Xantia Rear Suspension

Steven · Post by **Steven** » 16 Nov 2003, 21:29

This is the first time I've posted a topic on this Forum. Hi guys.
I have a 2.1 TD Xantia SX with hydropneumatic suspension. Coming home from work one evening I noticed that my headlights were a little higher than usual. When I stopped it was clear that the rear suspension was lower than normal but not on the stops. However, next morning it was fully down and would not come up. Having had a height corrector problem before (with a 1.8 SX) I thought I knew what the problem was - so I bought a new H/C and fitted it.
When I started the engine the front suspension raised and lowered normally but the back stayed fully down and refused to budge. I went through previous threads in this Forum to get some ideas. One was to check that the H/C linkages had been correctly reassembled - yes, all in order. Another was to check that the rubber seals weren't somehow blocking the hydraulic lines - they weren't, as far as I could determine. The third idea was to jack up the back of the car as this sometimes solves the problem - but in my case when I did this the rear went up to max height and has been there ever since. Moving the height control causes the front suspension to move correctly but the back is stuck at max height.
I went under the car (with a pair of axle stands to protect against sudden death) and pushed and pulled the H/C linkages but with no effect. I've now run out of ideas but have a suspicion that the anti sink valve or sphere may have something to do with the problem.
Any ideas before I try to get the car to a Citroen dealer tomorrow ?

Dave Burns · Post by **Dave Burns** » 16 Nov 2003, 23:23

Well the anti sink valve is either open or closed, and if you can jack the rear up and it stayes there then there must be oil getting through, so the valve is opening and the fact that it stayes up there must mean the height corrector has shifted position and is holding it there.
What you describe is typical of a fault with the height control linkage, especialy the plastic ball link, I can't think that it can be anything else but the linkage, very unlikely to be anything to do with the anti sink valve.
I would get back under and have another look, you must be missing something somewhere I think.
Dave

akojic · Post by **akojic** » 17 Nov 2003, 00:39

It seems that that plastic link has been missing or maybe it is broken. At least, it is not too expensive.

Steven · Post by **Steven** » 17 Nov 2003, 14:51

Hi again. I got under the car this morning to take another look at the H/C linkages. Plastic clip definitely OK. Height control bar connected correctly. Springs on H/C linkages look fine i.e. resting against correct parts of assembly.
With engine running I set the height to NORMAL. Got under car (with axle stands + jack in place but not quite touching car) and manipulated the linkages. Pushed H/C arm back and forth such that connection with the hydraulic part of the H/C assembly was fully exercised back and forth. But the rear suspension is still stuck at max height. I then disconnected both the plastic clip and height control lever and did the same again - still no movement of the suspension. I would have thought that, with no mechanical links, manipulating the bar that presumably is directly connected to the H/C valve would release pressure and allow the rear suspension pressure to reduce. What do you think ?
Is it possible that my new H/C (purchased from Citroen main dealer) is duff ? possibly a stuck H/C valve ?

Kowalski · Post by **Kowalski** » 17 Nov 2003, 15:29

If the problem was there with the old H/C valve and you replaced it with a new H/C it is very unlikely that the H/C is the problem, they are relatively simple and reliable. The only things that go wrong with an H/C valve are sticking due to being full of dirt and sticking or the seals getting old and coming apart they don't seem to wear or at least after 150k miles the one on my old Xantia was (and is) like new.
The thing that tended to stick on my Xantia was the linkage controlled from the ride height lever inside the car. If you can, grab a hold of this linkage, give it a good working backwards and forwards and make sure that it is in fact free. They are never completely free since they have a plastic bush that seems designed to give them a bit of "stick" but a little bit of dirt will give them too much "stick" and your suspension get stuck at the wrong height.

Dave Burns · Post by **Dave Burns** » 18 Nov 2003, 03:49

Hmmm...strange, the anti sink valve receives full system pressure as its opening force, difficult to see the valve being able to resist 2500 psi and remain closed, if it is the valve there must be something seriously wrong with it.
Can't be the security valve because the front suspension is working ok.
Have you actualy had the height corrector slide valve move in and out, this wont happen that easily because of the hydraulic damping within it, it will need a constant force held on it to move the slide accross.
Dave

Steven · Post by **Steven** » 19 Nov 2003, 00:13

Thanks for the ideas guys. Dave was the closest to the root of the problem when he suggested taking another look under the car, but thank to all of you. I couldn't afford any more time off work so I got it to the local Citroen main dealer. They said it must be a H/C problem - so they got underneath and after a bit of thought they probably said "we've got a right jerk 'ere". The two hydraulic connections on the H/C that are close together had been connected the wrong way round !! Apparently (in my defence) it's easily done. And with wrong connections as soon as the system was pressurised the new H/C was knackered so yet another H/C was required. As soon as the new H/C was fitted with correct connections, HEY PRESTO, it worked fine. I left the garage somewhat poorer and very embarrassed.
So a word of advice, expensively learnt, for those who dont already do it. When you disconnect the hydraulic lines, label them so that you will definitely put them back in the right place ..... as it says in the Haynes manual. I didn't and got it wrong (although I did think this was a possibility, it looked right !).
One more question ...... how do you regain credibility after a *?&@ up like that ?

JohnW · Post by **JohnW** » 19 Nov 2003, 01:52

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote"><i>Originally posted by Steven</i>

One more question ...... how do you regain credibility after a *?&@ up like that ?
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Thanks for this thread - not one I'll forget. Regaining credibility? Good question. Time is the only answer I can think of. Lots of it!!
Cheers
JohnW

Post by **RichardW** » 19 Nov 2003, 12:50

Funnily enough, my mate did exactly that replacing the rear HC on his Xantia - I thought of it earlier, but dismissed it as we refer to him as 'Accident Jon' - didn't think anybody would repeat it - how wrong!
BTW I think you were done for a new HC, my mate just replumbed and away he went.....
Richard

Kowalski · Post by **Kowalski** » 19 Nov 2003, 14:31

It says in the Haynes book-o-lies that height correctors aren't user servicable but I think they are.
I've had them apart and replaced seals on them, as far as I know there is no way you can break them by connecting them the wrong way around, they are just a 'normal' hydraulic valve.
I think your original HC was most probably OK too, so maybe you've been done twice on the HC front...

Steven · Post by **Steven** » 25 Nov 2003, 01:39

Thanks for the comments guys.
I was charged an hour's labour (55 + VAT in this neck of the woods) and not for the second H/C. And if the original was OK then why did the rear suspension stick at fully down even though the linkages were fully connected and 'free' ?
I think it was a 'simple' H/C problem ...... until I screwed it up.