Hi
Please help. My 1994 Xantia locks in height when engine stops and stays level until I restart the engine, then the rear drops down or sometimes the front(one or other). They rise after about 25 seconds. The car has done some towing in the past and the rear end sits very high. Is this a tweak which I can reduce the height to the normal ride level.
Thanks...and a Happy New Year!
John
[:)]
Xantia suspension, drops on starting!
Moderator: RichardW
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Dave Burns
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Losing height fast on start up (especialy the rear) is indicative of the anti sink sphere being well on its way out.
The suspension being too high at the rear is due to problems with the height corrector mechanism, rarely is the actual hydraulic valve at fault.
Wear, partial or total seizure of the pivots and breakage or disconection of the plastic ball link are the main problem areas, these are all fairly easily dealt with.
Towing doesn't affect these cars like those with conventional steel springs so don't be concerned at all about that.
The height of the suspension is easily reset, but before any attempt is made at it the height correctors and all linkages must be intact and free to move.
The car should reliably fall to minimum, rise to normal, then to maximum using the lever in the cabin, don't worry about the intermediate setting if it goes straight past this to maximum, not many well used cars will stop at that height and it has no real use anyway.
So get it on ramps and free it all off with WD40 or the like, then clout it up with heavy grease.
BE WARE OF THE HYDRO CIT, MAKE SURE ITS SAFE TO GO UNDER IT.
Dave
The suspension being too high at the rear is due to problems with the height corrector mechanism, rarely is the actual hydraulic valve at fault.
Wear, partial or total seizure of the pivots and breakage or disconection of the plastic ball link are the main problem areas, these are all fairly easily dealt with.
Towing doesn't affect these cars like those with conventional steel springs so don't be concerned at all about that.
The height of the suspension is easily reset, but before any attempt is made at it the height correctors and all linkages must be intact and free to move.
The car should reliably fall to minimum, rise to normal, then to maximum using the lever in the cabin, don't worry about the intermediate setting if it goes straight past this to maximum, not many well used cars will stop at that height and it has no real use anyway.
So get it on ramps and free it all off with WD40 or the like, then clout it up with heavy grease.
BE WARE OF THE HYDRO CIT, MAKE SURE ITS SAFE TO GO UNDER IT.
Dave
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rory_perrett
- Posts: 715
- Joined: 05 Nov 2001, 19:18
- Location: Leeds, Yorkshire
- My Cars: Xantia Exclusive 110Hdi Estate 1999
- x 1
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Dave Burns
- Posts: 1915
- Joined: 14 May 2001, 05:30
- Location: United Kingdom
- My Cars:
- x 2
Interesting, and from my point of view unlikely, I can's see a reason why that sphere should make any difference to the suspesnion falling in this case, or any other for that matter, maybe I'm missing something but can't think what, anyone care to offer an explanation.
For the suspension to be able to fall in the first place, front or rear, the oil in the strutts MUST have somewhere to go to, and in a big hurry, since its the evacuation of this oil that allows the car to drop, but where does it go?, the only cavity in the system that could accomodate it is in a duff anti sink sphere, Wonder what Anders's take on this subject would be.
Rory, Dave, did you change the sphere's yourselves.
Dave
For the suspension to be able to fall in the first place, front or rear, the oil in the strutts MUST have somewhere to go to, and in a big hurry, since its the evacuation of this oil that allows the car to drop, but where does it go?, the only cavity in the system that could accomodate it is in a duff anti sink sphere, Wonder what Anders's take on this subject would be.
Rory, Dave, did you change the sphere's yourselves.
Dave
Dave -
Clearly I back you up on this - I'm puzzled that a flat accumulator sphere should cause fast REAR sinking on start.
I think the confusion comes in because owners of different system equipped cars thinks all systems works the same - which they DEFINATELY do not.
In this case we have a '94 Xantia which only have the antisink system - not a hydractive 1 or 2 system as found on later models.
For you guys puzzled that this case may not be like on your car - please refer to Gabor's document :
http://www.tramontana.co.hu/citroen/guide.html
Here you have a detailed description of the various systems - still explained in a popular way not letting down the less technical minded.
