BX Steering lockup

tcb123 · Post by **tcb123** » 29 Dec 2003, 16:29

Hi All,
My BX has developed a nasty habit of making the steering very stiff, but only sometimes! almost as if the power steering is locking up!
where should I start looking for this one?
regards
Tom

alan s · Post by **alan s** » 29 Dec 2003, 17:49

Start by running Hydra flush through the hydraulics. Doesn't always cure it but the fact that it's intermittent says it could be crap & contamination in the system clogging filters.
If the oil (LHM) looks more like engine oil than a bright green, that's the obvious clue to this as a starting point.
Alan S

mjcottle · Post by **mjcottle** » 29 Dec 2003, 23:27

I had a old high mileage BX (I bought it at 125K, Just about run in! I sold it at 208K and it went on another 4 or 5 years)which did the same. When talking to my local Citroen garage they sold me a new Hydraulic control valve which is intended to cut off the 'users' of hydraulic oil when (due to a fualt) the pressure is dropping to a very low value and thus only feed the brakes (I think from memory) for safety reasons.
This was vey expensive for a block with just a pressure valve in and did not cure the problem! The problem was, I belive, that the powersteering control valve that is mounted on the steering rack between the rack and the steering column was leaking in some positions and thus losing the power assitance. I lived with this as the hassle of removing the rack from the car etc etc.
But a <u><b>warning</b></u> if you do the same and you lose the power steering effort in a bend you could crash the car! The increase in effort required without power steering is very large and may be impossible to overcome.
I have heard of a new Ford that had problems with the power steering, the garage concerned did not agree (the cistomer is never right!) and when one of their mechanics was testing it, the steering failed and they wrote off the car!

AndersDK · Post by **AndersDK** » 30 Dec 2003, 00:19

The component responsible for this servosteering problem is the FDV (Flow Divider Valve) - fitted to all BX'es with servosteering - and Xantia & XM up to modelyear approx '95.
As AlanS explains the problem MAY be fixed by using the Hydracleanse fluid in the hydraulics system. But at times the problem has developed to such an extent that the FDV must be either overhauled or replaced.
Using the hydracleanse fluid means a complete replacement of the hydraulic fluid - a description on this work may be found here :
http://citroenz.com/forum/viewtopic.php?t=27
mjcottle :
Unfortunately you have experienced a totally incompetent garage - trying to fix the problem by replacing the safety/priority valve - which has NOTHING to do with the servosteering.
The steering rack fitted pinion control valve will not make for such servosteering symptoms - as leaking from this valve tends to develop slowly and then slowly over time make the steering heavier.
The sudden fall out of the servopower is symptomatic for a failing FDV - and YES indeed quite dangerous.

DomF9 · Post by **DomF9** » 03 Nov 2004, 01:49

Hi all
Can someone on this thread give me some advice. I've just bought an XM and the steering meets resistance about every third of a turn in both directions. Thought it was the columm and uj out of alignment, but now not so sure.
Any thoughts please?

tomsheppard · Post by **tomsheppard** » 03 Nov 2004, 14:04

That sounds like low pump pressure and is quite characteristic of a slipping pump belt,(First check) or worn out LHM. Often it feels worse at startup and improves as the fluid warms up or the belt does and grips better. Worst case-worn pump.

wrinklet1 · Post by **wrinklet1** » 03 Nov 2004, 14:15

I had thje same problem with my old Bx, tried Hydroflushing, Tightening the pump belt, My car would be okay and then suddenly for about a second the assitstance would go.
The power steering runs on low pressure and suspension and brakes on high pressure, first to go is low pressure
I ended up talking to a Citroen expert and he said that it was typical of a tired HP pump.
I changed my HP pump and hey presto, the car was totally different.
Paul

Dave Burns · Post by **Dave Burns** » 04 Nov 2004, 00:06

If its just going stiff because of no power assistance, i.e heavy then yes FDV or pump are prime suspects, but if it is actually locking near solid just momentarily it could be the ram.
If this happens when the car is moving at a reasonable speed then even with no power assistance the steering wont feel that much heavier, not like if the car was stationary when the steering would then feel very heavy.
Iv'e known two rams go down this way on ZX's, it gets progressively worse and very dangerous, when the steering begins to lockup turn it sharply the other way just a few degrees, if it clears and then will continue in the original direction suspect the ram, this is what happened with the ZX's.
Dave

DomF9 · Post by **DomF9** » 04 Nov 2004, 02:46

The resistance happens in the same place every time - a third of a turn of the wheel, all the time, in both directions. It's a real pain when you try to make a right or left turn, as you have to turn the wheel beyond the resistance point to avoid crossing the centre line, traffic island or pedestrians. Unfortunately it means you have to exert more elbow grease into turning the wheel beyond the resistance, and suddenly it's in full lock, more or less, and you have to suddenly go through the same procedure in reverse just to straighten the wheels without finding yourself across the pavement or opposite lane.
All belts seem to be tight and fine, but it just sounds like one of virtually anything.