suspension still harsh

deian · Post by **deian** » 01 Aug 2006, 19:46

Hi all,

as some of you know well i have harsh suspension problems, last weekend i bled my brakes, and i got no air out of them, i used a long length of clear tubing (maybe about 5 meters worth in the hope of bleeding back into the resevoir). Anyway, from each wheel i filled about a meter worth of lhm into the pipe, and in the end i bled about 1/4litre in all of fluid (into a bottle as the fluid was musky brown in colour)... was this enough? I don't think there is air in the brakes now, no air came out of the brakes anyway.

I still do citrobeotics from time to time and nothing changes, while bleeding the brakes I did grab the droplinks and they seem solid in movement and the rubbers in good shape.

Also I recently replaces my acc.sphere which leaked so that is not the culprit now. I don't think I have more leaking/flat spheres or i would have had air down my brakes right?

So what is it now? Vacuum leak? Which pipes to check? Running out of ideas now people. Would Hydraflush work wonders? Maybe the damper holes are clogged up in the spheres?

Thanks

citronut · Post by **citronut** » 01 Aug 2006, 20:09

you dont allways get air in the brake circuit when susp spheres loose there gas,with the susp on the normal setting bounce on each corner of the car,if you get little or no movement in the susp you have got one or more flat or nearly flat sphere,also the drop links do not afect the ride
regards malcolm

AndersDK · Post by **AndersDK** » 01 Aug 2006, 20:16

The correct suspension height has large influence on the suspension softness.
Check that the driveaxles at front are just exactly horizontal. Adjust the HC clamp on the front arb if necessary
When this is correct - check the door sills are exactly parallel to ground. Adjust the rear HC arb clamp to correct this.

When the height is checked :
Its imperative the car is on level ground - engine is running to provide system pressure - and the height is set to normal. Also each end of the car should be jerked to free any small tension in the suspension.

But first check your tyres are correctly inflated.

The sphere center orifice can never get clogged. There is such large amounts of fluid passing here at hi speed its impossible for any muck to stay.
A flushing with hydracleanse may solve the problem - but I doubt it.

deian · Post by **deian** » 01 Aug 2006, 21:02

well i think my spheres push down ok, but they are citroen marked and the rear ones are dull and rusty abit, so maybe the need changing, although they push down well, the front ones are harder obviously, and there is a little difference between hard and soft, but not much, it certainly doesn't make much of a difference to the handling on corners though (hydractive 2)

what should the height be from the floor to the bottom of the sills?

Mandrake · Post by **Mandrake** » 01 Aug 2006, 21:08

deian wrote:well i think my spheres push down ok, but they are citroen marked and the rear ones are dull and rusty abit, so maybe the need changing, although they push down well, the front ones are harder obviously, and there is a little difference between hard and soft, but not much, it certainly doesn't make much of a difference to the handling on corners though (hydractive 2)

what should the height be from the floor to the bottom of the sills?

There should be a big difference between hard and soft modes for pressing down...

Hard mode at the front you'll hardly be able to push it down by hand (maybe 20mm movement - it feels almost rigid, but its not really, its just the very heavy damping) while soft mode you should be able to push it down to the bump stops from the front bumper.

The rear is much the same - should feel very stiff in the hard mode (about 20mm again) but you should be able to EASILY push it right down to the bump stops in soft mode...

If theres hardly any (but SOME) extra softness in the soft mode you should suspect the Hydractive centre spheres...

Also agree with Anders comments about the ride height - it seems to be particularly fussy on the McPherson strut models like the Xantia. I recently discovered my front ride height was 10mm too low (after all my fiddling over the last few months

) and the ride improved a lot more than I expected changing it by only 10mm.

Unfortunately that means that the ride height is too fussy to set by eyeballing the driveshafts, rear suspension arms, and body sills as some people suggest - you really ought to do it with a measuring tape with the official Citroen figures.

