Lowering a Xantia suspention

Tony ( snipped-for-privacy@hotmail.com) gurgled happily, sounding much like they were saying :

Easily. Get in the car, reach over for the height lever next to the handbrake, and move it backwards a notch.

But please don't drive it unless it's in the notch marked with a big thick line.

If the height is incorrect, then it can be adjusted by moving the clamp connecting the height corrector to the anti-roll bar. Do this with the car running, set to normal height, and with the weight on it's wheels.

DO NOT DO THIS BY CRAWLING UNDERNEATH THE CAR PARKED ON THE GROUND.

You *WILL* need a lift that supports the car on all four wheels.

Forward on mine :-)

I assume that the OP is asking how to lower the suspension like you can on a normal spring type suspension. This I think is impossible.

You CAN do this by cutting another notch further forward on the panel next to the height adjustment lever, I know many a BX with a forth notch cut. Also means you can notch it back up for speed humps. Be very careful not to set it too low, watch for clearance round driveshafts, BXs foul the anti-roll bar.

-- r

: You CAN do this by cutting another notch further forward on the panel next : to the height adjustment lever, I know many a BX with a forth notch cut.

Is the BX still self levelling at non-standard settings? The DS isn't.

Ian

Malc ( snipped-for-privacy@lightindigooverthere.co.uk) gurgled happily, sounding much like they were saying :

No, it's dead easy. Just adjust the height corrector clamp on the anti-roll bar, so that the height correctors are at their balance point with the bar in a slightly different position.

Yes it is. The self levelling uses the anti-roll bar to sense any change in height and so whatever height setting it is at, it can sense the change and send fluid to that "Axle".

How does the DS do it? I've never worked on one.

-- R

And NEVER NEVER do it on the floor, the car can drop suddenly and there have been several deaths over the years.

I prefer to cut a lower notch for the height control lever, you can then knock it back to standard for speed bumps and the other heights are as standard. I admit we have used the anti-roll bar adjustment on the race car, but we never see any speed bumps.

-- R

R (ruggNOSPAM snipped-for-privacy@yahooNOSPAM.co.uk) gurgled happily, sounding much like they were saying :

In exactly the same way.

: > : You CAN do this by cutting another notch further forward on the panel : > next : > : to the height adjustment lever, I know many a BX with a forth notch cut. : >

: > Is the BX still self levelling at non-standard settings? The DS isn't. : : Yes it is. : The self levelling uses the anti-roll bar to sense any change in height and : so whatever height setting it is at, it can sense the change and send fluid : to that "Axle". : : How does the DS do it? I've never worked on one.

From the anti roll bar, but when you choose a non-standard ride height all you are doing is manually pulling the control rod, so it becomes an open rather than a closed loop control system. It would be much neater if the height control changed the geometry of the control levers so self-levelling still worked - is that how the BX does it?

Ian

PS Never worked on a DS? You lucky sod.

Ian Johnston ( snipped-for-privacy@btinternet.com) gurgled happily, sounding much like they were saying :

The D setup is almost identical to the BX and everything else hydropneumatic (1) in how it works. The control rod, in effect, moves the equilibrium point of the height corrector. Nothing more. The self levelling certainly will still work - except at full high or full low, which put the equilibrium point beyond the extent of the suspension travel. It may well be that high-drive is above that point, too, especially if the car's a bit high in normal-drive.

(1) The only real exception is the s2 CX, where you've got an electric switch controlling a stepper motor - which does exactly the same job as the lever, in moving the front-to-rear control rod. I don't know (or much care) how the C5's Hippo3/3+ does it, especially with the lowering at speed.

You live and learn. Does it make the car corner better? Not that I need better handling, just in a spirit of enquiry.

: Ian Johnston ( snipped-for-privacy@btinternet.com) gurgled happily, sounding much : like they were saying : : : > From the anti roll bar, but when you choose a non-standard ride height : > all you are doing is manually pulling the control rod, so it becomes : > an open rather than a closed loop control system. It would be much : > neater if the height control changed the geometry of the control : > levers so self-levelling still worked - is that how the BX does it? : : The D setup is almost identical to the BX and everything else : hydropneumatic (1) in how it works. The control rod, in effect, moves the : equilibrium point of the height corrector.

No it doesn't, at least not on a DS. The rod from the centre of the antiroll bar is attached to a lever pivoted on the antiroll bar bearing on the left hand side, and the top of that lever drives the height corrector. Car goes down, top of lever moves back, car moves up. And vice versa.

However, when the car is put in one of the two higher ride positions, the top of the lever - and therefore the height corrector actuator - is simply pulled back by around 4 or 8mm. Self levelling therefore only works if the motion of the control rod is more than this, for downwards displacements of the car, and not at all upwards (because the lever is constrained and cannot move forwards at all).

Full up and full down, similarly, just wedge the height corrector all the way in one direction or the other.

How do I know all this? 'Cos I spend several days just a couple of weeks ago replacing the height corrector and antiroll bar - height corrector control linkage, and then resetting it all. I was surprised at how crudely it does the "high ride positions" - it would be far neater if it moved the equilibrium position, but it doesn't.

Ian