Xantia Suspension Woes! S1 and S2 MOT Failures

[Rhothgar]

Evenin' all.

Had a nightmare of a week. Both Xantia failed their MOT. Stupidly, War Horse didn't need doing until 14th April but I thought it was 4th April it was due and so took it earlier than needs be.

S1.

Suspension solid all round!

S1 Failure Sheet

It's not actually solid all round but it is hard. Front offside is fine.

I checked the sphere pressures yesterday and found I had 65 bar in the fronts and 20 bar in the rear. Again, trying to do things from memory is letting me down of late. I thought the rears should be 28 but it turns out, upon checking today, that the central sphere is 28 and the rears should be anywhere between 30 and 40. So I topped the spheres up to just above 40 as there is a 5 upwards tolerance.

I left the Tecnosir connected and had some lunch. The pressure in the central sphere was still 30 bar upon my return. I could say there that the diaphragm, you would think, must be OK. Or is it? The wheels were not loaded and the system had not been reprimed. Still! You would expect some lost of pressure even without load on the wheels.

Checked the fronts and they were a little high at 65 bar.

Strangely, I couldn't make out if the regulator was clicking. I sat in the car and tried to focus but I simply couldn't pick up ANYTHING at all!

I plusgassed both height correctors and the suspension goes up and down as it should apart from there is a sort of twanging sound when the rear drops.

For me, both the front and the rear look too high to me. The rule of thumb is 3 fingers at the front and one at the rear. Well there's more than that for sure.

So my question is how can the height setting go out of kilter if you have not touched the settings?

The dog bones are both intact.

I have read a few posts on here tonight to refresh my memory. One about a C5 X7 is not really applicable but there was one from about 13 years ago talking about air in the system.

So! As I understand it, the rear centre sphere is simply a reservoir for braking backup so this shouldn't affect rear suspension softness.

The regulator should click every 30 seconds or so. I think mine when I last listened to it and could actually hear it was around 90 seconds so in good health. Now I am actually left wondering if the accumulator sphere has burst internally because the regulator is not clicking. I cannot recall if it clicks at 170 bar or at the lower 140 bar limit. My guess is it is supposed to click at the upper limit and therefore the system is not getting to that pressure and hence not clicking.

If I am correct on that, then why isn't it clicking? Where can I look?

I only have tomorrow and Monday to investigate this further and then I am in hospital on Tuesday for a biopsy. I am not sure how I will be feeling afterwards so if anyone can home in on what I need to check to maximise the time I have and for me to use it well it would be much appreciated.

There will be a leak somewhere I believe but it isn't obvious if there is one. The car has only done 190 miles since last MOT and I am wondering if the rear rods have seized to the rear spheres. It's all looking very rusty around there. The R-clips in particular do not look as though they will survive being removed.

S2.

One at a time to avoid confusion. The nearside front leak was thought to be a pipe above the rack but the LHM was on the rear of the crossmember (which has a raised ridge) so it cannot be coming from a pipe in front of the crossmember. The padding on the bulkhead is wet on the nearside. I had a moment of clarity on Thursday night thinking it was the same pipe that the additional coolant heater had previously burnt through but I was wrong. I figured that if the padding was wet then it must be tracking down the bulkhead.

S2 Failure Sheet

Of note, obviously they don't really know if the pipe is suspension or brake (unless it's obvious - you cannot expect a tester to understand the Citroen hydraulic system).

[mickthemaverick]

Not the greatest results there Roger, hopefully the hospital won't incapacitate you. I cannot offer any sensible comments having only had the Activa which was different!!

[RichardW]

S1

If it's running too high it will be hard. Is it a VSX with hydractive? Twang at the rear could be seized rear arm bearing, this will certainly affect ride quality.

S2

The anti sink valve under the tank is a known leak point, the o ring fails under the blanking cap.

[Rhothgar]

S1

If it's running too high it will be hard. Is it a VSX with hydractive? Twang at the rear could be seized rear arm bearing, this will certainly affect ride quality.

S2

The anti sink valve under the tank is a known leak point, the o ring fails under the blanking cap.

Sorry. I should have made it clear. No. It’s non-HA on the S1.