Here's a simple version of that (calculated for a few specific tyre sizes) which I think is originally from the Haynes manual:

The Citroen books contain a more accurate method which involves measuring the height of the centre of the wheel (to account for different tyres/rims) and also gives figures for different models, unfortunately I have no easy way of scanning that in.

The above figures are ok for most models except the Activa and V6. I found that when I calculated it the long way that the bottom column figures matched my 205/60/15 tyres.

As with any height measurement you have to take the average of the car correcting up and down. Press down on the car to make it lift you, then let go so it makes a downwards correction and measure it. Then try lifting it a bit (careful of your back!) so that it starts to get heavy then drop it, then it will make an upwards correction, take the average of the two.

If you just read it in one direction it wont be accurate. If theres more than about 10mm difference between the two readings at the front, the suspension may be under a bit of side thrust so try rolling the car back and forth and measure again.

Regards,
Simon

micitroen · Post by **micitroen** » 01 Aug 2006, 21:20

Looked at all the other replies and I don't think that anyone's mentioned the fact that the LHM should be an almost luminous green colour and not the 'musky brown' that you describe....apologies if teaching suck eggs etc. etc. Might make all the difference and from a reply on a similar subject best to replace it after changing spheres.....they said.

deian · Post by **deian** » 01 Aug 2006, 21:51

i'll take an approximate measurement soon, no i can't push them down too easily in soft mode (doors open), i believe it does ride a little lower to other mk2 xantia's i've seen so this may be it, along with tired spheres and old lhm, but the biggest issue is the height i think, thanks anders and simon, simple things huh!

Post by **Peter.N.** » 01 Aug 2006, 21:55

If the Xantia hydractive is the same as the XM you wont notice any difference between the hard and soft setting when stationary as the 'sport' mode only increases the sensitivity of the system so that the hard mode comes in earlier.

deian · Post by **deian** » 01 Aug 2006, 22:01

i know that, but it should be noticeable between soft and hard upon pushing down on the corners, i know the suspension switch just makes it more sensitive, but i still feel no difference on hard corners, plans will be made to fix it, i will get £200 from work soon for doing a silly nvq2 course, so i will blow that on the 6 new spheres and hydraflush, can't wait!

Mandrake · Post by **Mandrake** » 01 Aug 2006, 22:55

Good point Peter.

When I say soft mode I mean test it with the engine idling, and for hard mode turn off the engine close all doors and wait 30 seconds for a click, and then you're in hard mode. Switching the normal/sport switch will do nothing at all when stationary.

Regards,
Simon

deian · Post by **deian** » 01 Aug 2006, 23:17

is there much of a difference to the 'post' 1996 models mandrake? ur table is up to 1996, and my car is 1998, i guess they sit higher, thats what i've noticed, maybe someone has adjusted my car at some point to those specs there?

steelcityuk · Post by **steelcityuk** » 01 Aug 2006, 23:53

Deian, your cars behaviour sounds very similar to mine.

Up to now I've replaced all spheres except for the rear strut ones. I've bled the brakes and am currently running hydraflush, I've done about 500 miles with it in. My Xantia is soft at the back end but the front is very firm during a push down test. However I think that the front ride height maybe too high. It's next on the list.

I don't have any experience of what a hydractive Xantia should ride like, mine doesn't feel floaty at all. But at the end of the month there's a northern meeting of the CCC near Barnsley so I may go along to that and try to get a ride in another Xantia so I have some kind of reference.

Steve.

citronut · Post by **citronut** » 02 Aug 2006, 08:39

the ride hight adjustment on all hydraulic citroens dose not allter its self,you will probably find your hight corector linkage is partly siezed or may be completly siezed,so you ride hight is not setteling where it should
regards malcolm

Post by **Peter.N.** » 02 Aug 2006, 09:08

OK Simon, I'm with you there - slight misunderstanding. In my experience, all hydropnumatic suspension tends to ride hard over small bumps at low speed, The type and pressure of tyres seems to make more difference than anything else.