Terrible Xantia brakes

Panjandrum · Post by **Panjandrum** » 10 May 2005, 02:53

Thanks for response - and especially on the wheeze.
I have just popped out to see if I really have a springy thingy under my pedal and sure enough I can feel something the shape shown in the pictures. I can't judge how compressible it is while it's still under the pedal. But design variation in the spring (stiff ones for the Activa) or production variations might well be an explanation? Maybe Saturday I'll see if it comes out as easily as you all suggest..... Just out of scientific curiousity you understand.
Oh yes, and I'll give mine a squeeze too just to see how hard it is[:D]

DoubleChevron · Post by **DoubleChevron** » 10 May 2005, 06:37

Actually I think the people that claim there brakes are good and see no reason to remove the spring ........... Probably already have the spring removed by a previous owner of the car !!!
When I mentioned the Xantia braking difference to Alan S is an email after removing the spring from mine he claimed his has better feel than the BX brakes .... Which is EXACTLY how they feel AFTER removal of the spring. Infact they feel just like an early DS button !! (ie: perfect). His spring has no doubt already been removed by a previous owner.
seeya,
Shane L.

macaroni · Post by **macaroni** » 10 May 2005, 13:07

Panjandram - my advice is to do it. I had to persuade my plunger to come out with the help of screwdriver, but the whole job took a few minutes. I too get a wheeze if I brake hard, similar to the wheeze I get when I turn the steering wheel.
This really is a fantastic mod and shame on Citroen for wimping out attempting to emulate a normal brake pedal feel.

Panjandrum · Post by **Panjandrum** » 10 May 2005, 14:28

My spring is definitely still there. I hope no-one is watching my driving this past couple of days. Any time there is an empty stretch of road they would see the car for no apparent reason slowing almost to a stop several times. Will have a go at replacing it later in the week and report back.

davek-uk · Post by **davek-uk** » 10 May 2005, 14:45

Used as I am to 'conventional' stamp-on-the-brake braking systems, I find the Xantia brakes brilliant - except when I stamp on them! Someone recommended that new hydro owners should get ABS and I'm beginning to agree. Every time I have had to use emergency braking I have locked the wheels - I'm just not used to such responsive brakes. And unfortunately you don't get a lot of practice of real emergency braking to quickly correct your style.
This leads me to another thought, more in tune with this thread: I'm wondering if it is 'old' Citroen hands that are complaining about the plunger (having been used to more direct braking) and newer Cit owners who accept it as they know no different. It's just a thought.
I like the idea of my brakes reacting quicker but, at the same time, I'm afraid of what I'd do with them if they were better!

paranoid · Post by **paranoid** » 10 May 2005, 16:24

I have just checked my springy thing......
There is definately a spring (can hear it) in there but the movement at the most is 5-6 mm seems like a very stiff spring nothing like the picture.
I raised another topic on this a week or so ago, non linear braking etc, bleeding the back brakes fixed the problem, but what seemed strange was that no bubbles came out till a clear 1 litre bottle was about 2/3 full and there was lots and lots of air, the same both sides

Post by **Thunderbird** » 10 May 2005, 16:50

From my personal experience with other cars, I must say Xantia brakes are really bad. [:(] I got used to the feeling of the pedal, the problem are the long braking distances.
I believe the reasons for this are of economical nature. Good brakes (mecahnical parts as discs, etc) are very expensive and that would impact the final Xantia price, making it less competetive with rivals.
The Xantia brakes are adequate for a 1000Kgs car and it weights around 1500Kgs!
It is true that most brands also have bad brakes at this segment, but Renault Laguna, BMW 3xx, and Lexus iS200 are three good examples that demonstrate a car this size and price can brake very well.
You can upgrade them (much larger discs, new ventilation system, new ABS program, etc, but that will cost a fortune, probably more than the comercial value of the Xantia!).
Just forget about driving sportively this car. [xx(]

Mandrake · Post by **Mandrake** » 10 May 2005, 16:58

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

I have just checked my springy thing......
There is definately a spring (can hear it) in there but the movement at the most is 5-6 mm seems like a very stiff spring nothing like the picture.
<hr height="1" noshade id="quote"></blockquote id="quote">
Ah, so there are different strength springs then. I thought so... the one I replaced was definately as soft as the animated picture implies. (Easily compressed in the palm of one hand)
<blockquote id="quote">quote:<hr height="1" noshade id="quote">
I raised another topic on this a week or so ago, non linear braking etc, bleeding the back brakes fixed the problem, but what seemed strange was that no bubbles came out till a clear 1 litre bottle was about 2/3 full and there was lots and lots of air, the same both sides
<hr height="1" noshade id="quote"></blockquote id="quote">
It's not so strange that the "air" could be trapped so far up the line - unlike conventional brakes the rear brakes on a Citroen are fed from the rear suspension, so there is a long pipe going from the rear height corrector junction all the way up to the front of the car, through the second section of the brake doseur, then all the way back down the car again to the rear brakes.
The main source of "air" is the nitrogen very slowly leaking (over months or years) from the spheres, which has no choice but to bubble into the oil. In the normal suspension paths this is no problem because every time the car goes up and down the bubbles are forced back to the low pressure resoviour where they bubble out into the atmosphere.
But any bubbles that head up that pipe towards the doseur valve will be following a dead end to the brakes with nowhere to bleed to...
Come to think of it, I'm not sure what effect having air in the brake line *before* the doseur valve would have compared to the more conventional case of having the air in the line *after* the valve. I suspect the results would be strange indeed.
Moral of the story: bleed those rear brakes [:D] especially after removing and refitting rear suspension spheres, as a significant amount of actual air will get in when that is done, and although most of it will return to the resoviour when the height control is exercised a few times, any that gets into the path to the rear brakes will stay there.
How many people bleed their back brakes as well as doing Citrorobics after replacing rear spheres ?
Regards,
Simon