I found the front height corrector was VERY sludged up. It’s in a horrendous state. Dare say the rear HC will be the same but now I have the front HC off, I will clean that up and bang that in the rear.

Like a buffoon, I started the car and put the suspension on high after having cleaned out the filters and the reservoir and did a session of citaeorbics. Probably just jumped loads of crap back into the reservoir. I should have bled all the brakes whilst it was on low.

Not sure if you can bleed the circuits if the regulator screw is undone. That would have stopped crap getting pumped back up to the reservoir if it’s at all possible.

I’m at a loss how to proceed really.

The rear HC will get done. The cylinders on the rear spheres have very corroded R clips so I am loathed to touch them else that is going to change into an engineering job of some proportion I fear.

The ride height definitely looks too high but I’ve not changed anything.

I was wondering if I should disconnect all pipes and blow them through with compressed air. I’ve no idea how the anti-sink valves work or other connectors on the circuits and I don’t want to create unnecessary work for myself.

On the S2, someone else has mentioned the anti-sink valve under the reservoir to me. Daft design as usual. Take reservoir out and there it is. However, the bolt is accessible from underneath!!!!

I think I should turn my focus to the S2 as I have a feeling it will be an easier fix.

[Rhothgar]

Going to buy 20 litres of the Triple QX LHM on Ebay for £55 delivered. That will be enough to thoroughly flush the system.

Read today that Hydraurinçage has not been available since 2012 and the general recommendation is to flush with LHM.

VERY tempted to add some 250ml of 99.9% IPA into 5 litres to help flushing.

[myglaren]

Have you seen Malcolm's restoration of gummed up height correctors?

[Rhothgar]

Have you seen Malcolm's restoration of gummed up height correctors?

Not sure. I may have in the past. Do you have a link to it Steve?

[myglaren]

Have been looking for it but not unearthed it yet
Hasn't shown up in the obvious places and he has 10,500 posts approximately.

[xantia_v6]

The height a Xantia should be checked with the engine running, they often sit high after the engine is switched off.

[Rhothgar]

The height a Xantia should be checked with the engine running, they often sit high after the engine is switched off.

.

Thanks for clarifying.

Not checked actual height yet as I have only just found the equation and diagrams but I do know they are high. Don’t know why they are because I’ve not touched them so avoiding adjusting until both height correctors are clean and fluid changed.

I can only assume regulator is not gunked up because of the pressures involved.

Just need to work out which poor fills the HP pump, disconnect it and check it’s clear. I guess the rubber pipe to the HP pump is a low pressure return and not a FILL pipe.

[Stickyfinger]

Yes, hard lines are high pressure lines. (the only exception really is the power steering that has a rubber section in it but the end connections are metal (but that is not pump fed).

Always release the clamps first before disconnecting them and take images/make a close notes of the spacers/stand-offs and how the pipes thread past other pipes. ANY tension when refitting is a BAD THING, they need to be a PASSIVE fit or you risk stress fractures in your pipes.

Being high, I would look at the height correctors and their linkages..........

[Rhothgar]

Cheers Alasdair.

Just had a quick chat with Martin at Pleiades. He was saying that the actual linkage between the dog bone and the anti-roll bar can break through work hardening. I’ll check that but as the height correction works he reckons the linkages are the likely culprit.

The front one was rather gritty in operation so I suspect the rear will be too!

Funny you should mention pipes. I read a post of mine from 15 years ago where I got them switched and the car was see-sawing!

The whole system needs flushing through. He mentioned a flushing oil but I neglected to ask him what he uses seeing as hydraurinçage is no longer produced.

[myglaren]

Have been looking for it but not unearthed it yet
Hasn't shown up in the obvious places and he has 10,500 posts approximately.

Found it, and it wasn't Malcolm who posted it:-

Removal, Cleaning and Refitting of a standard Xantia Front Height Corrector.

[Rhothgar]

Have been looking for it but not unearthed it yet
Hasn't shown up in the obvious places and he has 10,500 posts approximately.

Found it, and it wasn't Malcolm who posted it:-

Removal, Cleaning and Refitting of a standard Xantia Front Height Corrector.

Thanks mate.

I bet you found it just as you got to the 10,500th post too...

[myglaren]

Not quite, had done about thirty pages and had a

moment.