Xantia MK2 rear brakes

juppy · Unread post by **juppy** » 02 Jul 2008, 05:52

Due to a horrid grinding noise ( OK it has gone down to the pad backing) eminating from the rear nearside, I am going to fit new pads and discs. I just have a few questions.

The car is a T reg facelift Xantia 1.9TD hatch.

1 The manual says you have to depresurise the system, why? as far as I can see you are not splitting any hydraulic joints.

2 Taking the fact that you do have to depresurise the system as gospel, where is the bleed screw/bolt that is referred to in the manual as it does not say, nor is there a picture / diagram.

3. The text also says once the calliper is off you have to undo the disc retaining screw, all I can see is the little stud that helps align the wheel so the stud holes line up, is this one and the same thing, i.e. it does both functions.

Any help tips and or advise would be most welcome, as when I work on moderern cars it only goes to remind me why I like classic cars so much

Garth

reblack68 · Unread post by **reblack68** » 02 Jul 2008, 07:31

1. I can't remember depressurising the system when I did mine but I think the only thing that holds the calliper together is the bolts that you are going to remove. Maybe it's so that you can force the pistons back.

2. The bleed screw is beside the accumulator sphere. It just looks like a 12mm bolt head. It's like letting down a hydraulic jack.

3. Yes

4. (what do you mean you didn't have a question 4?) When I did mine three of the four bolts broke in the hub. This is caused by corrosion in the mating face of the calliper which puts strain on the bolts. If the pads are wedge shaped this is likely to happen to you.

5. Before refitting scrape said corrosion off both faces.

Apart from the likelihood of the bolts breaking it's a dead easy job

Unread post by **RichardW** » 02 Jul 2008, 07:49

No need to depressurise for brake work.

As noted you will probably find corrosion behind the caliper causing it to twist. I've been lucky in that I've done two, one of which was very rusty, and I've managed to get all 8 bolts out. You can get to the back of the bolts - give them a clean and some Plus Gas, then go very very gently with the bolts, working them in and out so they don't snap. You can do the corrosion removal with the pipe still attached, but it is a bit of pain. Remove the pads first, then refit the small pas bolt before removing the caliper - this stops it falling in half. make sure you clean the caliper well, and put plenty of copperslip on the pads - this should help to keep things mobile back there.

davek-uk · Unread post by **davek-uk** » 02 Jul 2008, 10:40

Behind the calliper make sure you clear off all the corrosion. I used a thick sheet of plastic (part of a builders sheet) to put between the suspension arm and the calliper. Four years later I have no corrosion. A similar barrier seems the best way to go for longevity.

Dave

Unread post by **myglaren** » 02 Jul 2008, 11:03

I used a thick sheet of plastic (part of a builders sheet) to put between the suspension arm and the calliper. Four years later I have no corrosion.

I contemplated on this when I had the C5's rear calipers refurbished and wondered if there was a reason they didn't fit a similar gasket here from new. Cheap and easy solution to an obvious problem.

Unread post by **CitroJim** » 02 Jul 2008, 12:41

Have the caliper right off to clean it. Don't try to do it with the caliper dangling on the end of the hydraulic pipe. Get some 3.5mm hydraulic seals first so you can replace them, never a good idea to use the old ones as they WILL leak.

Beware that the corrosion on the caliper face can be very hard and look like part of the caliper. I've had to use a cold chisel in the past to make a good job of cleaning the corrosion off

juppy · Unread post by **juppy** » 04 Jul 2008, 06:12

Where do the 3.5mm seals go? and following the manual I can't see that I have to break anything or disturb any seals.

Xaccers · Unread post by **Xaccers** » 04 Jul 2008, 10:10

juppy wrote:Where do the 3.5mm seals go? and following the manual I can't see that I have to break anything or disturb any seals.

It goes in the hole that the hydrolic pipe comes out of when you remove the caliper to clean it.

davek-uk · Unread post by **davek-uk** » 07 Jul 2008, 10:22

myglaren wrote:
I used a thick sheet of plastic (part of a builders sheet) to put between the suspension arm and the calliper. Four years later I have no corrosion.
I contemplated on this when I had the C5's rear calipers refurbished and wondered if there was a reason they didn't fit a similar gasket here from new. Cheap and easy solution to an obvious problem.

That would assume that Citroen acknowledge there is a problem and that they have feedback from their service departments. It would make things easier for us older car owners though. But when have any car manufacturers thought of the life of their products after the 3-5 years of corperate ownership?

Dave