Mandrake · Post by **Mandrake** » 10 May 2005, 17:08

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

From my personal experience with other cars, I must say Xantia brakes are really bad. [:(] I got used to the feeling of the pedal, the problem are the long braking distances.
I believe the reasons for this are of economical nature. Good brakes (mecahnical parts as discs, etc) are very expensive and that would impact the final Xantia price, making it less competetive with rivals.
The Xantia brakes are adequate for a 1000Kgs car and it weights around 1500Kgs!
<hr height="1" noshade id="quote"></blockquote id="quote">
While I agree that technically the design of the Xantia brakes is definately inferior to earlier Citroen's such as DS, GS and CX, being only a single piston caliper arrangment, I was amazed at just how well they DO work with the spring removed.
I would NOT say that the stopping distances are poor, in fact I would say they are excellent. And this is on my Dad's 1994 model which doesn't even have ABS.
Yes I can lock the front wheels if I deliberately try, but only in a full on emergency stop when I deliberately press far too hard, otherwise the brakes are extremely smooth, sensitive, and slow you very quickly with zero fuss. Also with the spring removed, rapid cadence braking to avoid skidding becomes possible, even easy, whereas with the spring I found it very difficult to achieve.
I'm curious, did you ever drive one with the spring removed ?
(BTW only the very heaviest models like the V6 even approach 1500Kg, a standard 2.0 is more like 1300Kg, still heavy admitedly)
Regards,
Simon

Kowalski · Post by **Kowalski** » 10 May 2005, 18:12

The brakes on my Xantias are absolutely fine, they aren't sports car / racing brakes but I've never had a problem with brake fade or overheating. The older Xantia I've got has the 266mm discs where as the newer one has the 283mm front discs and I can't tell the difference. Both cars will lock wheels easilly, the later one will lock all 4 wheels with the ABS chattering away unlocking them as you go....

daktari · Post by **daktari** » 10 May 2005, 18:40

Well. I had to get to the bottom of this `Are they, aren`t they better thing. So what i did was to replace the solid tube with a stronger spring than originally removed and take the car for a test drive. I found a nice stretch of empty road and then did a series of emergency stops and some less frenetic normal stops. The results were surprising. Apart from having a very slightly stiffer pedal initially, the actual braking effort required was reduced from the original (softer) spring, still nowhere as good as the solid tube that is now fitted though. So it would appear that Citroen did at some stage change the spring for a stiffer item. I`ve now put the solid tube back in and must say i`m much happier with that there. [:D]

rbruce1314 · Post by **rbruce1314** » 10 May 2005, 19:33

<blockquote id="quote">quote:<hr height="1" noshade id="quote">
Also worth considering is that the brake doseur is an EXTREMELY reliable piece of equipment, and in all the Citroen's I've known I've never known one to fail or even behave slightly strangely.
<hr height="1" noshade id="quote"></blockquote id="quote">
sorry to spoil things Mandrake but I had a doseur valve go on my Xantia at 15k! Complete failure, no brakes, LHM all over carpet. Although out of official warranty, Citroen did replace it for free, but did not go so far as to replace carpet!

Post by **Thunderbird** » 10 May 2005, 19:34

My Xantia HDi weights 1574 Kgs [V] and 1900Kgs with five passengers.
On the same road, from 100km/h to 0km/h it needs about more 10 meters than a Saxo 1.6 16V with original brakes and 20 meters [:0] than the same Saxo with improved brakes (330mm discs in the front if I recall, 980Kgs).
Now, the Saxo 1.6 16V suspension is much better than the Xantia when braking - extremely fast acting and the body remains absolutely stable in any direction when braking hard. Xantia suspension targets ride comfort.
Now, my Xantia still has the spring - I think I will consider removing it and see the results...

JohnCKL · Post by **JohnCKL** » 10 May 2005, 20:37

I mentioned this to my mech who's a specialist in Cits. He's owned and driven DS, GS, CX, SM, BX, XM and Xantia. He said he's got no complaint for Xantia's brakes, they're just fine and he fixes Cits for a living. However, since its easy to try out, maybe I'll give it a go.

paranoid · Post by **paranoid** » 10 May 2005, 22:34

I worked as a mechanic for nearly ten years at a very busy workshop with a lot of different cars,but especially more BX's Xants 306's 406's etc And I have to say that Citroen Hydraulic brakes are really some of the most powerfull I have used in everyday driving, In fact only more powerfull was on a BMW M5
My first Xantia (one of the last old shape 97 TD) had very good brakes, This showed up the problem with my new Xant (98 TD) I knew straight away that something was amiss, with the forums help I fixed the problem.
Although I do wonder where the air was in the system 2/3 of litre before the air came out makes me wonder where it had got stuck[:)]
Will investigate tommorow with workmates Xant to see if spring is weaker.