The Xantia had a weird turn today. The rides always been very hit and miss, needs new rear spheres soon and i think we have some air getting in.
however it has never sunk as much as it did today. usually theres a few cm, maybe up to an inch of sink if its been sat for a good few days, but today it went from ride height to 2 finger front 0 finger rear in about an hour, after a quick drive.
Theres no obvious leaks I can see. Could this just be the rear spheres finally giving up? stop light was on for about 4 seconds on ignition, almost like it had been sat for longer, and it came up at the usual speed. Ride was the usual afterwards
Stu
Cars
1995 Xantia 1.9TD SX in (faded) Red
2003 Fiesta 1.4 Zetec in GREEEEEEEN 2001 206 1.9 LX
2001 Saxo VTR
1999 Saxo 1.1 East coast
1999 Punto
1996 306 1.8 XN Auto
1996 Fiesta 1.3
In my experience they all have a mind of their own, some sink sometimes and not others, some don't sink at all. Depends on the general condition of the hydraulics, often the height control valves become leaky internally. If it drives OK don't worry about it or you could end up spending a lot of money for no real gain.
I've found ruptured rear sphers to be certianly one casue of sinking...
If they are near the end anyway it'll be a good idea to swap them to exclude them if nothing else..
Although the rear anti-sink is mis-names, it certainly can have an effect as it has an (albeit minor) role in ensuring the anti-sink valves close promptly.
It's main function is as a reatr brake accumulator whent he anti-sink valve is closed.
The anti-sink valves themselves hardly ever fail...
The Green Lady's suspension had been behaving increasingly oddly for months. Porpoising front, STOP taking a long time to go out; first trip of the day, the rear would sink after the stop light went out and then take 15-20 seconds to rise back up.
Changed all 6 spheres, cleaned filters, drained and bled the hydraulic system - symptoms all gone. This morning, after being parked all week-end, I remembered to count the seconds for STOP to go out - 6.
Correct me if my logic is wrong, but because it's a local accumulator, doesn't the A/S sphere reduce the time the rear suspension takes to rise because it, rather than the more remote Accumulator, can supply a significant volume of LHM under pressure?
2012 Subaru Forester - capable but no magic carpet
2011 Grand C4 Picasso VTR+ 1.6HDi - not missed!
1995 Xantia Estate SX 1.9TD in Vert Vega "The Green Lady" - sadly missed
1998 Xantia 2.1 VXD Estate in Mauritius Blue - R.I.P. (terminal tin-worm)
Also, should have said that a duff main accumulator can cause sinks too due to again there being a lack of main-line pressure available to rapidly and positively close the anti-sink valve...
