ZD8I ("ZD8I" <u40580@[EMAIL PROTECTED]
>) gurgled happily, sounding much like they were
saying:
> Firstly for a very long time, the rear-end has sunk overnight which I
> now believe from reading other posts is a faulty anti-sink sphere. A
> relative who had a BX advised that this was a common Citroen fault and
> we lived with the minor inconvenience.
Yes, together with a worn brake valve (think master cylinder) allowing
the rear suspension pressure to leak back more easily. The rear brakes
take their pressure feed from the rear suspension, to ensure that the
braking effort is load-related.
It's merely a minor inconvenience and causes a small extra delay in
rising. Nothing serious.
> Then around 1,200 miles ago after not being used for a year (the car was
> in storage while we were out of the country) a fault appeared where the
> rear suspension would only lift from its sunken position if the engine
> was run at fast idle for 15 seconds or so. If the car had been stopped
> for a period and not sunk, as soon as the engine was started, the rear
> end sunk immediately and required the 15 seconds of fast idle to regain
> its composure.
Partially down to the problem above, because the system's losing pressure
more quickly than it should, but it's not helped by a flat ac***ulator
sphere. Think of the pump as the alternator and the ac***ulator as the
battery. The ac***ulator stores pressure, which is then released through
the system. If there's no store left, the pressure can't be supplied as
quickly - hence the slow pump-up.
When the engine's idling and the car's at normal height, how long is the
cycle time? You should hear a psshhht-click-<pause>-pssshhht-<click>. The
duration between clicks should be a minute or so, but can be almost
nothing. The psssht is the pump working to recharge the ac***ulator.
If you've got a flat ac***ulator, and the engine cuts whilst you're
moving, you will have NO BRAKES in very short order.
> Until the suspension reaches its full height, the brakes barely work at
> all.
Ummm, you don't drive off until it's fully up.
> When at normal height, the suspension is comfortable and the brakes are
> excellent although I have never really liked the on/off nature of the
> brakes, the lack of feel through the pedal and ease at which the ABS
> modulator cuts in. Is this another fault?
No. That's down to the fact that your foot isn't creating pressure, like
a normal master cylinder, but opening a valve to release stored pressure
into the system. Expect the pedal to be have in the same way as a normal
one, and you can over-brake very easily. It's not as "bad" in Xants as
earlier hydraulic Cits, because there's a spring in the pedal linkage to
give some artificial pedal travel - but some people never do get used to
it. By the sound of your comment about "on/off nature", you may be one.
The other possible cause is that the brakes need bleeding. That's quite
likely if the ac***ulator sphere's totally flat, as the little gas left
in it will have been released into the system when the diaphragm
punctured. Whilst the suspension and steering are self-bleeding, the
brakes are a "dead end", so need to be done as on a normal car. Rather
than give a spongy feel, air in the lines on a hydraulic Cit leads to a
delay when you start to brake - during which time, you naturally brake
harder. As a result, when they do kick in after a few moments, they do so
too hard.
> We believe all spheres are original so would it be sensible to replace
> all six of them together and is this likely to fix all three faults?
ORIGINAL? After 12 years? They're meant to be replaced roughly every
three years or so... Definitely get 'em all changed. Being an SX, you've
only got the six - the anti-sink's a bit of a bugger to get at, but the
rest are easy. Definitely change the fluid, too. If the fluid's never
been done either, it'll be filthy - change it for flu****ng fluid -
available from GSF etc. After a thousand miles or so, change it for clean
LHM. The actual fluid change is dead easy - don't forget to bleed the
brakes through fully to get all the old out and the new in.
If you think the suspension's comfortable now, wait until you try it in
full health. I'd be amazed if you don't have several completely flat
wheel spheres, leading to no suspension travel on those wheels.
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