Xantia rigidity regulator

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Duracell
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Xantia rigidity regulator

Post by Duracell »

Hi

I've developed a leak from the front rigidity regulator on my 1999 Xantia 110 Hdi exclusive. It does not appear to be coming from the sphere seal or running down pipework from other areas and also does not leak when stationary - only when its driven - so its difficult to see where its coming from as the whole regulator and underside of the car has LHM on it when I get to look at it. My instinct is to take it off and replace all the seals, but unfortunately Citroen don't seem to list them so I don't know if they are available. Before I strip this down and block up my drive with a car that can't easily be moved, does anybody know of a common problem on these regulators and also if the common 14mm and 19mm seals used elsewhere and available are likely to fit?

Thanks

Richard
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Re: Xantia rigidity regulator

Post by citronut »

whats the rigidity regulator Richard,

is it some kind off V*i*a*g*r*a drip feed system fitted in the suspension system of your car :o :twisted: :rofl2: :-D :wink:*
Regards, malcolm.

current ride a BX 1.7 TZD estate
1986 MK1 BX 1.9na D Auto(in Mothman Andy's stable )
layed up roppy 1.9TD XANT estate, now gone to meet her maker
purple and lilac metalic 2CV(VIOLET)registered to her in doors
1972 DS special been layed up aprox 31 years
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Re: Xantia rigidity regulator

Post by Duracell »

Very good Malcolm - I see you're on form today - Just in case there was any seriousness involved in your reply its what Citroen call the hydroactive center sphere.

Regards

Richard
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Re: Xantia rigidity regulator

Post by citronut »

Duracell wrote: Just in case there was any seriousness involved in your reply its what Citroen call the hydroactive center sphere.

Regards

Richard
:rofl2: :rofl2:

ok
so theres not much it can leak from on this unit is there????

looking at service citroen it just a sphere with the pipe going straight into that
Regards, malcolm.

current ride a BX 1.7 TZD estate
1986 MK1 BX 1.9na D Auto(in Mothman Andy's stable )
layed up roppy 1.9TD XANT estate, now gone to meet her maker
purple and lilac metalic 2CV(VIOLET)registered to her in doors
1972 DS special been layed up aprox 31 years
Duracell
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Re: Xantia rigidity regulator

Post by Duracell »

Sphere, electrovalve, hydraulic pipes from front corner spheres, another small hydraulic pipe(not yet traced) - apart from that nothing unless the casing cracked - but why only leak when driven?

Regards

Richard
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Mandrake
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Re: Xantia rigidity regulator

Post by Mandrake »

Are you sure its not leaking slightly when stationary with the engine idling ? First thing I'd be doing is cleaning up the oil to catch it in the act otherwise you're guessing as to where the leak is coming from.

There are a number of places where the Hydractive control block (rigidity regulator) could leak -

* The sphere neck (standard sphere seal)
* The two small 8mm union 3.5mm pipes (standard pipe union seals - one goes to the main high pressure supply for the electrovalve, the other to the height corrector via the anti-sink valve)
* The bleed nipple (only present on XM style regulators used in the S2 runout - it's like a brake bleed valve)
* The main 10mm steel unions that feed the struts (flared pipe union with NO seal, just metal to metal contact)
* The plugs into which the steel unions bolt into (large hex head - there is a large o-ring half way down the shank of the plug which is easily replaced if the plug is unscrewed)
* The base of the electrovalve (two small green o-rings, one of which would cause an external leak)
* The overflow return hose off the top of the electrovalve.

It could be any of those. On my two Xantias the only leaks I've had in the area are the main steel unions that feed the struts, especially the underneath one - they don't use any seal and I've found they can be quite finicky to get them to seal well after they have been disturbed - a bit of dirt or grit, poor alignment of the pipe into the joint, or under or over tightening them and they can leak.

