Xantia: Frequent Regulator Clicking - Leaking Doseur?

swiss_steve · Post by **swiss_steve** » 02 May 2007, 08:18

Hello All,

Can anyone help me with this small problem I've got:

I've recently (within the last 4 weeks) changed all my spheres, Hydraulic Regulator & Hydraulic Pump, and renewed the LHM fluid in the system, but still I have the Regulator clicking every 5 seconds, or so (starts off at about every 8 seconds when starting from cold, then goes to about every 5 or 6 seconds when warm). Most of my driving is motorway cruising...

I had the accumulator sphere and regulator checked out by the Pleiades boys, but they're all exactly 'on spec'.

Is there a possibility that the Brake Doseur is leaking? When I have to brake firmly, there is a 'squelching noise', and if I have to really brake in emergency, a slight pulsing from the brake pedal. I'm wondering if there may be some kind of leakage from the Doseur back to the Regulator, causing the frequently cycling....

The car in non-hydractive (if that helps).

Any thoughts or ideas would be welcome.

Cheers,

Steve

jeremy · Post by **jeremy** » 02 May 2007, 08:27

Or could be the non-return valve in the regulator is leaking. This can be repaired at no cost - and you will find full instructions on this site.

swiss_steve · Post by **swiss_steve** » 02 May 2007, 09:08

Hi Jeremy,

Pleiades checked the Regulator out - all O.K. The Acc. sphere was also 62 Bars...

Curious eh?...

Post by **Peter.N.** » 02 May 2007, 09:17

...Or it could be a leaking distribution valve or several other things, I have the same problem with mine and have not found it yet. I swapped the regulator and distributer for secondhand ones but I am not convinced that they dont have the same problem. Try disconnecting the return pipes to the reservoir one at a time and see which is returning a lot of fluid, if you find one, follow it , or at least try, and it should lead you to the culpret. But try what Jeremy says first.

Post by **CitroJim** » 02 May 2007, 09:22

Yes, curious. I'm with jeremy on this, the regulator is the first suspect here. How was it tested for Pleiades to be confident it was good as the return valve problem would not show up on a simple pressure test.? A ball reseat is worth doing in any case.

I take it your car has the 6+2 pump so PAS and the FDV issues do not enter the equation here.

A rough check can be carried out on the doseur by slipping off its leakage return pipe and seeing how much LHM it is returning. If it is a huge amount then that'll be it but somehow I don't think so. It's normal for them to "squelch" under heavy braking. Both mine do. Ditto the "pulse".

Other than that, it'll be a case of going around all the leakage returns and seeing which is returning an excessive amount.

Post by **CitroJim** » 02 May 2007, 09:24

Sorry to Post almost the same as you Peter, we must have both been typing at the same time!

swiss_steve · Post by **swiss_steve** » 02 May 2007, 09:42

So guys, you think the brass punch on the ball bearing may be worth a try, despite the regulator being a brand new overhauled unit in March and checked 2 weeks later on the bench? I guess it won't take long or do any harm...

My car has a hybrid system of components because it was built at the factory in October 1997 and is the very last of the pre-facelift (MKII) models. It has Air-Con fitted.
As such, it has the later version Hydraulic Regulator fitted (I know this because the union of the main pipe from the Hydraulic Pump didn't fit the older style Regulator that I was initially supplied - it has a different pipe seal; like a cone instead of a straight piece of rubber hose).
The Hydraulic Pump is a standard three port pump (one supply, and two outputs - is that a 6+2?), but with a smaller pulley than earlier models (again, 'discovered' due to trial and error), perhaps because of the Air-Con.

Checking out this quantity of leakage return seems, on the face of it, to be a non-precise science. Firstly, how much is an excessive amount? What is normal?
Do I assume that you hook up a long clear tube back to the reservoir to check this out?

Sorry, I'm not an expert on this stuff, but I'm gradually getting wiser on these systems, mainly through trial and error!

Cheers again,

Steve

jeremy · Post by **jeremy** » 02 May 2007, 10:23

The return flow from the doseur will be a matter of judgement - but have a look at it first. If its minimal - it won't be the problem - if its a substantial flow it may be.

Its not unknown for accumulators to be defective when supplied. A good can be checked simply by running the car at normal height for a couple of minutes, then turning the engine off and sitting in the boot. The car should sink a long way - then after about 30 seconds - rise again.

You can eliminate the suspension by dropping the car fully so as to close the height correctors and seeing if the cycling rate changes.

