Hydraflush And "hydronet 2000", ...and the happy ending of an Odyssey!

I'm puzzled now. Aren't we all agreed that hard mode just alters the sensing speed of the electro valves and at standstill (S2) the suspension is still in soft mode. Why then is it not possible to gently push the front suspension down? Is it really that sensitive that any movement at all puts it immediately into hard mode?

I think they mean after you park the car & shut the doors?.

30 secs of soft (electrovalves open) then the clunk into hard mode.

The only way of getting into hard mode at standstill with the engine running is to remove the hydractive ECU fuse.....(or have a broken hydractive system ).

Mine in hard mode gives about 2" of movement at the front and about 3" at the back. In 'normal' mode about 4" front and 6" rear. (Now its working).

Peter.N.

HAHAHAHAHA!!

C'mon all of you , don't make me post another nude of myself but...20 years posterior to my christening, to put things back in order!!

Demag, u r right but they've been trying by removing the relevant fuse in the cabin fuse-box, so suspension ECU remains without any current at all, so car is permanently "hard".

OK, said I don't have time but have toi report this as I got the news today from my indy. So, what happened: rememebr last week or so, some evening I tried both reversing combined with hard bracking, and then did about 10 up/downs with suspension in permanent hard. Well, as I've written in this thread, one or both of these actions seem to have totally unstuck my rear suspension, just immediately. Going back home, I realised Iv'e passed a couple of spots where I'd excpect a "thump" from the rear, and I just didn't feel anything. Now it seemed the *front* was harder -as it should really, the rear is so soft on hydropeumatic Cits-!! Unfortunatelly I cannot say which action did it. I didn't report extensively as I wanted to confirm results for a week or so. The only thing I wrote was that after doingthe ups/dows, the pressure regualtor started cycling all too often -10secs when it was 20+ just before-.

So, a leak developed. Next time I took the car, it had poored lots of LHM on the street. First meters driving, pressure lamp comes on and I decide to stop: had lost plenty of oil. Anyway, I filled it up, decided to drove to my indy -with the fire extinguihser next to me!- and gave it to him.

My fear was that the extra back pressure created by the up/downs -obvious from the slower rise/bottoming of car when in hard mode- blew up something before the hydractive blocks. I thought the DIRAVI had started leaking -this simply means to throw away this car- so I passed a couple of scary days before I hear from my indy-.

Thanks god, all it was was a plugging fitting I had used in a modification I had done a year ago: to make sure the electrovalve doesn't leak back in case the overall wear of the system was high, I drove a pipe from after the pressure regulator directly to the front e-valve, through a one-way-valve. This had 1 inlet and 2 outlets. Obviously I didn't need 1 of the outlets so I blanked it with a standard 3.5mm fitting, in which I had normally placed a cupronickel pipe, but I had cut it and folded it 2 times and pressed this in the vice till it couldn't shrink more. So, the pressure from doing ups/downs in hard modem, has blown a hole at a folding point of that pipe!! Unbelievable. and I've been doing normal ups/downs for the last year and 6,000miles.

This tells me that I have to warn you that there's a risk in doing ups/downs in hard mode. So do it at your risk. I repeat, this pipe blew just after 1 session of these ups/downs.

Another problem in the process is that my car is now filled up with 100% LHM. Unfortunately the rear has retunre dto its previous state -and it looks worse with LHM-. Still waiting for the LHM to settle down and I'll report later. I'm stopping the experiemnts for now as I have a very important milestone for the end of April, and then will start again -I'll sure repeat the ups/downs in hard mode as I believe *they* were responsible for unstucking the rear suspension (that's because I did again a violent braking in reverse session yesterday, and there was no difference whatsoever -my regulator ticking time is again abck to the usual 20+secs after leak was repaired-).

cheers
George

As George says the car is forced into hard mode. However on mine I unplug the ECU, I've tried the fuses that are listed in the handbook but the feed to the electrovalves was still live (I knew this because my hard/soft status LED was still lit).

Anyhow when's the next full moon.... Even Peter's joining in!

Thought for the day - can you back flush a strut using the return pipes? I have a spare pair in the garage so I may try it.

Steve.

Guys, check out the new link at my signature, a 2.5td year 2000 from a member of planete-citroen...almost gave me seasickness, so wallowy it is!!!