If they are dribbling disconnect them (depressurised of course!) and give the joint a blast with compressed air and/or a good wipe to clean out any grit that might be in there, move the pipe around a bit to make sure it lines up square and carefully nip it up again without over-tightening.

It doesn't always seem to be possible to get them 100% weep free - both my Xantias have weeped slightly here despite my best efforts, but not enough to drip on the ground.

I've also read about the alloy around the base of the electrovalve (it's quite a soft alloy) corroding away until the seal can no longer seal, so that's another possibility.

I can't see any reason it would leak while driving but not while parked with the engine running - what about when the suspension is at maximum height ? That puts full pressure into the system so is a good stress test.

I think the only way you'll identify it is to thoroughly clean the oil up in the area then go for a quick test drive until you see evidence of oil. If you can catch it before it spreads that is.
Simon

1997 Xantia S1 3.0 V6 Auto Exclusive in Silex Grey
2016 Nissan Leaf Tekna 30kWh in White

2011 Peugeot Ion Full Electric in Silver
1977 G Special 1129cc LHD
1978 CX 2400
1997 Xantia S1 2.0i Auto VSX
1998 Xantia S2 3.0 V6 Auto Exclusive
Duracell
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Re: Xantia rigidity regulator

Post by Duracell »

Thanks for the information Simon and sorry for the delay in responding - I did not realize that the 10mm pipes were metal to metal seals - I have not had a chance to investigate it further and may not bother until it stops raining. I will clean it up again and attempt to see where its coming from but I can not visualize anything that would dump approx. 1.5 litres of LHM during a 10 minute drive and then stop leaking.

Regards

Richard
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Mandrake
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Re: Xantia rigidity regulator

Post by Mandrake »

Hi Richard - I can think of something that could leak a lot when the car is driving but not (much) when its stopped - the base of the electrovalve.

Download the Hydractive 2 training manual here:

http://homepages.igrin.co.nz/simon/imag ... ive_II.pdf" onclick="window.open(this.href);return false;

Have a look at page 15 of the PDF (adobe reader page numbering, not the page numbers printed within the pages) and you'll see a cross section of the electrovalve.

The high pressure supply (HP) goes in the left hand end of the electrovalve on the diagram and is supplied to the main control block where it says user circuit.

The small o-ring near the end seals between the high pressure inlet and the control circuit - this won't cause your problem. However the large o-ring seals between the control circuit and the flange of the electrovalve where it screws on.

If this o-ring is faulty or the edge of the flange is eaten away through corrosion (which can happen) then it would leak oil rapidly but ONLY when the electrovalve is energised, thus it wouldn't leak when the car is parked. It should still leak when the car was idling however.

Does the car switch properly between soft and hard modes if you do a bounce test ? A further possibility is that if the diode in the electrovalve is faulty (very common) then it will only actually engage soft mode (and thus leak) for half a second each time the ECU tries to switch the suspension from hard to soft.

So parked or idling it wouldn't leak, but as you drove the car triggering soft->hard and hard->soft transitions it would leak briefly during each hard->soft transition. As it switches mode frequently while driving (a dozen times or more a minute depending on driving style) it could explain a leak that only occurs while driving.

I'd suggest you first verify with a static bounce test whether soft/hard switching is in fact working, and then focus your search for leaks around the electrovalve.

To do a bounce test let the engine idle and bounce the front suspension - it should be soft. Then turn the engine off, close all doors and wait 30 seconds for a click, then bounce the front again - it should be much stiffer now. If you don't notice any change (and the rear suspension DOES change as it should) it usually either means the internal diode in the electrovalve is faulty or the hydractive regulator sphere is flat.
Simon

1997 Xantia S1 3.0 V6 Auto Exclusive in Silex Grey
2016 Nissan Leaf Tekna 30kWh in White

2011 Peugeot Ion Full Electric in Silver
1977 G Special 1129cc LHD
1978 CX 2400
1997 Xantia S1 2.0i Auto VSX
1998 Xantia S2 3.0 V6 Auto Exclusive
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