CItroen BX hissing sound

wonderd · Post by **wonderd** » 08 Jul 2004, 17:24

my 1991 bx makes a very annoying hissing sound every 2 seconds and if the engine is running in a low RPM then the sound kepps steady.
what is that?? how do I stop it?

uhn113x · Post by **uhn113x** » 08 Jul 2004, 18:18

Hi Wonderd
I wondered (sorry!) how long have you had the car, and has this just started?
What do you mean by 'if the engine is running in a low RPM then the sound kepps steady'? What happens at high RPM?
The only hissing I can think of is that when the pressure regulator cuts in, which should last a few seconds and end with a click. This is normal, but should not be every few seconds; if it is, the accumulator sphere is duff.
If there is a hiss and no click, the non-return ball valve in the PR needs reseating.
Can you tell where the hiss is actually coming from?

jeremy · Post by **jeremy** » 08 Jul 2004, 19:42

Your noise sounds like the pump/regulator noise. There should be an occasional noise followed by intervals of silence. What is happening is that the regulator is not achieving a proper cut off possibly due to low output from the pump.
You don't say what model of BX you have and so I don't know if it has power steering or not. While its not a comprehensive test if the PAS is functioning properly at all speeds then the pump is probably adequate. If its part-time then the pump could be suspect (along with the FDV but thats probably not the problem here)
The regulator should cycle more slowly than it does. Try dropping the car using the height control and see if there is any difference. If things change (and get slower) then there is an internal leak in the suspension or the rear brakes.
If not then your accumulator may well be flat. Raise the car to normal height and turn off the engine. Open the tailgate and sit in the boot. the car should sink, and then after about 20 seconds rise to its original height. If it does so the power can only come from a functioning accumulator. If it doesn't then your accumulator is flat and needs replacing.
If with a good sphere it still does this then the non-return ball valve needs re-seating. Instructions are in the handy tips section of this board.
jeremy

wonderd · Post by **wonderd** » 09 Jul 2004, 02:16

Thank you both, I have 1.6L tzs 1991 BX, with power steering, I have it for almost two years and I have been living with that problem from day 1.
Even if I lower the car and the engine is idle (around 10,000 rpm) the sound continues without any intervals, but if I raise the rpm above 13,000 then there is intervals of 2 seconds, there is no click after the sound.
I think the sound (the hissing) comes from around the pressure regulator.
I also have 2 more problems:
1. when I turn off the engine, the car starts lowering almost immidiatly.
2. when I turn the steering wheel just a little bit, there is a sound that sounds like pressure release.

uhn113x · Post by **uhn113x** » 09 Jul 2004, 12:51

<blockquote id="quote"><font size="1" face="Verdana, Arial, Helvetica" id="quote">quote:<hr height="1" noshade id="quote">Even if I lower the car and the engine is idle (around 10,000 rpm) the sound continues without any intervals, but if I raise the rpm above 13,000 then there is intervals of 2 seconds, there is no click after the sound.
<hr height="1" noshade id="quote"></blockquote id="quote"></font id="quote">
Cor! [:0][:0] How much do you want for your engine? Is it RR or Pratt and Whitney? Always fancied a jet in the ZX [;)]
Changing the subject, if the hiss actually stops periodically without a click, then I would try reseating the ball first - check accumulator as described by Jeremy first, as you have to remove it to get to the ball. Is pump belt tight? Is LHM absolutely clean (veddy, veddy important)

jeremy · Post by **jeremy** » 09 Jul 2004, 13:15

before you go any further have a look at the thick hose between the reservoir and the pump. the hissingnoises that happen when you turn the wheel suggest that there may be air getting in and about the only place it can is through this hose, which usually fails at the joints but can even perish and go porous in between.
Anders suggests a temporary replacement with a (Clean) section of garden hose!
If this is a porblem you may be able to see bubbles in the reservoir or a green milky emulsion. There should be no bubbles or emulsion.
Jeremy

wonderd · Post by **wonderd** » 09 Jul 2004, 13:35

where can I find those handy tips?

jeremy · Post by **jeremy** » 09 Jul 2004, 13:43

You have in fact passed them on your way in. Go to 'All forums' (Link under Andyspares logo at top of this page) and its 2 or 3 on the menu.
Jeremy

wonderd · Post by **wonderd** » 09 Jul 2004, 14:17

Well, I cant find how to do it in the hints section, maybe you can explain it to me?

jeremy · Post by **jeremy** » 09 Jul 2004, 14:44

Try this one
http://www.andyspares.com/discussionfor ... ,regulator
I thought it was in hints - must write to Jon!
Jeremy

wonderd · Post by **wonderd** » 09 Jul 2004, 16:39

Thanks,
can I do this operation without removing the regulator?
Could I get to the ball by only removing the sphare?

jeremy · Post by **jeremy** » 09 Jul 2004, 18:27

Have done it on my DTR turbo (same car as TZD Turbo. Regulator is on front of engine fastened near starter, with small gap to radiator. I think yours is in the same position. I did it from underneath with no access needed from top except to undo release valve. (Bolt on front - just loosen - DO NOT UNDO!). Be prepared for the ball bearing to drop out and have something in place to catch it! (tray? - don't use your eye!)
Usual precautions of course - remember these cars CAN KILL!
jeremy

wonderd · Post by **wonderd** » 09 Jul 2004, 19:03

Thanks, it's located in the same place.
I just finished removing the whole regulator.
Now maybe i can clean the regulator first and and overhall it.
now it should be easy to catch the ball...

wonderd · Post by **wonderd** » 09 Jul 2004, 19:13

O.K., problem..
there is no ball!!!
where is it suppose to fall from exactly??

uhn113x · Post by **uhn113x** » 09 Jul 2004, 22:00

If you unscrew the accumulator sphere from the regulator, and look at the bottom of the recess it came from, you will see a slotted plate held in with one screw. Remove plate and screw, ball is underneath. Lift/shake it out - if it is corroded, renew it. Put the old or new ball in, give it a sharp tap with a brass (never steel) drift to seat it, replace plate and screw, and sphere. Take care not to disturb the main valve spool held in by the plate.
That is all the 'overhall'-ing you can do to a PR.
HTH