1992 XM 2.1L, TD, 5 speed, Hard suspension, hard steering

[citroens]

Hi Folks,
I was relying on another list for my troubles, but not much as in answers, so here I am.
I have had this Lhd, wagon,2.1.TD,bought from Oxfordshire, it had 350K Kilometers, the camera belt was replaced at 327K Kilometers, just last year and shipped it to Canada. It's ride was rough when I had seen the car, psssss, hissing coming from around the regulator or the fdv. Had all the spheres replaced by Pleiades, but not much difference in its ride, still it drove unlike a Citroën.
Since coming to Canada, it , I had removed the reservoir and emptied it, cleaning all the filters, and filling it with the Total Rinsage, drove it for 5000 Kilometers, before putting LHM plus into the system. It drives okay, but still hard, the Electrovalve impedance was checked, good, it's plug connector cleaned and fitted, checked ok, all the grounds are good too, now that they are soldered with the ground eyelets fitted to the front fenders.
What is happening:
Engineer started from cold, the rear height goes up, the front takes a while before it comes up, when the lever is put at the lower setting, the car is very slowly come down, the steering is hard, but softens upon doing highway speeds.
FDV recently replaced, steering feel varies with speed.
The PR hisses, all spheres removed to verify their pressures, all 100% good, what to check next?
I suspect the height both the height correctors, along with the Pressure Regulator.
Also noteworthy,
The hp pump charges the system every 30-35 counts, but the PR hisses, the car rides hard.
I will remove the height correctors and clean them, assemble them, also the pressure regulator.
Anything else?

[noz]

Hi Citroens,

Maybe the answer to your problem lies here:

http://club-xm.com/forum/index.php?showtopic=845&hl=diode

or here:
http://club-xm.com/forum/index.php?showtopic=1747&hl=diode

or here
http://club-xm.com/forum/index.php?showtopic=1536&hl=

cheers

noz

[citroens]

Thanks for the pointers,

My problem isn't related to the switching of the electrovalve, rather a problem of the hydraulic system.
I would probably need to vacuum the whole hydraulic system, then bleed the system as per the service manual.
Has anyone done this before?
I need the flow diagram of all the hydraulic components for my RP 5782.

http://www.autoweek.com/article/20130718/CARNEWS01/130719838.

Sincerely

Prakash

[xmexclusive]

Hi Prakash

From your description you have flushed the hydraulic system fairly well.
I very much doubt that more intense flushing will make much difference.
I do not see any checks or measurements made of hydraulic system pressure.
Getting these right can be critical to making the suspension work correctly.

Tracking down the details of your version of the XM will be difficult from UK information.
It may be that the diagrams in the French XM workshop manuals will be more help.
Let me know if you or your engineer can read French.
It would be very useful to know the VIN of your car.
Aluminum plate with embossed lettering found over top of engine fans.
Number I need will be in the series: VF7Y3xxxxxxxx0000
VF7Y3 = Citroen XM series 1
The xxxx's define the specific model type of XM.
This info may help get the right information for your car
The final 0's are the series build number for that particular model.
This last info is not needed.

John

[citroens]

Hi John,
This XM Diesel's RP number is 5782, it's VIN VF7Y3AT0001AT3285.
A few weeks ago, I replaced the FDV with one that was fully refurbished, there isn't a lot of difference in its ride or the steering.
The brakes may have improved marginally.
I would have liked to attach high pressure gauges from the HP pump, going into the FDV, same again to and from the Pressure regulator, to the brake block and the suspension, also to check the low pressure lines, but I no not have the 3 way unions,just waiting for various sizes to possibly get from a hydraulic fittings place.
There again I am not sure of the thread pitch and the size of the threads for the various fittings, I 'd have to measure these individually.
I believe the pressures will most definitely point me in the correct direction.
I suspect that either the HP pump is weak and or the PR have an internal leakage.
Or maybe the height correctors are semi-ceased.

I am looking forward to troubleshooting this vehicle, knowing that it should be as smooth as my 1990 sedan V6 Deravi Automatic.

[xmexclusive]

Hi Prakash

That information confirms the system fitted is the final version of XM Hydractive.
Cut over to Hydractive 11 (ORGA5929) was around 5 months after your Break was built.
If not already done I suggest you check the pump belt tension and the flow on the individual hydraulic returns.
Belt slippage is a common cause of low pressure on 2.1's.
Each component in the hydraulic system has its own return pipe into the resovoir.
Excessive leakage (more than a few drips) can identify which component is leaking LHM and so dropping pressure.
I may be able to recover a few Tee pieces from a scrap car to send you.