My suspicion is that re-seating the non-return valve is the major part of regulator reconditioning. Of course its dismantled, cleaned, resealed and painted but the secret ingredient is re-seating the ball.

I suppose the ball under the pressure relief valve is still there? It should be unless the bolt has been removed.

Any possibility of air getting in before the pump? The hose from the reservoir and its connections would be the culprit here. The connections should be sound and tight with replacement clips if its been disturbed.

swiss_steve · Post by **swiss_steve** » 02 May 2007, 10:49

Hi Jeremy,

I'll check out the doseur return flow this coming weekend....

Curious thing about the Accumulator; here's my symptoms:-
When the car is set to normal height and I load the boot (with heavy items, or myself) it drops - but it doesn't push me back up, it just stays there (remember, all the spheres are new). If I move the height control lever in the car, nothing happens.
When I remove the Acc sphere, I get a trickle of LHM come out. Then, when I replace the sphere, then take the car the normal or max height then turn the engine off, I can get the car to drop down to normal or minimum just by moving the height control lever without having to start the engine again.
However, after the car has done a journey, its back to the sitation where the car won't settle by just moving the height control lever in the car - you have to run the engine again.

Is this all connected, perhaps?....

I assume the ball is actually there - I can't believe Pleiades would overlook something like that...

jeremy · Post by **jeremy** » 02 May 2007, 12:28

Sounds like a flat accumulator to me if it won't rise. To see what should happen do the same test with the engine running.

You will get a trickle of LHM when you remove the sphere - its simply siphoning through the pump.

I'm not familiar with Xantias but I think some of your suspension problems sound like seized height correctors. They may respond to lubrication but be careful to allow enough room for yourself if the car should fall on its suspension. These cars can kill.

swiss_steve · Post by **swiss_steve** » 02 May 2007, 14:27

Thanks Jeremy,

If you put a heavy load in the boot of the car (engine off), the back drops and stays there until I start the car, then it lifts normally. Surely, this is an indication that the suspension system is "generally" working properly, including the height correctors (which always puts the car back on an even keel, no matter how much heavy weight I put in it - I often carry 150Kg in the back of my Estate, so you can see why I need a car with self-levelling suspension

).

The general ride with the new spheres is once again superb.

Pleiades checked the Acc sphere and definitely confirmed there was 62 bars in it....

The height correctors do move, albeit with a little bit of pressure at the end of travel on the height control lever in the car. I try to lubricate them occasionally, especially the rear one, but it's a fighting battle against the elements.

I think I'd better try re-seating the ball and looking at the return flow on the Doseur first....

jeremy · Post by **jeremy** » 02 May 2007, 16:04

If the accumulator is sound the car should rise.

There are 3 ways the LHM in the accumulator can go. Onwards to the rest of the system is the correct one, down the piston / shuttle in the middle is a possibility but rare and back the way it came via the non-return ball valve.

If the car won't raise itself shortly after turning the engine off then there is something wrong with the system in that there is no reserve in the accumulator - which is due either to bthere being nothing there in the first place or it leaking rapidly.

Incidentally a flat accumulator may produce a very short cycling noise (did on my BX when it went prematurely last year - but BX have single outlet pumps and so more is available for the regulator) and may also mean that strangely the warning light goes out quicker (as there is no gas in the accumulator to compress)

swiss_steve · Post by **swiss_steve** » 02 May 2007, 16:25

I absolutely agree with you Jeremy. I've researched this site and carefully followed all posts regarding pressurisation problems and all point towards the Accumulator or Regulator. The fact that I've renewed both and then subsequently double-checked them both (by Pleiades) after their installation baffles me, hence to post to pick other people's brains to see if there's any other potential factors that may be in play here.

So I'm at a bit of a loss as to what next, but will try the previously suggested remedies - I've got to try all sorts or my new Regulator will be worn out in no time...

Mandrake · Post by **Mandrake** » 03 May 2007, 03:36

Don't expect the accumulator to be able to lift 150Kg in the boot (with the engine off) - it probably won't. It should be able to lift an average 80Kg bloke though

Regards,
Simon

citronut · Post by **citronut** » 03 May 2007, 18:50

if you get patering at the brake pedel this is usualy down to air in the brake system,this is normaly caused by one or more of the spheres dumping or looseing gas into the fluid circuit,also im not sure on the xant but on a BX you can test the AC sphere with car at normal hight just after engine has been shut off,move the hight lever to the highest setting and the car should rise a bit,this shows some reserve presure in the AC sphere
regards malcolm