Weird loss of front suspension pressure ....

[Linegeist]

Had a weep on one of the returns today behind the NSF wheel, dribbling LHM onto the drive. Simple perished pipe, so I jacked the car up for access, whipped off the NS front wheel and cut the split 2cm length of rubber pipe off. As the rest of the pipe was OK, I pushed it back onto its spigot and retightened the clamp.

However, when I lowered the car on the jack, and started the engine to get the jack out from under, the front suspension refused to budge. Rear was fine, lots of hissing 'n stuff, but no front suspension - which stayed resolutely on its bump stops. Tried all the citaerobic tricks, plus setting the height lever to MAX with the footbrake depressed - nothing.

I eventually got the car off the jack by messing about with wooden blocks under the front NS tyre and then driving carefully off them - and then tried driving the car slowly down the village road to see if the joucing would free something up. As soon as the car hit the first bump, the front suspension decided to play ball and did a Lazarus trick, rising to its normal height and going all nice and squishy again.

Can someone possibly please explain to ol' thicko here, what exactly was going on .... or should I confine myself to waving garlic at the car and chanting?

[Way2go]

It sounds as if you have a sticky linkage on the height corrector EXCEPT that if you were selecting intermediate or high this should overide the linkage anyway. So if it wasn't responding to the lever in any position, then probably gunge in the height corrector (or FDV?) was blocking the high pressure flow?

[mat_fenwick]

should I confine myself to waving garlic at the car and chanting?

I wouldn't do that Bob, the neighbours might think you're mad!

Oh, wait.....

[jonathan_dyane]

Every hydropneumatic Citroen I have ever worked on (GS/GSA/CX/BX/XM) has exhibited this tendency, where if you jack them up with a block of wood on the jack on lowering the car the jack becomes trapped and the suspension refuses to rise, regardless of whether the height control lever is manipulated. My solution like yours is to drop the car onto blocks of wood beneath the wheels in question, however as soon as the jack has been removed the car has then risen. Why your car did not do this I don't know, but would suspect checking for sticky height corrector mechanism.

[Linegeist]

My solution like yours is to drop the car onto blocks of wood beneath the wheels in question, however as soon as the jack has been removed the car has then risen. Why your car did not do this I don't know.

I reckon I might Jon' - ruddy cheap supermarket garlic.

should I confine myself to waving garlic at the car and chanting?

I wouldn't do that Bob, the neighbours might think you're mad!

Oh, wait.....

I'll have you know sir, I strongly resemble that remark!!! <burble, wibble, drool>

[kiwi]

Sounds like that typical one off event that we owners of a BX are sometimes afflicted to

Does the car still exhibit any problems now though? If not then no problemo

Maybe there was an air bubble working though your pipes?

Interesting enough I have noticed with my own BXs a tenadancy for them to be a bit slow on the rise when they are not used much or just used on short journeys. I guess putting them through a 40+ km workout at least 3 times a week on twisty undulating roads tends to help lubricate the joints

Probably helps to dislodge some sludge of even air bubbles that may work into the system?

[Simon B]

Sounds like that typical one off event that we owners of a BX are sometimes afflicted to

We have probably all got stories. 20 years ago, I remember my BX14 sinking on the bump stops after loading up for a holiday, and the NS front deciding not to come up afterwards. Drove off the drive at a precarious angle, thinking that the holiday was off, and after a few yards it shot up, and never did it again.

[MULLEY]

Time to try hydraflush

[Defender110]

Would it not be more likely be sticking/locking struts rather than hydraulic delivery especialy as like in Simons case where it was just on one side?

[MULLEY]

Possibly a weak hydraulic pump, coupled with old age/wear & tear in the rest of the system & slightly sticky struts could be the cause. Hydraflush would be the cheapest way of seeing if that fixes the problem & at the very worst, it'll clean out all the crap regardless.

[Linegeist]

Ah! Hydraflush - the Pachyderm in the Parlour.

I know I need to do it - but I'm worried about introducing a whole slew of new problems.

It's a 'new' pump from Pleiades - jolly effective too - and the car's in pretty good nick. I don't think the struts are sticky - although I did the Citaerobic strut-flush-through thing via the leak-back plumbing when I got the car last year. The front suspension's really nice, floaty and soft - when it pumps up.

Two questions then:

1. How often does a Hydraflush (sounds remarkably like a bog-clearing exercise doesn't it?) introduce fresh faults - ie by dislodging particles/opening up clearances?

2. Who's the best supplier to get the flush from? I can't get it locally - there IS nowhere local to where I live!!

3. How much do I need?

Sorry. I know that was three questions. I got confused because I was in the middle of the morning's BX garlic-waving and chanting rituals while typing this ............

[kiwi]

With regards to Hydraflush, I have only used it once and to be honest I could not see much of a differance. For one you have a lot of dead ends on the Hydraulic circuit and the only way to ensure they are clean is to flush them by bleeding with clean LHM.

Hydraflush is not a quick fix, it has to stay in the system for a few thousand miles to clean through. Either way your still going to find the best cure is bleeding the dead ends of the system before and after. That gung it dislodges has to go somewhere most goes back to the Reservoir the rest finds those ends.

[MULLEY]

I wouldn't say that it may cause further problems as all it's designed to do is continue to lubricate (probably not quite as effective-hence its recommended to remove it) & capture the dirt thats present in the system. Most of it should end back in the main tank, however, what i also did was fit a small fuel type filter as an add on to the main lhm tank, the (pipe) one where when you press the brake pedal it squidges lhm back into the tank. That way i felt that i was capturing more crap to lesten the circulation of the hydraflush with the muck in it. I then emptied out the hydraflush after a few thousand miles of driving, re-filtered it to remove the crap, & then put it back in again to continue the good work that i'd noticed, i also changed the little fuel filter as well as that was full of crud. Then after a few more thousand miles i then exchanged if for nice clean lhm, with another replacement fuel filter, i just keep it on all the time to continue to grab any muck present in the system as it's nigh on impossible to remove all 100% of it.

Kiwi's got a point about the dead ends, i'd do those as a matter of course, especially if youre going to try hydraflush anyway, if you look on the diy section it does cover this aspect anyway.

I personally think hydraflush should be part of a service schedule every few years.

I got it from GSF, it only comes in 5 litres, so that's all you need, unless you've got leaks, in which case you'd better buy 2 lots.

Hope that helps?

[Linegeist]

Thanks gents - that lot helps ... well, a lot actually!

I remember reading your rather clever writeup Mister Mulley Sir - I tried to find it again, honest, but I gave up after half an hour.

Ta!

[mat_fenwick]

I tried to find it again, honest, but I gave up after half an hour.

Sorry, remind me what we are talking about?