Dismantle and clean height correctors?

[VertVega]

... Would love a guide posting. Not even sure where the height correcters are to be honest!

This would be a good link to start with, including lots of pics ---> How To - Height Correctors

Also this warning is very important and has to be taken seriously.

As always, prior to starting any work that involves getting underneath a Xantia, or any Citroën with hydraulic suspension, make absolutely certain that the car is firmly supported on axle stands or ramps. This is particularly important when working on the suspension system hydraulics, the car can drop very suddenly with fatal results.

[davetherave]

I bought a load of bits to redo the height correctors from brian primmer at a recent rally included rubber caps and links.
Still have not used them though!

[CitroJim]

unfortunatly seperate parts are no longer available for the height correctors

Hopefully, as the rubber bits are common right across the range, right from (I believe) the earliest DS, if Citroen have declared the rubber bits NFP than I'm sure they'll soon be available again from some enterprising soul as most rubbery bits for the DS are.

Having said that, if the HC is not leaking and it's dismantled/reassembled with due care, the seals can be reused quite happily.

[G4EIY]

Hi Folks,

This link may help with removing and cleaning the damper disks.

http://www.frenchcarforum.co.uk/forum/v ... hp?t=13442

[CitroJim]

Hi Folks,

This link may help with removing and cleaning the damper disks.

http://www.frenchcarforum.co.uk/forum/v ... hp?t=13442

Excellent stuff Brian Thanks!

[steelcityuk]

It's part of my standard routine after buying a hydraulic citroen. Usually it goes like this - engine oil & filter, fuel & air filter, replace spheres, drain lhm tank, wash out and clean filters, refill with hydroflush, drain 1 litre from each brake caliper and keep topping up lhm tank as you go. After somewhere around a thousand miles or so drain tank clean it and filters, depending on state of original lhm maybe refill again with hydroflush. On a part by part basis remove, strip, ultrasonically clean the regulator, height correctors, hydractive blocks. Usually I tweak the regulator whilst I'm at it. Eventually replace hydroflush with lhm after another tank and filter clean.

The amount of gunk that gets trapped in the valve work is surprising, even on cars with very clean lhm. I guess that's why in industry they back flush with hot fluid where possible. I'm still convinced that the sinkers stay supple with less maintenance than the anti sinkers. I also think there is very little movement of fluid after the the height correctors, sure it goes back and forth but how often does it get replaced with 'fresh' fluid unless you gave a excessive leak back problem and even then is it enough to flush gunk back to the filters in the tank?

This HC cme out of the XM SED that I have, the LHM in the tank was bright green -


All just my opinion you understand.

[MeInKiev]

I have an XM with a raising problem in the rear. When the car is cold the rear suspension raises up but tries to keep raising higher than it should. When I turn the engine off, the rear drops dramatically. Then it starts rising a little from the accumulator pressure. Once the system warms up on the road, the rear often drops and then normalises. I changed the rear height corrector for another, with no improvement, which you would think would rule out a dirty height-corrector.
I can't see any slippage on the mechanism at the rear linkage (someone suggested this could be the cause). Any suggestions?

[xantia_v6]

Is your XM HA1 or HA2? (I assume the latter) does it have anti-sink?

It is common for an HA2 system to have strange behaviour at startup if the HA valve has internal leakage.

See viewtopic.php?p=232202#p232202 for the usual fix which involves stretching the spring in the electro-valve.

[thorter]

Unfortunately my memory of the detail is hazy, but I had success cleaning Xantia height correctors on the car without dismantling them. Of course, this may be only part of the problem with the more complex suspension versions.

I disconnected the push on rubber leak off pipe (must be plugged to prevent LHM escaping), and I connected a (temporary) contraption via a length of plastic pipe. This device consisted of an old MIG bottle containing petrol and pressurised from a spare tyre, and two electro valves and a micro switch cam timer. This alternatively pressurised to inject the petrol, then released the petrol back to a bottle. The effect was to push petrol thought the restrictors, thus slightly inflating the height corrector rubber diaphragms, then release it back, thus slowly flushing out the gunge.

I gave it a few hours, and that restored proper suspension operation. For obvious reasons, this should be carried out just before changing the LHM. I have no idea where I got the electro valves, but they were 12 volt, and again the timing was trial and error, but as soon as the diaphragms stop inflating, the pressure can be released to reverse the flow.

Quicker and perhaps easier would be a bidirectional syringe if you can find a suitable one. Clearly the height corrector diaphragms can only stand limited pressure, so a means to limit it would be sensible.