John

[citroens]

Hi John,
Although my XM Break is a 1992, it stayed in the dealers lot for some time, until it was first registered to it's new owner and not until 1994.
With reference to the Factory Service manuals with flow diagrams and the mechanicals(excluding electrical) I have bought the complete set from the UK, hence it is in English, all with 3 x binders, including any updated TSBs, added to the final binder, the whole lot weighes over 8.5 Kilograms. It is sitting at my sister's in Herts,England, until I come over for a vacation. Until then, I could use any help that I can get.
The belts were replaced at the same time as when the Cam belts was replaced, also checked by hand,it seems tight, though what is the tension supposed to be?
It have a single electrovalve at the front centre sphere, distributing pressure to the centre rear, so it must be a MK1 Hydractive, also the Hydractive module that is in my (RP4964) 1990 sedan V6 with the Deravi powered steering, these Hydractive modules are exactly the same, as they interchange.
If the system is losing pressure, then
it doesn't make sense as to why the pump is only heard every 32~35 counts?
I propose to check the low pressure leak through rate at all the 4 corners and or wherever I see a return that may be going back to the reservoir. I can obtain these push fit, 3 way nylon unions locally.
The ones that I am in need of are the high pressure ones.
I live in Ontario, Canada.


Many thanks

[xmexclusive]

Hi Prakash

Sorry if some of the questions are covering the simple checks that you have already done.
Just need to get things straight in my mind to know where to suggest.
I have a full set of XM binders in english here.
They are very useful but not easy to work through.
Despite very limited French I make a lot of use of the RTC books that I have obtained.
For example the coloured diagrams of the Hydractive systems are worth the book price alone. The table of different models by VIN enabled me to check on your break.
Some of the wiring diagrams are easier to refer to than the Citroen ones.
Then there are lists of model technical changes by date.
If you PM me your email address I will see if I can scan and send a few relevant pages.
If you find them useful then I can tell you where to obtain copies as they are still available.

Tell me a little more about how the power steering fails to work correctly.
This may be because of a fault in the rack hydraulics.
It could be low hydraulic system pressure as the power steering drops out first by system design.

You need to consider that an XM break has a different rear suspension from a sedan. It is optimised for quite heavy loading.
In preserved use the break rear will generally operate right at one end of the design range while the sedan will be operating at close to optimum.
When you get to fine tuning the break suspension some changes from standard might match sedan ride better.

John

[citroens]

Hi John,
No worries, I understand that you need to know fully well, what checks I may have carried out.
I like the colored drawings in your RTC manuals as well as the fact that you are able to check more of the car in question via its VIN number.
A long time ago, I used to repair consumer as well as industrial electronics and I used to find following the circuit diagrams with the schematics drawn, using colored lines and the components. Bang & Olufsen service manuals were like that back in the seventies and the eighties.
Okay with reference to the power steering, this is what used to happen.. When the car was initially started from cold, suspension at the rear rose to its height in normal position,very slowly followed by the front suspension, but very slowly(you can have a cup of tea and momentarily get lost in your thoughts in the meantime)it would have already come to normal height, but the hissing from the front, probed and checked via using a mechanics strethoscope, touching each and every components in the hydraulic system, this hissing noise came from the Pressure regulator.
On the road, the steering would operate with power, though I don't really know how the Dirass powered steering is supposed to feel from the point of power, as this is the first Citroen that I have got without a Deravi power steering,( my 1988 CX TRI, My 1986 Dovrin and my XM Sedan all have deravi powered steering, except my 1971 D Super).
Okay, on the highway, this is what happens, when the car is driving through a straight through road, without any bends, hence the steering is basically pointing straight, the suspension feels a little afloat, though as soon as there is a bend in the road and or I am changing lanes, the suspension becomes deprived of the high pressure fluid(missing the shock absorption component), as the steering wheel seems to get a priority over the suspension or the brakes, this I have experienced both ways, going to Saratoga Springs, New York rendezvous a few weeks ago as well as coming back.
Also the steering misses a beat or two when I am around the bend, trying to stay within the curved road markings, it's almost like a tug-o-war, but otherwise the steering is okay, only lacks the power assist at times almost like the system pressure is deprived and or not enough to supply the whole of the hydraulic system.

Also, I haven't yet figured out the personal email. But if you were to add an at sign after my handle + rogers dot com.
Many thanks again

[citroens]

Hi John,
I did check for the drip through rate from the low pressure lines, though I may have done it differently as I do not know any better way.
Started the car, placed the height lever to the highest position, removed each low pressure lines going to the reservoir, attached this instead to a hand held vacuum pump, applying 6bars of vacuum- nothing not even a single drop, tested all the 4 corners, absolutely bone dry, moved the suspension to the normal height, now there is something coming out, then stops.
I am not sure about the pump out put, maybe I will get all the various connections made locally.

Prakash