick I learned (from a Citroen mechanic who ran green blooded Citroens) is to loosen off all of the spheres (by one turn) every six months or so, and then do them back up hand tight. If they are left alone for a long time the spheres can get biblically tight (especially the Activa ones), to the point where extreme measures are required to remove them (when I say hammer and chisel I am NOT joking; I have had to do this myself).
James
ex BX 1.9
ex Xantia 2.0HDi SX
ex Xantia 2.0HDi LX
ex C5 2.0HDi VTR
ex C5 2.0HDi VTR
ex C5 2.2HDi VTX+

Yes, I am paranoid, but am I paranoid ENOUGH?
Out amongst the stars, looking for a world of my own!
Hadmund
(Donor 2025)
Posts: 29
Joined: 03 Apr 2023, 08:07
x 3

Re: Xantia Activa suspension overhaul

Unread post by Hadmund »

Hell Razor5543 wrote: 04 Aug 2023, 08:51 @Hadmund. A trick I learned (from a Citroen mechanic who ran green blooded Citroens) is to loosen off all of the spheres (by one turn) every six months or so, and then do them back up hand tight. If they are left alone for a long time the spheres can get biblically tight (especially the Activa ones), to the point where extreme measures are required to remove them (when I say hammer and chisel I am NOT joking; I have had to do this myself).
I don't doubt you for a second. I probably applied closer to 300nm when removing the drivers side front strut sphere. Broke the chain on my chain wrench 4 times and had to change to a extra strong chain for a tandem bike.
Hell Razor5543
(Donor 2023)
Posts: 14263
Joined: 01 Apr 2012, 09:47
x 3275

Re: Xantia Activa suspension overhaul

Unread post by Hell Razor5543 »

Hadmund wrote: 04 Aug 2023, 16:27
Hell Razor5543 wrote: 04 Aug 2023, 08:51 @Hadmund. A trick I learned (from a Citroen mechanic who ran green blooded Citroens) is to loosen off all of the spheres (by one turn) every six months or so, and then do them back up hand tight. If they are left alone for a long time the spheres can get biblically tight (especially the Activa ones), to the point where extreme measures are required to remove them (when I say hammer and chisel I am NOT joking; I have had to do this myself).
I don't doubt you for a second. I probably applied closer to 300nm when removing the drivers side front strut sphere. Broke the chain on my chain wrench 4 times and had to change to a extra strong chain for a tandem bike.
Ouch!

You need to initially loosen off the rear strut spheres with the suspension at height (but with support, to protect against the suspension suddenly dropping and crushing you). This is because the rear struts, when the suspension is at its lowest, can easily move (so the struts will rotate in their fixings, rather than the spheres unscrewing from the strut). If you do have to use the hammer and chisel (only do this on strut spheres) tap the chisel directly into the weld to provide a 'divot' (to act as a purchase point). Once you have a large enough 'divot' angle the chisel so as to unscrew the sphere, and start taping again.

I would not use the hammer and chisel technique on other spheres, as the supporting brackets may not be up to the strain.
James
ex BX 1.9
ex Xantia 2.0HDi SX
ex Xantia 2.0HDi LX
ex C5 2.0HDi VTR
ex C5 2.0HDi VTR
ex C5 2.2HDi VTX+

Yes, I am paranoid, but am I paranoid ENOUGH?
Out amongst the stars, looking for a world of my own!
Wesa
Posts: 5
Joined: 25 Feb 2016, 12:59
x 2

Re: Xantia Activa suspension overhaul

Unread post by Wesa »

About fluid level, the indicator has a bad habit to stuck on highest position. Small knoks to transparent sight glass when suspension is highest position should help
-79 GS X3 EV project
-84 CX Prestige 2.5
-88 CX 2,0 TRE
-96 Xantia Activa 2.0 tct
-08 C5 (X7) hdi 170
Michel

Re: Xantia Activa suspension overhaul

Unread post by Michel »

Firstly, make sure your car is supported on stands. On your shared drive between your neighbour's cars should be ok.
IMG00879-20100828-0957.jpg
Next, ensure you have a bowl to catch any tiny LHM drips in. Your significant other's favourite bowl, perhaps? Place it in the wrong place initially, to make you really unpopular with the neighbours, unless yours like LHM on the shared drive, of course. Spray penetrating fluid liberally all over every thing you may have to undo. Ensure to get a bit in your eyes, for full effect.
IMG00871-20100827-1849.jpg
Lie on your back. Ensure your mouth is open to catch bits of falling rusty crap. You'll see something like this..
Be quite violent with the sphere tool, but careful at the same time as this particular sphere is mounted on a bracket which can bend. Pause every minute or so to have a good swearing session, as it is hard to put enough effort into undoing the sphere AND swear at the same time.
IMG00875-20100827-1926.jpg
The next step is to move the bowl again, to ensure that the jet of escaping LHM goes all over your head and face, rather than in the bowl.
IMG00874-20100827-1851.jpg
Once this sphere (and seal) has been changed, you can move on to the rest. I seem to recall this particular sphere (front Activa sphere?) being "fun" to do also.
IMG00881-20100828-1556.jpg
You will then be left with some green balls, and a bowl with some extremely dodgy looking fluid in it...
IMG00880-20100828-1139.jpg
Repeat the procedure for the other 6 spheres, whilst wondering why the f#$k you bought an Activa in the first place.

I hope this guide helps :-P
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CitroJim
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Re: Xantia Activa suspension overhaul

Unread post by CitroJim »

Whilst Activa ownership can be a bit traumatic, it does not need to be. I offer these articles that may be of assistance...

All you need to know about spheres and related topics:

viewtopic.php?t=24595

An Activa buyer's guide that contains much useful infiormation to determine if all is good:

viewtopic.php?p=188515

And, how the suspension works:

viewtopic.php?t=58006

Hope that helps a bit :)
Jim

A bit of a Citroen AX fan...