I recommand the document is read thru a couple of times - as it's so crammed with details - that it takes time to digest it fully.
Start with the basic system - using the BX as an example - then go on to the antisink chapter - then go back a bit and take the Hydractive chapters.
Please note that the ACTIVA system functionally indeed is very special and different from the other systems.
Clearly I back you up on this - I'm puzzled that a flat accumulator sphere should cause fast REAR sinking on start.
I think the confusion comes in because owners of different system equipped cars thinks all systems works the same - which they DEFINATELY do not.
In this case we have a '94 Xantia which only have the antisink system - not a hydractive 1 or 2 system as found on later models.
For you guys puzzled that this case may not be like on your car - please refer to Gabor's document :
http://www.tramontana.co.hu/citroen/guide.html
Here you have a detailed description of the various systems - still explained in a popular way not letting down the less technical minded.
I recommand the document is read thru a couple of times - as it's so crammed with details - that it takes time to digest it fully.
Start with the basic system - using the BX as an example - then go on to the antisink chapter - then go back a bit and take the Hydractive chapters.
Please note that the ACTIVA system functionally indeed is very special and different from the other systems.
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rory_perrett
- Posts: 715
- Joined: 05 Nov 2001, 19:18
- Location: Leeds, Yorkshire
- My Cars: Xantia Exclusive 110Hdi Estate 1999
- x 1
Dave B et al
Yep changed the sphere myself. I think that the rear anti-sink sphere is used to retain pressure in the rear suspension and a valve is shut when the engine is off to prevent pressure leaking away through the rest of the system. When the engine is started this valve opens, if the accumulator sphere is shot it has not able to maintain pressure in the rest of the system while the car has been standing, result any rear anti-sink pressure is lost to the rest of the system causing the back to drop.
Regards
Rory
Yep changed the sphere myself. I think that the rear anti-sink sphere is used to retain pressure in the rear suspension and a valve is shut when the engine is off to prevent pressure leaking away through the rest of the system. When the engine is started this valve opens, if the accumulator sphere is shot it has not able to maintain pressure in the rest of the system while the car has been standing, result any rear anti-sink pressure is lost to the rest of the system causing the back to drop.
Regards
Rory
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rory_perrett
- Posts: 715
- Joined: 05 Nov 2001, 19:18
- Location: Leeds, Yorkshire
- My Cars: Xantia Exclusive 110Hdi Estate 1999
- x 1
Anders
I profess no expertise in the ways of Cit hydraulics, just about came to terms with the 5 spheres on my BX after 6 years before we got a 6 sphere Xantia and now one with 7 or 8 (only found 7 so far). I'm not suggesting that the pressure from the rear reaches the accumulator sphere but disipates into the rest of the system.
Regards
Rory
I profess no expertise in the ways of Cit hydraulics, just about came to terms with the 5 spheres on my BX after 6 years before we got a 6 sphere Xantia and now one with 7 or 8 (only found 7 so far). I'm not suggesting that the pressure from the rear reaches the accumulator sphere but disipates into the rest of the system.
Regards
Rory
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first-things-first
- Posts: 44
- Joined: 13 Oct 2002, 04:20
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Hi All
Just to add my two penneth...
I have a Hydractive 2 XM (I understand somewhat different to the Xantia setup). 8 spheres in total. I have replaced 7 spheres in the last 4 months. The back of the car will drop on starting (after leaving overnight) although it retains height overnight or over a week or more (by retain I mean drops only a couple of inches). Accumulator was changed first and still dropped in same way. Now I have come round to changing other spheres. All have been changed except anti-sink as the mechanics could not get the bugger off as no doubt it has never been changed in last 9 years. Car still sinks on starting as before. This would lead to Anders/Dave explanation that anti-sink is duff, although strange that car will not lose a lot of height even when left over a week (this was case even when only accumulator changed and all rest duff).