Ok, in summer I'll seriously deal with my suspension's issues. Mine perhaps has a similar travel but the freedom of moving is definitely not there.

cheers
G

This post has been edited by jorgy9 on April 02, 2008 05:15 pm

I resemble that remark If you saw my post re suspension problems on mine, you may have noticed a sure fire way to tell if the electrovalves are working or not, the fact that you can hear the buzzing, or it's really a whine, 1000hz, doesn't necessaraly mean they are open. You should hear a definite 'clonk' as they open, followed by the whine, and the another 'clonk' as they shut, about a minute after closing the door or whatever. Mine were clonking when the door was opened and they switched on, but not when they switched off, so no soft suspension as they were actually closing almost immediatly after they opened - reason? defective diodes in the solonoids.

Right, I will go back to sleep now.

Peter.N.

Was that XM fitted with comfort spheres do you think?

Steve.

Not as far as I know, I'll ask the guy. He got it right with the help of the other guy whose car in on the first video.
G

Very interesting. Does the first guy say how he fixed his?

Steve.

As far as I remember they both had pretty standard problems, eg diodes, spheres etc, not even something presssure-related. They both have run Hydronet which -they swear- brought the final blow to the stifness. In my car all this and more has been done and it's a mystery why the susp it's not performing like theirs -a "mystery" I say, anyway there's nothing mystirious, just something I've not found yet-. At the end I'll start replacing parts with new till it performs -what I'll do before, in summer, is check the return pipes one by one, I've been postponing it for ever-. On the other hand, my steering is today, with fresh LHM, better than it has ever been, like new I imagine, so this shows it's a localised suspension-related problem.

Personally I estimate in most of your XMs that don't go well, having repaiered all other things, it will be the low pressure effect (regulator), this is what instanltly fixed mine which is far older&worn than most S2s here, now, what hapenned to mine the day I bled the brakes, *this* is the "mystery", but hopefully none of you will have anything similar.
G

This post has been edited by jorgy9 on April 02, 2008 09:56 pm

Evening all
I'd just like to say how absolutely fascinating it is reading this and the other threads running on the hydraulic forum. It's really absorbing following these discussions and then listening out for all the pops, clicks and hissing when I'm playing about with my XM. I'm pretty sure there's a couple of spheres that could do with being replaced but even so it's still the most comfortable car I've ever owned. Anyway, carry on

Bob

Lucky you Bob!

G

Ok, so this guy with tehe grey 2.5td XM has answered that his corner spheres are from Citroen and his middle are IFHS. So, no, it's not comfort spheres....It's not even my spheres -which must be AMTEX or something- as they gave an amazing ride a couple of years back -and the front ones still give a good ride-. Just my rear suspension having something else. I should check the rear spheres though, who knows perhaps one has exploded -although this would be very obvious when car passes momentarily in hard, the car becomes like a cangoroo, had this with one front sphere-. Plus it's extra soft in other occasions, e.g. it crashes the rear when starting from a traffic light. So no, the volume is there. Something else doesn't allow the cylinders to move fast enough. Perhaps I should start thinking of rear arm bearings, although again they've been perfect 2 years ago and no sign now of them being worn -noises etc-.
G

George - if your car squats when you take off from traffic lights then that seems like your rear electrovalve is not closing properly when you plant your foot on the accelerator?


My understanding is that the only differences between comfort spheres and normal spheres is the internal nitrogen pressure - comfort spheres are higher pressure.

f you had the luxury of a sphere charging rig (I haven't ) I suppose you could make your spheres to any specification between normal and really soft by just varying the sphere pressure. Is this too simplistic and am I missing something?, perhaps Noz & Co could comment.

I know it's not big and probably not clever (time will tell), but the ride on both my driveable cars is super soft at the moment, with the hard mode coming in noticeably and as normal. The saloon has a mixture of aircraft hyd fluid (80%) petrol (10%) white spirit (10%). The estate has ac hyd fluid (85%) petrol (15%). I cleaned the filters again last night and loads more black silt had been deposited in the reservoirs. I'll continue with these mixtures until either the summer or until the silt deposits decrease.

Yes, every residential street has one........I'm that bloke who tinkers with cars and always has his bonnets up!! Perhaps it's 'cos I don't care much for TV ball sports, alcohol or gardening - I find enjoyment in just tinkering.

Both hyd systems appear healthy judging by the tiny amount of fluid in the return pipes and my cars bounce like the french car in George's youtube video links.