Depressurising The System

[kiwi]

Hi all,

The FDV (at least I think that is what it is) on my 2.0sei has started to leak a little, so I am thinking about swapping it with the one on my donor V6.

This will be my first foray into the hydraulics. I read somewhere that the car needs to be going to depressurise the system, and my query is this - The V6 has not been started for about 8 months. Do I still need to depressurise it or will it have depressurised itself over time?

Regards,
Kiwi

[Peter.N.]

Hi Kiwi

It probably will have but depressurising is a straighforward procedure. Look at the bottom left hand side (sitting in the car) of the engine compartment and you will see the accumulator sphere and regulator, bolted to the engine, just below the sphere on the body of the regulator is a 12mm bolt, facing forwards, all you need to do is slacken this by about one turn, dont undo it much more than this as there is a ball bearing behind it that can fall out. When you have finished what you are doing, just do it up again.

Peter.N.

[UFO]

You will have to have the V6 on stands etc to remove the pressure reg, unless you have already done some major part removing such as radiator, nose cone etc etc. You will be looking up at the pressure reg and have to remove a couple of pipes from it to get to the FDV anyway. So you will soon see the 12mm headed bolt. It has a few names, one of them starts with B and shouldn't be said in polite company.

I would expect, having never had a good look at a 2.1 TD engine bay that it would be a little easier to get the FDV in and out there. Now if it was a 2.5td

[jorgy9]

Advice: since u'r going to replace the FDV and will -hopefully!- have one in hand, go and take the plunge of refurbishing it. There's the necessary kit from Citroen (No.95 669 034) including a few o-ring etc -cost must be a few ££-. It'll be a shame once u do that effort to put in a piece of kit that could be even worse than the one it replaces (unless u sure it's in a better state!) . Plus, you'll get the joy a properly working FDV = all hydraulics better. Can't your indy help you if you're worried about tackling it yourself -I think the only critical part is readjusting the pressure on it when you've put it back o nthe car, and it needs a pressure gauge for doing this-.

regards
George

[kiwi]

Cheers, Agreed. My plan is to swap them over and then refurbish one as time permits. I'm assuming that they are the same across all the models? The 2.0 sei and V6 are both Mk1s whereas the 2.1TD is a Mk2. If and when I ever get my 2.1TD back it would be nice to have a good one to put on it.

Regards,
Kiwi

[jorgy9]

I'm not sure about S1 and S2, there might be a difference because S2s got the 6+2 pump and I don't know what implications that had on the use of a FDV -did they still use it for steering/brakes pressure distribution?-.

The FDV appears to be identical for all engines, only that automatics also get an additional support bracket on that.

Also note that the FDV has 2 little filters (No.95 534 068) that will need cleaning/replacement when u refurbish.

regards
George

[Assich]

The 6+2 pump doesn't need a FDV. It has two outlet pipes, one feeding the steering and other feeding the suspension and brakes. Not all S2's have this pump though.

As for depressurising the system - my first car had a badly leaking valve on the pressure regulator so I welded it up and just set the suspension to low and undid a pipe coneection a little to depressurise the system. Works fine and no fiddling about in lack of space with the regulator valve. The only thing I can think of that benefits from using the regulator valve is bleeding the pump. I do the same now with my latest S2 and particularly with anti sink on the back end to depressurise the rear.

[kiwi]

Forgive me if this is a silly question but does it matter what position the ride height lever is in when starting the car?

Regards
Kiwi

[jorgy9]

No, why?

George

[kiwi]

I think I read something somewhere about strut damage during starting if the lever was in a certain position and the suspension was in hard mode. Might be the Pinot I've been drinking lately is getting to me......

[Miguel]

By the description, I have the same problem, a leakage in the flow distribution valve.
Is this a common problem?
Did you refurbish it already?
Was it easy?
If anyone knows a link to a description of the procedures, please tell-me.

[Miguel]

P.S.

Is this description correct?
http://www.calumscott.me.uk/cars/xm/proble...chapter=fdv_rep

I forgot to mention that when the pump is hissing (injecting the system, but not in a continuous way) I feel small movements in the steering wheel. Is this an indication of a starting to fail valve?

I’m for Portugal and I can’t find any xm in a scrap yard, (even on the road it’s rare to see one), so, if I have to change, I’will probably bye a new one, do you have an idea of how much will cost?

Cheers.