Mechanics said that anti-sink would still have some pressure in even after all these years (yeah right!) and would not matter if you can put up with rear suspension dropping on startup. Would this cause any longer term issues with rear brakes/suspension as I understand the anti-sink is rear brake emergency reserve? I now notice that the car is much more floaty and back dips on acceleration (comes back up when steady cruising) - normal behaviour?
Mechanics explanation for dropping was that regulator for rear accumulator/rear centre sphere was sticking and would allow pressure through on startup as not working properly allowing suspension to drop. Rear height regulator senses this and recharges rear suspension to normal height.
I understand the rear anti-sink is a bugger to change (I can imagine as I have seen the crevice it is jammed into). Worth doing for all the hassle? (I can live with the suspension drop each morning start).
Thanks
Andrew
Just to add my two penneth...
I have a Hydractive 2 XM (I understand somewhat different to the Xantia setup). 8 spheres in total. I have replaced 7 spheres in the last 4 months. The back of the car will drop on starting (after leaving overnight) although it retains height overnight or over a week or more (by retain I mean drops only a couple of inches). Accumulator was changed first and still dropped in same way. Now I have come round to changing other spheres. All have been changed except anti-sink as the mechanics could not get the bugger off as no doubt it has never been changed in last 9 years. Car still sinks on starting as before. This would lead to Anders/Dave explanation that anti-sink is duff, although strange that car will not lose a lot of height even when left over a week (this was case even when only accumulator changed and all rest duff).
Mechanics said that anti-sink would still have some pressure in even after all these years (yeah right!) and would not matter if you can put up with rear suspension dropping on startup. Would this cause any longer term issues with rear brakes/suspension as I understand the anti-sink is rear brake emergency reserve? I now notice that the car is much more floaty and back dips on acceleration (comes back up when steady cruising) - normal behaviour?
Mechanics explanation for dropping was that regulator for rear accumulator/rear centre sphere was sticking and would allow pressure through on startup as not working properly allowing suspension to drop. Rear height regulator senses this and recharges rear suspension to normal height.
I understand the rear anti-sink is a bugger to change (I can imagine as I have seen the crevice it is jammed into). Worth doing for all the hassle? (I can live with the suspension drop each morning start).
Thanks
Andrew
Andrew -
Some rear dipping on acceleration is normal - and indicative of good suspension spheres. If the dipping however is severe - even bottoms out the suspension - something is clearly wrong - like wrong type (too soft) spheres.
From my CX era I find this a very comfy behaviour.
The automatic levelling is not supposed to correct the height immediately - a delay of something like 15-30 sec's is build in by a restrictor orifice in the HC. This is to ensure the suspension height does not start oscillating - i.e. gets unstable during drive.
The rear antisink sphere is primaryly used as a rear brakes circuit accumulator - as the brake valve is the most leaking element. Thus the "leak-job" is moved from the suspension spheres to the antisink sphere. The antisink sphere is isolated from the suspension spheres when the car is parked.
The term "rear brake accumulator" should be taken with a grane of salt - as it's known that the brake valve can be a leaky fella. Thus the antisink sphere may not provide for spare rear brakes pressure for longish time. In fact the brake valve may in severe cases be the cause for sudden rear drop on engine start - because it drains the antisink sphere pressure.
During drive the antisink sphere is simply connected in parallel to the suspension spheres - thus behaving like it was part of the supension spheres.
This means the antisink sphere is allways "charged" to the same pressure as in the rear suspension.
Even with a flat rear antisink sphere - you won't experience the car loosing height when parked (it's disconnected !) - only on engine start when the system charges and valves opens - the rear may drop suddenly.
But that's only with a partly flat antisink sphere.
A completely flat antisink sphere would not make the rear drop noticeably - as a totally flat sphere is allready filled with LHM - only taking a few milli-L to be "fully charged".
To fully understand the rearsink feature - please read the document ref above. It's in fact very simple - once you get the idea of the principle.
Some rear dipping on acceleration is normal - and indicative of good suspension spheres. If the dipping however is severe - even bottoms out the suspension - something is clearly wrong - like wrong type (too soft) spheres.
