Pressure Reg ticking too much

Chrispy · Post by **Chrispy** » 10 Jun 2005, 02:40

Hi all,
Got a few issues, and I'm seriously starting to regret buying a Xantia now as the suspension/ braking system is just daft.
Firstly, when starting the car sometimes, the front suspension will drop suddenly and makes a loud grating/clattering noise (like dragging a stick over a cheese grater. It then pumps back up and all is well. The front pumps up in jerks too, whereas the back is smooth, so I'm gonna lubricate the front struts at the weekend to see if it fixes it.
Also, my pressure regulator is ticking far too often, like every 5 seconds at idle at normal height. I had my accumulator sphere changed last week and that made it even worse (it was every 10 - 12 seconds before). Any ideas? I don't wanna go chucking money at the problem as I bought this thing to save £££ not the other way around.
My brakes also feel quite feeble and sometimes a bit wavy. When I say wavy, I mean that they feel like they're slowly grabbing a bit harder then easing off a bit again. It's not warped discs as I've had that many times on other cars....this is waaaay to slow for that but it does cause you to lurch back and forth when braking on slip roads as the brakes can't make up their mind how well to work.
Any ideas guys before the thing goes back in Autotrader?
How do I diagnose the hydraulic system? the Haynes manual is totally useless. [V]
Cheers,
Chris.

tanto · Post by **tanto** » 10 Jun 2005, 03:04

did you bleed the hydraulic system after changing the sphere if not then you may have air trapped in the system do a search on the forum for this as it has been discussed on here before you should be able to find a post that will tell you how to do the bleed procedure

JohnT · Post by **JohnT** » 10 Jun 2005, 03:34

This may be off the wall but try this previous post.....it worked for me,
System bleed
I've been using it's recommended bleed procedure: ``drop the height lever inside the car, with the engine running, slacken the 12mm bleed screw on pressure regulator after car settles until `whistling stops’ then retighten screw…
But I've since seen on here some variations: same as above with door/boot open…
And also: when the suspension needs to be bled,the lever in the car needs to be at the highest position,engine running at idle,undo the "bleed screw" 1/4 turn,leave about 3 minutes and then tighten(NIP ONLY) the bleed screw.then lower the lever to its normal position,the suspension is now bled correctly!!.
Let us know if this helps!

