Xantia accumulator sphere..Life expectancy!

steviewonder7 · Unread post by **steviewonder7** » 06 Dec 2005, 16:10

Hi Folks,

Just a small query,how long would you expect a recon accumulator sphere
to last.I say this because i fitted one from pelaides approxiamately 7 months
ago after noticing the pressure regulator clicking like it does a bit too often
considering the time interval allowed for said clicking.Now I've noticed the regulator up to its old tricks again,plus the Xant's rear end raises itself when I come to a stop at traffic lights etc etc.
Any ideas folks,does it sound like a new sphere is in order????

Thanks in advance to your replies.
Steve

mezuk04 · Unread post by **mezuk04** » 06 Dec 2005, 16:27

From what ive learnt off here it should certainly last much longer than 7 months! much much longer

steviewonder7 · Unread post by **steviewonder7** » 06 Dec 2005, 16:39

Could there be an underlying problem,perhaps causing the regulator to work harder than it should.When I fitted the existing accumulator I fitted the 'O'ring as your supposed to therefore(hopefully) ensuring no leaks were going to happen.?

Steve

Unread post by **Peter.N.** » 06 Dec 2005, 17:20

Their life can be very variable. I have had them last for several years but also fail in less than one, and these have been new ones from GSF. They do have to work harder than most of the rest as the pressure is constantly varying, they also of course run at full pressure, but I wouldn't have thought that should drastically shorten their life.

mezuk04 · Unread post by **mezuk04** » 06 Dec 2005, 19:52

surely it comes with some sort of 1years warranty like any other thing out there?

Mandrake · Unread post by **Mandrake** » 06 Dec 2005, 19:58

I think the main reason accumulators don't last as well as the suspension spheres is the pressure - they have the full 170 bars on them any time the car is running, and that causes the diaphram to fold back on itself a lot as the sphere is 3/4 full of oil at that pressure despite 62 bars of gas pressure.

This puts strain on the diaphram, and as gas pressure is lost the diaphram is folded back on itself even more and it doesn't take much pressure loss to overstress the diaphram and cause it to fail. By the time it gets down to half normal pressure I would say the damage is already done and the diaphram is fatigued.

Having said that I would be disapointed if one lasted less than two years.... 7 month is definately premature.

I replaced my accumulator with a new "genuine" one when I got my car about 5 months ago, and when I recently did a pressure test on it a couple of weeks ago I found to my surprise that it was still EXACTLY at 62 bars, so I expect it to last a couple of years at least based on that...

Also the accumulator can't have any affect on the cars tendency to "rise" at the back when you stop at traffic lights... that is simply the suspension at the back coming to rest at an incorrect height due to dynamic movements while driving and then being clamped at that height by the rear brakes. Try using the hand brake at traffic lights instead of the foot brake. (Or easing off the brakes as you come to a stop)

Regards,
Simon

mezuk04 · Unread post by **mezuk04** » 06 Dec 2005, 22:12

I would enquire as to the warranty as obviously by the posts it would seem 7 months is just premature

by far.

I would see about getting a replacement one, for free of course!

AndersDK · Unread post by **AndersDK** » 06 Dec 2005, 23:56

There are other possible reasons to fast ticking pressure regulators than a flat acc sphere.
But a flat acc sphere is by far the most common reason. And by far the cheapest and easiest first option.

The PR itself may leak in the feed valve to the acc sphere.
The brake doseur valve may leak.
One of the suspension cylinders may leak.
One of the HC's may leak.

These are all internal systems leaks which can not be seen as green puddles under the car. Instead you will have to diagnose the leak-back flow in the small rubber return lines at the reservoir to find the problem.

For the DIY mechanic the biggest problems are always lack of special equipment and spare parts for immediate swapping.

First try would be any other proven sphere to go as acc sphere. This could well be one the front suspension spheres for testing. Simply swap one of these with the acc sphere and then test the tick interval again. But NEVER drive the car with an acc sphere in the suspension. You have been warned

Next test is looking for flow from the SMALL rubber lines at reservoir. Ideally there should be none. (engine running idle). Depending on wear & tear there will be some slow dripping. But a running flow is a NO-GO.
If good acc sphere, no flow and still fast ticking it can only be the PR itself leaking.

Mandrake · Unread post by **Mandrake** » 07 Dec 2005, 07:28

AndersDK wrote:There are other possible reasons to fast ticking pressure regulators than a flat acc sphere.
But a flat acc sphere is by far the most common reason. And by far the cheapest and easiest first option.

The PR itself may leak in the feed valve to the acc sphere.
The brake doseur valve may leak.
One of the suspension cylinders may leak.
One of the HC's may leak.

Anders, add to this list the hydractive control blocks, as these seem to be a BIG source of pressure leakage in some cars, far exceeding any of the other sources you mentioned.

I didnt mention it until now because the OP's car isn't a Hydractive 2, but it bears mentioning for anyone else following the thread.

On my car with a perfectly normal accumulator that tests 62 bars, the regulator is currently cycling every 18 seconds, but if I disconnect/disable the hydractive valves by unplugging them or removing the hydractive computer fuse, the regulator cycle time increases to 3 minutes 45 seconds.

Listening next to the valve with the engine off but the valve activated there is audible hissing indicating leakage.

I've had confirmation from at least one other person that their car does the same thing, so I don't think its an isolated case. I'll be taking one of the valves apart soon anyway to tweak the damper valves so I'll see if I can find what the source of leakage is. My guess is either particulate grit stuck in the seat of the needle valve, or a failed o-ring.

So in summary, anyone doing the regulator cycle time test for an accumulator on a Hydractive (2) car ought to disable the solenoids during the test or you might get a false "fail" of the accumulator.

Regards,
Simon

Rostami · Unread post by **Rostami** » 07 Dec 2005, 09:38

Simon,
I have been reading you threads about the leak...can you please tell me where the solenoids are located on the HA2 Xantia? Can you access the front ones from the engine bay?

I would like to do the same experience as I have a similar problem!

Thanks,
Rostami.

Mandrake · Unread post by **Mandrake** » 07 Dec 2005, 09:54

Rostami wrote:Simon,
I have been reading you threads about the leak...can you please tell me where the solenoids are located on the HA2 Xantia? Can you access the front ones from the engine bay?

I would like to do the same experience as I have a similar problem!

Thanks,
Rostami.

Hi Rostami,

The front solenoid is fairly easy to reach under the bonnet (at least on a 2 litre petrol, some models like the TD's have a lot of stuff in the way) it's the cable and plug plugging in on the left hand side (looking into the engine bay) of the block the hydractive centre sphere is screwed onto at the bottom of the radiator.

Due to the way the computer works, unplugging the front solenoid will also disable the rear solenoid, so there is no need to unplug that seperately.

However if you're refering to your Activa, there is a third solenoid (at the back of the car) which controls the rollbar stiffness, and I don't know if this will also deactivate, so your best bet is to simply pull the hydractive computer fuse out from the fuse box during the test. (Easy to tell you've found the right one - your suspension will become quite stiff

)

Regards,
Simon

steviewonder7 · Unread post by **steviewonder7** » 08 Dec 2005, 17:21

Thanks for your replies chaps,I shall swap the accumulator sphere over for a new supension sphere like Anders said and see if there any noticable difference.I shall have to have look for any weeping joints and dribbles from the return lines at the reservoir.