From my CX era I find this a very comfy behaviour.
The automatic levelling is not supposed to correct the height immediately - a delay of something like 15-30 sec's is build in by a restrictor orifice in the HC. This is to ensure the suspension height does not start oscillating - i.e. gets unstable during drive.
The rear antisink sphere is primaryly used as a rear brakes circuit accumulator - as the brake valve is the most leaking element. Thus the "leak-job" is moved from the suspension spheres to the antisink sphere. The antisink sphere is isolated from the suspension spheres when the car is parked.
The term "rear brake accumulator" should be taken with a grane of salt - as it's known that the brake valve can be a leaky fella. Thus the antisink sphere may not provide for spare rear brakes pressure for longish time. In fact the brake valve may in severe cases be the cause for sudden rear drop on engine start - because it drains the antisink sphere pressure.
During drive the antisink sphere is simply connected in parallel to the suspension spheres - thus behaving like it was part of the supension spheres.
This means the antisink sphere is allways "charged" to the same pressure as in the rear suspension.
Even with a flat rear antisink sphere - you won't experience the car loosing height when parked (it's disconnected !) - only on engine start when the system charges and valves opens - the rear may drop suddenly.
But that's only with a partly flat antisink sphere.
A completely flat antisink sphere would not make the rear drop noticeably - as a totally flat sphere is allready filled with LHM - only taking a few milli-L to be "fully charged".
To fully understand the rearsink feature - please read the document ref above. It's in fact very simple - once you get the idea of the principle.
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first-things-first
- Posts: 44
- Joined: 13 Oct 2002, 04:20
- Location:
- My Cars:
Hi Anders
Thanks again for the insight.
I hoped this suspension behaviour was normal as my father has had many (4+) CX Familale (right spelling?) 7 seaters. Only got out of the habit as my mother could not take those "damned citroens" always being repaired. He was using as taxi's and maintenance is all part of the normal running of a car. Having a full set of people on board and their luggage would have killed most cars suspensions but Citroens are always flat and level.
He says this is the behaviour he used to get - although he loved the way the back end would dip first on CX estates as the rear brakes came on before the fronts.
My one only dips a bit and never bottoms. Strange to have a smooth riding car with the Citroen feel now. Used to be flat and level under all braking/acceleration and quite harsh over any sort of marks or holes in the road. Tried all sorts of tyre pressures to see if they would help. I can also now hear the whirrs of the (I assume) electrovalves in the rear accumulator which did not happen before (as I assume the sphere was flat and no doubt original).
Braking is much more progressive as well.
Thanks
Andrew
Thanks again for the insight.
I hoped this suspension behaviour was normal as my father has had many (4+) CX Familale (right spelling?) 7 seaters. Only got out of the habit as my mother could not take those "damned citroens" always being repaired. He was using as taxi's and maintenance is all part of the normal running of a car. Having a full set of people on board and their luggage would have killed most cars suspensions but Citroens are always flat and level.
He says this is the behaviour he used to get - although he loved the way the back end would dip first on CX estates as the rear brakes came on before the fronts.
My one only dips a bit and never bottoms. Strange to have a smooth riding car with the Citroen feel now. Used to be flat and level under all braking/acceleration and quite harsh over any sort of marks or holes in the road. Tried all sorts of tyre pressures to see if they would help. I can also now hear the whirrs of the (I assume) electrovalves in the rear accumulator which did not happen before (as I assume the sphere was flat and no doubt original).
Braking is much more progressive as well.
Thanks
Andrew
I have the following theory about sinking of front or rear end, caused by flat accumulator sphere.
Suppose you come home with loaded car (you and your better half on the front seats, some children at rear seats, and some luggage in the boot). You park the car in front of your home, switch off the engine, then everybody get out.
What will happen: if accu sphere is flat, pressure in it will drop to zero several second after switching the engine off, and anti-sink valves will close. After unloading the car, it will rise, so height correctors will open the return lane from suspension cylinders to LHM tank. But the car will not sink back to the normal height, because A/S valves are already closed.