Mandrake · Post by **Mandrake** » 10 Jun 2005, 09:36

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Chrispy

Hi all,
Got a few issues, and I'm seriously starting to regret buying a Xantia now as the suspension/ braking system is just daft.
<hr height="1" noshade id="quote"></blockquote id="quote">
Like any second hand car, there may be problems if the car hasn't been looked after properly. I wouldn't call the suspension and brakes "daft"...but because not a lot of people understand how they work, its more likely to be in poor condition in a second hand car, if it hasn't been well maintained...
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
Firstly, when starting the car sometimes, the front suspension will drop suddenly and makes a loud grating/clattering noise (like dragging a stick over a cheese grater. It then pumps back up and all is well. The front pumps up in jerks too, whereas the back is smooth, so I'm gonna lubricate the front struts at the weekend to see if it fixes it.
<hr height="1" noshade id="quote"></blockquote id="quote">
Definately lubricate the struts first, but the front lifting up in jerks can also be contributed to by a faulty pressure regulator sphere, as it causes the anti-sink valve to keep opening and closing as the system is pressurized instead of opening once. A faulty pressure regulator sphere also may cause the front to drop then rise again as you first pressurize the suspension.
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
Also, my pressure regulator is ticking far too often, like every 5 seconds at idle at normal height. I had my accumulator sphere changed last week and that made it even worse (it was every 10 - 12 seconds before). Any ideas? I don't wanna go chucking money at the problem as I bought this thing to save £££ not the other way around.
<hr height="1" noshade id="quote"></blockquote id="quote">
It sounds like there is something wrong with the pressure regulator sphere, despite the sphere being changed, (maybe DOA ?) or there is an internal pressure leak somewhere - possibly the ball valve on the pressure regulator bleed screw has a bit of grit under it preventing it from closing completely.
There was a thread recently describing that. Although I've never done it myself I believe you can depressurize the suspension and regulator, then remove the release bolt completely, being careful not to lose the steel ball when it falls out, (there may be a little oil pressure trying to push it out) then make sure the seat is clear of foreign objects then refit it.
To check the pressure regulator sphere is ok, (and that the release valve isn't leaking - both will have to be ok to pass this test) try the test I describe in the last message on this page:
http://www.andyspares.com/discussionfor ... C_ID=14251
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
My brakes also feel quite feeble and sometimes a bit wavy. When I say wavy, I mean that they feel like they're slowly grabbing a bit harder then easing off a bit again. It's not warped discs as I've had that many times on other cars....this is waaaay to slow for that but it does cause you to lurch back and forth when braking on slip roads as the brakes can't make up their mind how well to work.
<hr height="1" noshade id="quote"></blockquote id="quote">
This is also a fairly prominent sign that despite replacing the accumulator sphere, it might be a dud.
Without the gas in the accumulator sphere, every time the pump cuts in and out, the pressure supplied to the front brakes will jump up and down dramatically, so when you brake hard the braking efficiency will fluctuate a lot, in time with the pump cutting in and out. With the regulator sphere gassed up properly, the pressure fluctuations are smoothed out to an imperceptable level.
(Just as importantly, the accumulator sphere, when in good order, provides enough pressure supply to operate the brakes a couple of dozen times after the engine is turned off. If it's completely faulty you'll have very little braking with the engine turned off - mainly only back brakes, so it's also a safety issue)
Also after that is sorted out, you might want to perform the following small modification to remove the "silly spring" from the Xantia's brake pedal:
http://www.andyspares.com/discussionfor ... C_ID=11689
This spring can cause it to be extremely difficult to regulate the stopping effort smoothly, you tend to over and under correct, after removal of the spring the brakes are the sensitive and accurate brakes that earlier Citroen's had...
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
How do I diagnose the hydraulic system? the Haynes manual is totally useless. [V]
<hr height="1" noshade id="quote"></blockquote id="quote">
Amen to that... the Haynes Xantia manual isn't worth the paper its written on. If you give good detailed info here, I'm sure people will be able to help you...
Regards,
Simon

macaroni · Post by **macaroni** » 10 Jun 2005, 13:15

I, amongst many others, dismayed at the Xantia's strange brake pedal have effected this mod of replacing the spring with a metal tube and the improvement is astonishing. Well worth it.

Kowalski · Post by **Kowalski** » 10 Jun 2005, 14:44

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by macaroni

I, amongst many others, dismayed at the Xantia's strange brake pedal have effected this mod of replacing the spring with a metal tube and the improvement is astonishing. Well worth it.
<hr height="1" noshade id="quote"></blockquote id="quote">
This has been discussed quite a bit hasn't it?

Chrispy · Post by **Chrispy** » 10 Jun 2005, 14:55

It's possible that the stupid springy thing is to blame for my brakes then I guess. It's been making funny noises recently when pressed gently so I'm tempted to rip it out. I don't have many tools so welding up a modified rod is kinda out of the question.... Might have a stab at it though at the weekend with the bits that I do have! I'm gonna grease the front struts and douse the height correctors in WD40 and L2 grease too. Also, I'm gonna check the condition of the LHM.....if it's brown then it's time for a flush. Chances are it's never been replaced. The rear anti sink sphere has never been replaced either so I'm tempted to get that changed if it'll help? If that 'rob's pressure from the system when the engine is started then that may account for the sudden sink sometimes?
I have noticed though that the ride height at the front seems high. The gap between the wheel and the arch seems a bit much.... Sticky height correctors and struts perhaps?

