Catastrophic hydrolic failure. Low height, no brakes &no

[jthomsit]

Hi all,

A plea to the infinite wisdom of the members here... I've been reading posts for a couple of days now and am fairly sure the response is going to be to first try - drain, flush and refill but before I embark on this I thought to seek a second opinion as I've never worked on hydropneumatic suspension before.

My Car
I've had my BX for a year, done very few miles but never the less my regular drive. No major problems (more later) with the hyrodlics ever and handling was great. It's a 16v gti 1990.

Potential Warning
I confess I've been stupid! When I was driving too enthusiastically, occassionally the STOP light would biefly light (along with the hydrolic light) but would go off almost instantainiously. I just assumed it was sloshing around and getting low... I never checked the level. No funny noises. The PAS would go hard every nown and again but again it was intermittant and never caused me problems (the STOP light did not light when the steering went heavy)

The Trigger
So... I, showing off to a friend, but the car on it's maximum height, no problems... Then put it on it's lowest height. I hadn't noticed because I had been out of the car but the STOP light and hydrolic light lit.

The Symptom
It now won't go back up to the normal setting, there's no PAS and no brakes. There's no clicking. I've tried moving the lever. There is green fluid in the resevoir but can't get a proper reading as it's on lowest setting (the indicator is above max). On the clear pipe from the front into the reservoir, I noticed a yellowish (they're yellow pipes) liquid very slowly moving up (as there was an air bubble at about 5mm per sec) . I didn't notice it clicking at all.

Oh nutz, it was such a fun car....

I've read lots about the front getting stuck or the back, but haven't seen any posts of catastophic failures (probably searching for the wrong term or expression).

Any help would be greatly appreciated.

Thanks.

[Dollywobbler]

If the pump is not doing its usual clatter to pump the car up, it's a likely candidate. Check the belt and tension. Or it could be that there's a really bad leak somewhere and it's now got far too low. On personal experience, that's unlikely if you'd just checked the level on max height though.

[ken newbold]

by running your car on high setting with low fluid, you've probably drawn air into the system.

Firstly check your LHM pump belt is on and tight. If it is, you might be lucky and get the pump to start pumping by simply turning the steering slightly left to right, sometimes it works.
If not you'll need to prime to pump manually.

Follow the thick black hose back from the pump to the reservoir, undo it from the reservoir end and fill the pipe with clean LHM. Then refit it quickly and try again.

It's probably best to have the 12mm pressure release screw undone for this but I'm not sure how easy that is to get to on a 16v car.

[jthomsit]

Thanks both of you for your fast, helpful replies.

I didn't get round to checking the level before it broke. I was just saying the the indicator is reading over the max with the car on the ground (so not the proper reading).

I pulled off the pipe you mentioned (the HP pump supply) earlier today and there was green fluid in it. As you suggested the bleed screw is quite difficult to get to with the 16v skirt and being so low, but I will give it a go, check the tension and to work the steering wheel tomorrow (hoping snow holds off).

I'll post my results and thanks for the help.

[Kitch]

I'd run it up, check the belt isn't slipping and drop another litre of LHM into the res (if it overfills it'll spill out at worst...put something down underneath. You can always get the level right later when it's up again)

Then as Ken says, undo the 12mm bleed screw no more than half a turn (should hear some faint hissing). Fast idle the car and move the lever to the top, then turn the steering full lock each way and hold it for a few seconds each way. Stand on the brakes a few times too.
The STOP light often comes on while going into top mode, but should go out again after 5secs or so on a strong system.

The other thing to note is the lever....is it giving any more/less resistance than usual? Just wondering if a linkage or height corrector is stuck, but that would usually result in one end rising and failing on it's own.

I've only ever had a car fail to rise because the fluid got low, or because I'd taken the pump hose off and failed to bleed it properly.

I'd doubt it's anything major. Major failures usually involve big puddles of green fluid on your rented house's driveway.

[Vanny]

It might help if you provided a location, then you might get a learned volunteer to come and cast an eye over the problem?

[jonathan_dyane]

I agree it is most likely that you have air-locked it through putting it on high with insufficient LHM.

If you can't get it to rise using the bleed screw, retighten it, and see if you have any power steering. If you have, hold it against full lock and you will find it should then rise as the LHM is made to return from the power steering circuit to the regulator.

[citronut]

i would have thought if it were an air lock, sink her right down then back up to highest setting a few time shoukld sort that out,

at a citroen service agents i used top work for back in the days oF the DS,CX DERSH and G's,

citroen used to state after openning a hydraulic system for repaire purposes, to leave the engine running for two minuites with the bleed valve open, then raise the revs to 2,500 whilst clloseing the bleed valve,

regards malcolm

[thorter]

Check that the tank to pump inlet hose does not have a split in it somewhere. This can be quite hard to spot, but draws air even if the hose is full of LHM.

Fred

[jthomsit]

You've all been a great help.

The bleed screw was beeing very tricky with all the 16v trim and my trolly jack was too big to go under as well.

I did what you suggested, topped up, checked the supply hose and worked the steering wheel. The light was on still and there was a slight knocking noise (could it have been an HP pump with not enough fluid in it) when the steering wheel was held on full lock. With the PAS still not operational, I built up a sweat working it from side to side and felt the slightest glimmer of power assistance. Kept this up on full lock for about 5 seconds at a time (the knocking noise was scaring me a little). After a while I felt the car rise a little, so I kept at it and got it up a little more, enough for me to get under the car with a set of axel stands and bleed the valve!

Worked a treat! Brakes, PAS and uppy downy all working at the lights not even on!

It's a credit to you all, your knowledge and experience. Thanks.

BTW I'm in london and my baby is actually for sale. So you guys have saved me from forking out or cancelling the auction. It's already been spotted on the 'spottings' section, where it's been riddiculed for being pink and not having the propper wheels but it's my baby never-the-less it's listed on eBay if any one is interested- http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... :MESELX:IT

Thanks all - any local's are welcome to come see it, and guess I should offer a pint as well

[Vanny]

pressure release screw on a 16v is no harder to get at than any other model, so long as you have the correct tool.

I can not stress just how important flexi head ratchet spanners are in saving sanity/marriages!

[Linegeist]

I can not stress just how important flexi head ratchet spanners are in saving sanity/marriages!

Gosh! That sounds a bit pervy to me. I'll stick with the morning tea taken to herself in bed and the obseqious bowing and scraping that's got me this far.

Are them flexi wossnames battery or mains then?

[Aerodynamica]

pressure release screw on a 16v is no harder to get at than any other model, so long as you have the correct tool.

I can not stress just how important flexi head ratchet spanners are in saving sanity/marriages!

So long as the radiator is not too hot, you can reach this from the LH side behind the radiator!!