Next time you enter the car. Suppose you are alone this time, so the car won't dive back to normal height, especially rear, and height correctors may remain open (they need several second to react anyway). After switching the engine on, anti-sink valves will open and the car will drop, then after a few seconds it will be back to the normal height.
So - I think this is possible.
Suppose you come home with loaded car (you and your better half on the front seats, some children at rear seats, and some luggage in the boot). You park the car in front of your home, switch off the engine, then everybody get out.
What will happen: if accu sphere is flat, pressure in it will drop to zero several second after switching the engine off, and anti-sink valves will close. After unloading the car, it will rise, so height correctors will open the return lane from suspension cylinders to LHM tank. But the car will not sink back to the normal height, because A/S valves are already closed.
Next time you enter the car. Suppose you are alone this time, so the car won't dive back to normal height, especially rear, and height correctors may remain open (they need several second to react anyway). After switching the engine on, anti-sink valves will open and the car will drop, then after a few seconds it will be back to the normal height.
So - I think this is possible.
Nipping back up the thread a bit - I missed a lot of chat last night!
I did change the acc sphere myself, and the two front suspension spheres at the same time. I've only had the Xantia a couple of months and it's my first hydraulic Cit so I have no technical input to make!
When I brought the car I knew that the two front suspension spheres were poor as there was very little give in the suspension at rest. Over the first month the ride deteriorated and became very choppy if I drove over a speed ramp at an angle. This all cleared up after changing the spheres.
I used to have 15-17 second clicking and stop/start brakes and after reading up on the acc sphere here I decided I'd change that at the same time. The sphere had the original type of code stamped on it so I guessed it had never been changed. Having changed the acc sphere the brakes are far more controllable and the ticking has slowed loads. I find the suspension height changes are a lot prompter now - I used to have to wait 30 secs on low before she'd start to rise, now I can go down and straight back up (even though the process isn't quick). Now I only see the stop lamp at start-up, not even during Citrobics.
I’m going to ignore the action of the front on start-up as I have found that it still sometimes winds itself up if I’m doing a lot of steering when I stop and has the tendency to stick high and drop suddenly.
Before the sphere changes the back used to drop about 4" on starting the engine and then pump itself up within 5-10 secs. If parked for less than ½ an hour it would never drop. I had put this down to the anti-sink sphere getting old but I decided it could wait.
Since changing the front and acc spheres the back doesn’t drop on start-up – I’ve left the car parked for two days (the longest interval) and it was fine then too. The back always seems to be the same height as when I left it so maybe the anti-sink is working.
I did change the acc sphere myself, and the two front suspension spheres at the same time. I've only had the Xantia a couple of months and it's my first hydraulic Cit so I have no technical input to make!
When I brought the car I knew that the two front suspension spheres were poor as there was very little give in the suspension at rest. Over the first month the ride deteriorated and became very choppy if I drove over a speed ramp at an angle. This all cleared up after changing the spheres.
I used to have 15-17 second clicking and stop/start brakes and after reading up on the acc sphere here I decided I'd change that at the same time. The sphere had the original type of code stamped on it so I guessed it had never been changed. Having changed the acc sphere the brakes are far more controllable and the ticking has slowed loads. I find the suspension height changes are a lot prompter now - I used to have to wait 30 secs on low before she'd start to rise, now I can go down and straight back up (even though the process isn't quick). Now I only see the stop lamp at start-up, not even during Citrobics.
I’m going to ignore the action of the front on start-up as I have found that it still sometimes winds itself up if I’m doing a lot of steering when I stop and has the tendency to stick high and drop suddenly.
Before the sphere changes the back used to drop about 4" on starting the engine and then pump itself up within 5-10 secs. If parked for less than ½ an hour it would never drop. I had put this down to the anti-sink sphere getting old but I decided it could wait.
Since changing the front and acc spheres the back doesn’t drop on start-up – I’ve left the car parked for two days (the longest interval) and it was fine then too. The back always seems to be the same height as when I left it so maybe the anti-sink is working.