Sticking Hydractive valves?

Shaolin Twelve · Unread post by **Shaolin Twelve** » 23 Nov 2010, 23:17

I have a spare pressure regulator in my back room off a 1.9 Td, and there is another on my V6 (which I am taking apart). The one on the V6 is definately good as that had no suspension problems, so I'll try installing that first to see if there is any difference before I buy new spheres. From what you and Jim have described, it is looking like a pressure related problem. If that yeilds no change then it's time to hunt for a nearby lexia and find some new related spheres.

On a related note, can the security valves and anti-sink valves be bypassed? I never minded the way my old CX used to sink when switched off, and maintain that without the anti-sink valves the struts are less likely to develop sticking points.

Shaolin Twelve · Unread post by **Shaolin Twelve** » 23 Nov 2010, 23:18

Removed....double posting. Sorry

Deanxm · Unread post by **Deanxm** » 24 Nov 2010, 07:17

The security vlve should never be bypassed, it prevents complete hydraulic failure by stopping the fluid flowing backwards out of the suspension system if a pipe bursts or belt snaps.
You could remove the anti sink but you would need to fit an FDV to supply the steering and a single output pump, this is a lot of messing around though and will not cure the problem.

Good luck
D

Shaolin Twelve · Unread post by **Shaolin Twelve** » 24 Nov 2010, 18:33

Boo Hoo

Swapped the pressure regulator with the V6 one today and immediately noticed that the steering was much lighter at a standstill. Unfortunately it has made no difference whatsoever to the suspension, which locked into bounce-home mode after the second speed hump taken at 10mph (coming off the hump actually).

When I got it home, I pushed down on the rear to find that it was nice and soft, and went down quite a way with a single rebound which stayed soft. The front however seems to be where the problems are at. The front felt like it was in firm mode, so I lifted the bonnet, stood on the front and bounced it hard, it went rigid after the 3rd bounce, then went firm again.

I'm thinking that maybe, just maybe my front suspension spheres may be low on pressure as there is a marked difference between the damping on the rear compared to the front. I'm going to try swapping my V6 front spheres with my activa ones just to see if it makes any difference. I realize they are probably not the right ones (I think the V6 ones are softer), but if it handles the speed bumps without throwing a wobbly and making me look like a cuban drug lord playing with his Caddy air jacks, then at least that will help target the problem.

All my front and rear control spheres are new, but now I think about it I did quite a few suspension spheres on xantias whilst trying to sort mine over a year ago, and it may be that I thought I'd done mine (problem is the front ones look immaculate which may have contributed to the false memory of me doing them....well maybe). Well, we'll see, back to it tomorrow....*sigh*.

I hope I find it soon, the car is too dangerous to drive any distance, it bounces so hard when the problem occurs that I loose traction....and to top it off I think my clutch is slipping too!

A well might as well do the clutch when I convert it to a 3.0 litre.

Shaolin Twelve · Unread post by **Shaolin Twelve** » 24 Nov 2010, 18:35

Hmmm, seem to be getting double posts, sorry about that .

Unread post by **CitroJim** » 25 Nov 2010, 06:22

The V6 front spheres will be fine

there is so little diffference between Activa-spec. hydractive spheres and normal hydractive spheres that it's immaterial.

Replace your centre hydractive sphere as well, they can cause strange antics when low/blown.

Shaolin Twelve · Unread post by **Shaolin Twelve** » 25 Nov 2010, 17:27

Yes! Talk about a plonker, yup that's me! I've diagnosed and fixed several Xantias with worn out suspension spheres over the years, but when it came to my own Activa....well let's just say I must be a right tool.

After all the spheres I bought, all the bits I've swapped and replaced, hours of head scratching, it turns out it was both front suspension spheres......I thought I'd replaced them, but obviously didn't. Found my receipts from over a year ago eventually, and lo I'd bought all the control spheres, and 8 suspension spheres......the suspension spheres were fitted to my friends Xantias, and though I'd replaced the control spheres, I'd forgotten that I hadn't done the suspension spheres on mine, of course now I remember I took my car off the road just before I got round to doing it.

Still, now that the regulator has been swapped the steering and braking are much more responsive, so that wasn't a wasted exercise, and now my local speed humps are taken without fuss.