Post by **CitroJim** » 11 Jun 2005, 00:27

Thanks for submitting this question Crispy. Mine exibits all the same symptoms as yours, albeit to perhaps a lesser degree. I have a new accumulator sphere and I'm going to swap it at the weekend to see if theres any difference. Mine is supposed to be new I only have the word of the seller on that. I got a new one from a place that cannot be mentioned on this forum and it's date code suggests it's getting on for a year old so we'll see.
Mine seems high at the front and a tad low at the back to me. Is there a set of measurements that can be used to prove this point although I'm running non-standard 15" wheels and 60 profile tyres on mine so it may not help much... Can the ride heights be adjusted at all?

jeremy · Post by **jeremy** » 11 Jun 2005, 01:04

Firstly 2 easy tests for the regulator/acumulator. Raise the car fully and see if the ticking decreases - in effect you are using the suspension spheres as accumulators and it should slow. the next one is to put the car at normal height, turn off the engine and sit in the boot. the car should drop 4 or 6 inches and then after about 30 seconds rise to its original height. If it does this twice the accumulator is really good, once probably ok.
Frequent ticking of the system can be caused by a leaky non-return valve in the regulator itself. Its situated under a flat metal plate secured by a single small bolt on the face under the sphere. To reseat (you may be able to do it on the car - I have done it on my BX TD) remove the bolt and the plate and collect the ball, stick it back in the hole with a dab of grease if necessary and tap it smartly using a BRASS (steel will put a flat on it) punch. re-assemble.
That the ticking has got faster since the LHM was changed makes me wonder if the ball bearing valve under the pressure release screw has been lost. this bolt should only be undone 1 or 1 1/2 turns max but if its remeoved the ball bearing will fall out. Worth a look as it would explain many of your problems and isn't expensive.
I'll try and post a link to some of the BX parts book - I think the ball size is in the regulator section.
Cant find link - Anders posted it recently and a search may reveal it. Non return valve is a 6mm ball and pressure relief valve is a 7mm for BX and xantia is probably the same. To get one ball bearing may be a problem but many years ago I needed about 3 and found a motor cycle repairer with a tin of odd ones!
Jeremy

Chrispy · Post by **Chrispy** » 11 Jun 2005, 23:19

Right, an update. I greased the front struts (which ate loads of grease), and doused the height correctors (I think that's what they were) with WD40 and coated em with grease. I also removed the spring from the brake pedal and replaced it with a section of 15mm copper pipe of equal length. My brakes are now very fierce and the travel is tiny...about an inch tops!
Now, my symptoms are as follows after some testing:
When I raise the car to full height, during raising the ticking stops......but once at maximum height it ticks frantically (tick tick tick tick) like 3 times a second, then gradually slowing down to tick every 8 seconds or so. I bled the regulator (LHM went all over my drive) and heard no hissing from the accumulator sphere when I did. Should I have done? The pressure regulator ticks every 5 seconds when at normal height or fully dropped.
When fully dropped, ad I move the lever to the max height position, it takes aaaaages before the car starts to move up. The ticking stops straight awa, but the car doesn't start to rise for about 10 seconds. Then the rear goes first to the top, followed then by the front in jerks until it hits the top and then the ticking goes mental as mentioned in the above paragraph.
The LHM hasn't been changed by me (unsure about previos owners) but the garage replaced my acc sphere. Now, whether he used the proper one and not an axle one I don't know as he's a BMW specialist not Citroen. If anyone knows of one in West Yorkshire please tell me!
It is a nice green though as I spilled some today from the bleed screw...doh!
I've checked the 2 return lines to the top if the LHM tank and their not even dripping whilst the engine is running so I doubt it's an internal leak. Would replacing the anti sink sphere at the rear aswell as the accu sphere (again) help? Seeing as though the car sinks (sometimes quite rapidly accompanied by a chattering noise) when you start it I'm wondering if it'll help.
Any ideas guys? I'm stuck!!! Help!!
Cheers,
Chris.

