xantia activa hydraulics

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stephen burch
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xantia activa hydraulics

Post by stephen burch »

I have a 1997 Xantia 2.0 8 valve with hydractive suspension and have a problem with the stop lights taking excessively long to go out.I have changed the accumulator sphere, hydraflushed the system and cleaned the filters and tank internals thoroughly before refilling with LHM.I feel I can discount the hydraulic pump as being worn as after I have done this procedure the stop light goes out in around 20 seconds. However, if the car is used for approximately 100 miles the stop light takes approximately 45 seconds to go out. The more the miles the longer it stays on. I also have a problem with the rear of the car jerking up when it is building up pressure, although this doesn't happen when the system is cleaned, only about 150 miles later, so I feel this would eliminate the anti-sink valve. The rear arm bearings have also been replaced so there would be no binding on these . The cleaning procedure has been done twice now and with the same results.Any thoughts anyone?
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AndersDK
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Post by AndersDK »

Hmmm...
Stephen - you don't leave us much guesswork [8D]
You have done all the basics, ruling out the common problems [;)]
I believe the 2 symptoms are linked, as the rear shoot may well be caused by a strange pressure problem, indicated by the warning lamp.
My guess is, that the rear may shoot up, once the lamp extinguish, as this exactly indicates the safety valve opens for suspension feed pressure.
The lamp indicates you have a pressure loss problem, which also means the PR should never tick at all.
You're defo the pressure release screw is closed on the PR ?
Also you've not lost the ballbearing under this screw ?
The pump is not likely to take in air, as then also the servosteering port of the pump would be weak.
I'd say you should start looking for HI return flow in the reservoir return hoses, indicating a pressure eater somewhere.
Start with the brake doseur valve return.
BTW : defo a new accumulator sphere (on engine block) ? no recon or s/h unit ?
stephen burch
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Post by stephen burch »

Thanks for the reply. The ball bearing is intact and the PR screw is tight. The sphere is brand new and purchased from Andyspares, not S/H or recon. I have not noticed any leaks.
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AndersDK
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Post by AndersDK »

Eehhrr... Stephen -
By leaks I mean INTERNAL leaks in the system components, by way of the return hoses ??
Am I right assuming you have no ticking sound from the PR ?
BTW : How does your Xantia reacts to the Citaerobics ?
stephen burch
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Post by stephen burch »

Hi Anders.
I have checked the latest time from starting the car to the stop light going out and it's up to 62 seconds. The accumulator is ticking once every 7 seconds when full pressure has been built up but doesn't seem to tick until the stop light goes out. Regarding the aerobics, it completes every stage but takes longer than it should.
philhoward

Post by philhoward »

7 seconds is WAY too often; the pump wont last long at that rate! As Anders says, it's look for something with a big internal leakage, by the sounds of it. The brake valve is usually the favourite culprit. Check which of the hoses on the top of the LHM tank are the returns and try them one by one until you find the one which has a flood coming out of it.
It's definately not the accumulator sphere, if it takes that long to build up pressure; a duff accumulator needs next to no time to extinguish the STOP light.
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