There is a one way valve between the pressure output of the regulator and the rest of the hydraulic system preventing back feeding into the pressure regulator - to be honest I don't know where it is in a Xantia, probably in one of the pressure distribution blocks on the firewall bulkhead, perhaps someone else knows.charentejohn wrote:Thanks, you have answered my questions, even the ones I hadn't asked yet. I was dreading having to lower the car as it would have meant starting the engine so more LHM everywhere. I assume the regulator is one way so holds the pressure in the system so the inlet is now depressurised anyway, it must be as fluid has stopped spraying out..........
Also as soon as you depressurise the pressure regulator with the bleed screw the anti-sink valves will act to isolate the suspension making back feeding from the suspension impossible even if there weren't a one way valve, so you're quite safe to remove the accumulator sphere and the leaking pipe once you've opened the bleed screw a half turn, whether or not the suspension is still up.
Sorry I hadn't noticed you were in France, I assumed you were in the UK.I can buy a pipe here but often you have a wait while they order one, can be days or weeks, but I can live without the car for a week or so. I will make sure I get the right pipe seals as well, normally all in a packet but not guaranteed to be.
I will remove the existing pipe to check which seals it has. I can buy one here for 32 euros inc postage so if a local parts place can match this I will buy there as I will be able to see it before paying.
Have a look a bit further down the third V6 thread I posted a link to and you'll see a photo from CitroJim showing the difference between the two types of seals - one has the rubber seals, one has the metal disc, and the end of the pipes are slightly different. That should help you to identify which one you have when you remove the pipe.
If the car is 1994 onwards (has anti-sink) it will have either 8 spheres if its Hydractive 2 or 6 spheres if its not Hydractive 2.I will also change the sphere, as fluid everywhere daft not to. Still trying to find the bills I got with the car as spheres were changed but I can't remember how many, 4 or 5 ?
To change the accumulator sphere you only need to open the bleed screw a half turn, no need to depressurise the entire suspension - same for replacing the pipe between the pump and the regulator.So more questions - I assume I will need to depressurise before changing the front sphere ? so fit new pipework, lower the car, depressurise and change sphere.
It's not advisable to run the engine with no oil in the hydraulic system and the pump unprimed. Xantia hydraulic pumps don't use ball bearings instead using bronze bushes that are lubricated directly by the oil going through the pump, if you run it completely dry the pump is running without lubrication of the bearings. It might be ok for a couple of minutes but any length of time running dry is likely to damage the bearings or at least wear them.Also as I have lost a lot of fluid I may as well do a fluid change SInce I am half way thwere already ? Should be ok to run the engine on low LHM just to lower the car ? I assume these hydraulis are like my mini digger, low fluid does no damage as such just that stuff stops working until topped up.
If there was not enough oil and the pump was running dry you would not be able to lower the suspension anyway, the pressure regulator has to be running at normal pressure or the anti-sink valves will close locking the suspension at the height its already at.
As I said earlier though, no need to lower the suspension to replace that pipe or the accumulator sphere. Any other spheres on the car, yes.
Nope, that's perfectly normal behaviour.Just out of interest, for a few months now I noticed the car would sink 2cm or so at the front when parked for 10+ minutes, never went any lower if left for days but did drop quickly at first. Once started rose back to normal straight away. Is this a symptom of the above, dodgy sphere, slight fluid leak ?
For the first 5-30 minutes or so after turning the engine off the suspension will sink slightly due to normal leakage in the height correctors. After that the anti-sink valves will close and that source of leakage is isolated. The car will then stay at that slightly lower hight anywhere between hours and days, typically many days. Nothing to worry about.