Chrispy · Post by **Chrispy** » 11 Jun 2005, 23:23

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by jeremy

Firstly 2 easy tests for the regulator/acumulator. Raise the car fully and see if the ticking decreases - in effect you are using the suspension spheres as accumulators and it should slow. the next one is to put the car at normal height, turn off the engine and sit in the boot. the car should drop 4 or 6 inches and then after about 30 seconds rise to its original height. If it does this twice the accumulator is really good, once probably ok.
Frequent ticking of the system can be caused by a leaky non-return valve in the regulator itself. Its situated under a flat metal plate secured by a single small bolt on the face under the sphere. To reseat (you may be able to do it on the car - I have done it on my BX TD) remove the bolt and the plate and collect the ball, stick it back in the hole with a dab of grease if necessary and tap it smartly using a BRASS (steel will put a flat on it) punch. re-assemble.
That the ticking has got faster since the LHM was changed makes me wonder if the ball bearing valve under the pressure release screw has been lost. this bolt should only be undone 1 or 1 1/2 turns max but if its remeoved the ball bearing will fall out. Worth a look as it would explain many of your problems and isn't expensive.
I'll try and post a link to some of the BX parts book - I think the ball size is in the regulator section.
Cant find link - Anders posted it recently and a search may reveal it. Non return valve is a 6mm ball and pressure relief valve is a 7mm for BX and xantia is probably the same. To get one ball bearing may be a problem but many years ago I needed about 3 and found a motor cycle repairer with a tin of odd ones!
Jeremy
<hr height="1" noshade id="quote"></blockquote id="quote">
I sat in the boot with the ignition off and it just sinks a few inches....no rising. To be honest wont the rear suspenson be isolated anyway by the anti sink valve?
If I do need to replace the regulator, is it expensive? It's ticking like hell at the mo and didn't hiss when I opened the bleed valve. It just spat LHM everywhere instead.

Post by **CitroJim** » 11 Jun 2005, 23:51

I swapped my accumulator sphere today Chrispy. Things are a little better. I get two "rises" now when I do the "sit on the tailgate" test! That was after a good bout of Citarobics.
Not sure how significant it is but my front always rises first... Mine is a non-anti-sink do it may be a bit different on these.
TBH, it still sounds like your accumulator is not holding anything if you did not get the LHM "rush" when you opened the release valve. Worrying too that a load of LHM spat out. None should when you open the valve and I lost only about half an eggcupful when the the old accumulator came off. If you have not already done so, put another accumulator on before doing anything else. If you're anywhere near Milton Keynes I have one you can try... Also, I wonder if the ball under the release valve is missing. That could cause it.
Hope you soon get this sorted. Xantias are great when they work properly so it's worth persevering...

Mandrake · Post by **Mandrake** » 12 Jun 2005, 06:08

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Chrispy
I bled the regulator (LHM went all over my drive) and heard no hissing from the accumulator sphere when I did. Should I have done? The pressure regulator ticks every 5 seconds when at normal height or fully dropped.
<hr height="1" noshade id="quote"></blockquote id="quote">
How much did you turn the bleed screw ? Normally you would only turn it a quarter of a turn. Certainly no more than half a turn. If oil leaked out around the bleed screw after only turning it this much it is almost certain that the ball bearing is missing.
The bleed screw should NOT leak any oil whatsoever, and it should never be opened more than half a turn, and certainly not unscrwed right out. If it has been previously unscrewed right out, its an almost certainty that the ball has been lost, and that could be one of your major problems.
Without the ball, the valve will not seal correctly even when fully tightened, and pressure will keep leaking away even if the accumulator sphere is ok.
Refer to jeremys post for details on what size ball to replace it with if its indeed missing.
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
The LHM hasn't been changed by me (unsure about previos owners) but the garage replaced my acc sphere. Now, whether he used the proper one and not an axle one I don't know as he's a BMW specialist not Citroen. If anyone knows of one in West Yorkshire please tell me!
It is a nice green though as I spilled some today from the bleed screw...doh!
<hr height="1" noshade id="quote"></blockquote id="quote">
In your original post you said that the regulator ticking became more rapid after the sphere was replaced by this garage - that probably means only one of two things - a dud sphere, or they unscrewed the bleed screw fully, not understanding how it works, and lost the ball bearing from it.
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
I've checked the 2 return lines to the top if the LHM tank and their not even dripping whilst the engine is running so I doubt it's an internal leak. Would replacing the anti sink sphere at the rear aswell as the accu sphere (again) help? Seeing as though the car sinks (sometimes quite rapidly accompanied by a chattering noise) when you start it I'm wondering if it'll help.
<hr height="1" noshade id="quote"></blockquote id="quote">
Not sure what you mean by "not even dripping" as the return hoses going to the tank are usually FULL of oil all the time.
Regards,
Simon