Thank you all for your help and experience, you really made it possible to get to the root of the problem quickly....of course if I had just done the suspension spheres in the first place.............still, in my defence, when I pushed down on the car with the previous spheres, it appeared to be working as it should. I think what's been happening is that they were partially worn. Just enough damping for minor road imperfections but not enough for heavier stuff, which was then causing the hydractive system to lock the front security valves (going from firm to hard).

Ah well, live and learn.

Thanks again all.

P.s Jim, I have taken off the throttle bellows for the cruise control, and have the steering column controls. The vacuum pipe from the throttle bellows goes well under the battery area, I assume to the device which controls the throttle bellows? Is there anything else I will need to complete the conversion?

Unread post by **CitroJim** » 25 Nov 2010, 19:24

Oh, that's great news

Excellent!

Putting a positive spin on things, it's been a useful thread with a little more information gained on the peculiarities of Activa Hydraulics and it goes to underline my belief that sphere condition is absolutely critical on an Activa.

On the cruise, yes, under the front nearside wing, high up, you'll find the vacuum pump. It's a bit inaccessible and access is a tad easier with the bumper off. It's held on by two small nuts. Recover the three pin plug and if it's not too corroded, I'd like it. Mine on Old V6 is a bit green... Effectively, it's mounted right underneath the whng where the battery tray sits...

The other bits are obvious, the ECU, the stalk and the dash switch. The Cruise relay is a violet one but if you're breaking the V6 you'll be keeping all the relays and fuses anyway.

No, on V6 breaking, there are a few things to be kept and offered to V6 owners and some parts are unique. This includes: struts, strut tops, gearbox and ecu (especially gearbox if good), the HP pump, which you'll need for the Activa conversion and most importantly if you do use the engine and HP pump in the Activa is to make sure you take the steering ram pressure regulator from the nearside chassis rail on the V6 and fit it to the Activa. If you don't, the steering ram will be blown to smithereens as all pumps except the V6 has an integral pressure regulator for the PAS. A V6 pump on an Activa should be good as it has a higher output...

Also, keep the cat. Basically don't dispose of anything until you've spoken on here!!!

Looking forward to hearing about the Activa conversion, again, lots of advice as I nearly did it earlier int he year and did a good deal of research... I was so tempted because I had a candidate Activa here at the time and all the bits of a broken V6...

Shaolin Twelve · Unread post by **Shaolin Twelve** » 26 Nov 2010, 11:42

Thanks Jim,

That's excellent advice, and I will be only to happy to make available any parts I don't need to other members.

That said, whilst I am in the process of stripping the V6 (still breaks my heart), I only have a couple of weeks left to finish removing everything I can before I have to have the body shell removed (not on my property unfortunately, or I would have more time). So if anyone needs body panels/doors/windows in deep green (all in very good condition) let me know asap.

The gearbox and related parts will become available as soon as the engine is out (if not this weekend the next), and it is a good one with no faults. I will be keeping all the parts necessary to do the conversion and extras like the light clusters, wiring harness etc as spares for the Activa, but of course I am happy to help out other members who need parts I have.

My V6 is on an R plate and shares the same looks as my activa (series 2 I think, should be able to tell from my forum pic).

Thank you for the advice about the steering rack, I would have almost certainly ended up with it blown without it, and regarding the pump, if it is higher output, then I will use it on the activa to improve the overall performance of the hydraulic system.

Again a genuine thank you for all your wisdom, without you I would have been really stuck particularly as Haynes and the like decided to leave out key diagrams and models from their manuals, and replace them with the words 'refer to Citroen dealer'.......these days and with our cars, that is the worst bit of Haynes advice any one could give (apologies to those very few dealerships that actually know about Activas).

I used to be a service advisor for a Citroen dealership, and back then the people I worked with were knowledgeable about every Citroen going back to Traction Avants, these days there are too many who barely even understand that Citroens use hydro-pneumatic suspension (well obviously not the ones that don't) not hydro-elastic, and of those that can tell the difference, even fewer seem capable of grasping the concept that Activa's have additional control systems, not just self-levelling...ah but I am preaching to those that already know

DickieG · Unread post by **DickieG** » 26 Nov 2010, 18:10

Shaolin Twelve wrote:Thank you for the advice about the steering rack, I would have almost certainly ended up with it blown without it, and regarding the pump, if it is higher output, then I will use it on the activa to improve the overall performance of the hydraulic system.

