Help! Sphere union

lexi · Post by **lexi** » 10 Feb 2010, 22:39

Pop me you address Toby in Pm. I will send you a seal for the main union on Pump. I have one here for Jim as well for a spare. They are available from Stealers in packs of 5 and part no is 4026.88.

Toby_HDi · Post by **Toby_HDi** » 11 Feb 2010, 12:49

Well I've sorted the leak from the sphere. Popped it off and the seal looked fine so refitted it carefully and I can't see it leaking.

A thorough bout of Citaerobics to make sure all works has uncovered that the back sometimes does not want to rise. I'm putting this down to air as on moving the lever you can hear it. Almost like the noises from a radiator with air. This air must either be from the dodgy union (not that it drew any WD40 when I checked) or from the flat Activa accumulator which I believe to be ruptured. Either way I can't force it out and I suspect the fact I'm stuck in firm mode isn't helping.

Really then I need to replace the Activa accumulator and the pipe into it for piece of mind then sort out the ECU. Hydraflush and a brake bleed can wait until that is done.

Post by **CitroJim** » 11 Feb 2010, 16:43

Hi Toby,

That's good that the centre sphere is no longer leaking. If the Activa accumulator sphere joint is not leaking, it'll be OK. There's a lot of pressure there and it'll never suck air in but if imperfect it'll leak like fury...

It does sound like air in the system and a bleed of the rear brakes at least will be essential to clear it. You may have a lot of nitrogen from a ruptured sphere membrane adding to the problem. A likely candidate is the anti-sink sphere at the rear. Did Richard check it?

Another cause of air noises (sounding like a flushing toilet) can be caused by a leaky rear hydractive electrovalve. Have you still got the fuse pulled?

The noise is caused by LHM rushing along the leakage return piping.

Have you replaced your main accumulator and if so, what's the new tick rate?

Leaky hydractive electrovalves can be checked by slipping off the leakage return pipe, blocking it and attaching a length of clear hose to the electrovalve spigot and directing the other end into a jamjar. In hard mode, with the hydractive ECU fuse removed, there should be almost zero leakage. In fact it should only ever spurt on the transition from hard to soft mode.

DickieG · Post by **DickieG** » 11 Feb 2010, 18:54

CitroJim wrote: A likely candidate is the anti-sink sphere at the rear. Did Richard check it?

No I didn't on the basis that as all of the other centre sphere's were flat or very close to flat.

Post by **CitroJim** » 11 Feb 2010, 19:30

Thanks Richard

We can assume then the A-S sphere is duff then...

I'm pretty sure if it is flat or leaky, it'll have some effect on speed to rise at the rear due to where it is in the hydraulic circuit.

Toby, it's just the same job as swapping an Activa Accumulator only access is poorer...

Xaccers · Post by **Xaccers** » 11 Feb 2010, 20:16

Loop a 9mm flare spanner onto the pipe nut through the underneath of the bracket that the AS sphere screws into.
Then unscrew the AS sphere.
The bracket will hold the spanner in place and by unscrewing the sphere you'll be unscrewing the pipe nut too.

When you fit the new sphere, use a new seal on the pipe, fit the sphere just enough to hold it to the bracket, then screw the nut into the sphere slightly.
Re-attach the flare spanner, screw the sphere home and it will screw the nut in too.
Nip the nut up and job done.
Oh and use the large o-ring that came with the sphere as you would with the others (ie fit it to the sphere), even though it isn't needed.
It keeps the sphere from rusting to the bracket

Toby_HDi · Post by **Toby_HDi** » 11 Feb 2010, 21:04

I've replaced the AS sphere. As we assumed it was duff, iit was probably flat but it wasn't ruptured as far as I could tell.

The Hydractive fuse is still pulled, the only leak was from the sphere but that seems to have been rectified.

Xac, thats a good point about rusting to the bracket. I believe this is what has happened to my Activa accumulator. It just will not budge and I do have a fresh one waiting to go on.

The accumulator is new. New tick rate is much improved over the old one though I haven't sat and listened to what the new one actually is. The car no longer sinks at the rear after being switched off.

I'm assuming the air is the cause of the rear not rising sometimes.

Thanks for helping. I think I'll swap for Hydraflush then and bleed the brakes, hopefully that'll sort the problem. Then just the Activa accumulator and ECU to do.