Mandrake · Post by **Mandrake** » 12 Jun 2005, 06:19

<blockquote id="quote">quote:<hr height="1" noshade id="quote">Originally posted by Chrispy
I sat in the boot with the ignition off and it just sinks a few inches....no rising. To be honest wont the rear suspenson be isolated anyway by the anti sink valve?
<hr height="1" noshade id="quote"></blockquote id="quote">
No, this is the whole point of the test - the anti-sink valves are held open by the pressure from the main accumulator at the front of the car.
Normally the regulator pressure is 170 bars, but when that pressure drops below a certain threshold, (which I don't actually know, but lets assume that its somewhere around 100 bars) then the anti-sink valves close, isolating the suspension.
With a good accumulator sphere, it can supply enough oil to make a small height correction to the rear suspension one or two times, whilst still maintaining the pressure in the regulator higher than that needed to keep the anti-sink valves open.
When you stop the car and leave it alone, the sequence of events is that the suspension slowly loses height (it may take a few hours if the system is good) until there is enough error in the height (about 10mm) for the height corrector to attempt to correct the height. If at this point there is still sufficient pressure in the regulator, the car will lift slightly. Chances of you looking at the car at the exact moment this happens are slim, so people don't realise that it happens [:)]
This may happen a few times over 24 hours or so until there is no longer enough regulator pressure, then the anti-sink valves close, and the leakage rate is cut to a small fraction of what it previously was, and the height of the suspension will slowly drop over 5-10 days.
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
If I do need to replace the regulator, is it expensive? It's ticking like hell at the mo and didn't hiss when I opened the bleed valve. It just spat LHM everywhere instead.
<hr height="1" noshade id="quote"></blockquote id="quote">
It seems pretty clear that the ball bearing must be missing from the bleed valve, so you just need to bite the bullet and follow the suggestions from everyone here telling you to check and replace that missing ball [:D]
A small steel ball is likely to be somewhat cheaper than an entire pressure regulator [;)] (Which very seldom go wrong, I might add)
There may also be an o-ring on the shaft of the bolt that is missing or damaged too, but I'm not sure on that as I've never actually had to remove the bolt before. (The only time you would, is replacing a ball someone else had lost) Does anyone else know if there is also an o-ring on the bleed screw bolt ?
Regards,
Simon

jeremy · Post by **jeremy** » 12 Jun 2005, 12:10

The BX diagram I consulted for the ball size shows an 'O' ring for the bolt.
Mandrake you are absolutely right - I'm sure the ball is missing from the bleed screw. Somewhere I think there is a reference to LHM coming out which suggests the screw has been removed.
The valve on the regulator is provided to enable the accumulator to be collapsed to enable the system to be worked on safely and also to allow the pump to purge itself of air on re-filling after work. All that needs to be done is to open the valve, prime the pump and start the engine and after about 1 or 2 minutes shut the valve and the car should rise from the floor!
Bleeding is not a critical process, most of the air will be expelled by 'Citroebics'. The real thing is to get the pump primed.
jerermy