Only fit the V6 pump if the car has a V6 steering rack, just in case you were thinking of fitting the pump prior to the conversion.

Shaolin Twelve · Unread post by **Shaolin Twelve** » 26 Nov 2010, 19:20

Ta da......saved again, I nearly did that today but ran out of time, so that was perfectly timed advice. I shall hold off changing the pump until the activa has the V6 steering rack.

Thinking about it is it necessary to replace the Activa steering rack for the conversion to V6? If not, to prevent additional problems, I was thinking I might fit the V6 engine with the Activa pump, negating the need to swap the steering rack when I come to convert it. If it has to be done, then not a problem, though I am also wondering why the V6 has a higher output pump when it doesn't have as much work to do as the Activa pump?

I'm beginning to foresee much head scratching when it comes to repositioning various hydraulic pipes and the like, but I'm undeterred as it has been a long time desire to have a 3.0 litre V6 manual Activa, and I doubt I will get the opportunity to do this again.

On a separate note, Jim, I have removed the vacuum pumps from underneath the V6 battery box. I have 2 of them, one small, one large, both have connectors. I have cut both connectors out of the wiring loom with as much wire as I could (I hope the Activa has the right connectors under its battery box), so which one was it you wanted? Mine are only very lightly corroded and will clean up in a jiffy. Also, not quite sure how to connect the pneumatic hoses (I know the main one goes to the throttle bellows), as I found part of the hose (the smaller T junction hose) was split and not attached to where it should be. If anyone has a diagram of how the cruise control gubbins should go together I would be very grateful.

DickieG · Unread post by **DickieG** » 26 Nov 2010, 22:08

Shaolin Twelve wrote:Thinking about it is it necessary to replace the Activa steering rack for the conversion to V6? If not, to prevent additional problems, I was thinking I might fit the V6 engine with the Activa pump, negating the need to swap the steering rack when I come to convert it. If it has to be done, then not a problem, though I am also wondering why the V6 has a higher output pump when it doesn't have as much work to do as the Activa pump?

Personally I don't know why the V6 had a larger pump and have never read why that is the case unless it was due to the weight of the engine

Unread post by **CitroJim** » 27 Nov 2010, 17:38

There's no doubt the V6 pump is a stronger item. I went to see New V6 today and gave her a Citarobics session. She rises and falls at about the same speed as a sinker Xantia does.

I'm not at all sure the V6 pump will fit the 2.0 TCT engine and not at all sure the Activa pump will fit the V6. I'm pretty sure the mountings are different on the pump body.

Also, the V6 pump has a removable pulley whereas the Activa one doesn't. It seems a small detail but without being able to remove the pulley, the pump can't be fitted... Not with the engine in-situ anyway...

As far as I know, the Activa steering rack is OK for use with a V6 pump so long as you are using the V6 external pressure regulator but check with an authority like B L Autos to be sure. Be sure to rescue the rack and ALL rack piping from the V6 as it's different. The pinion valve feed pipe is unique (because of the external regulator) and so is the pinion return pipe. It's special to both clear the V6 exhaust and to prevent heat damage from same.

I'm confused on the two vacuum pumps. There's only one for the cruise control. This has two connectors; one is a three pin that looks like an H4 headlamp bulb connector and the other is a normal square two-pin job going to the dump electrovalve. I expect the other vacuum pump is in fact the carbon canister purge valve. Is it brown and has a two pin plug on it?

The split you saw on the tee-piece is a very common fault and is the No.1 reason for cruise packing up.

Whilst uder the battery tray, recover the autobox ECU. They're worth their weight in gold, as is the gearbox. Whatever you do, stash the gearbox as someone, someday, will be needing one. Good 'uns are valuable....

I have the diagrams for the MK2 here:

Schematic Circuit

Harnesses

and finally,

Component Locations

The MK1 cruise has subtle differences. If you need the MK1 details, let me know...