C5 Red Hot Brake Disc

KevMayer · Post by **KevMayer** » 27 Dec 2008, 10:28

Happy Christmas to everybody.

On Christmas day I travelled 12 miles to see some friends. I noticed the C5 seemed reluctant to pick up along the way, but, when we arrived we could smell something like clutch burning. We then saw smoke rising from the front left wheel.

We all got out and I could see the front left brake disc glowing bright red hot. All the other discs were ok.

I let it cool down and when I came to drive it later it was all ok again.

Could this be a hand brake cable problem ? Or, maybe the ESP had been applying that brake for some reason ? There was no ESP/ASR light lit up on the dash.

Post by **CitroJim** » 27 Dec 2008, 10:46

Nasty Kev

Check you don't have a binding handbrake cable. The outer sheath might have split in the guide rings, let water in and caused it to partially seize.

The set-up is, as I understand it, much the same as a Xantia as far as the handbrake goes and suffers all the same problems.

den169 · Post by **den169** » 27 Dec 2008, 11:12

Iv'e had the same problem myself about a year ago.mine was the little lever with a spring on it on the back of the caliper,I managed to free it off get some grease on it and its been fine since.

KevMayer · Post by **KevMayer** » 27 Dec 2008, 14:49

Thanks Jim and Den.

I've just had the front up on axle stands and found exactly as Den says.

The handbrake lever on the left calliper had seized.

I stripped it all and cleaned it. WD40 and grease and it's free again. I checked the right hand side and that was free so I greased it any way.

The handbrake cable sheath seemed ok. No splits as it goes through the ring supports but, the sheath had sort of snapped just as it approaches the bulk head at what looks like a joint. I squirted some oil into the sheath and taped it up with 3 layers of gaffer tape to keep the weather out (hopefully).

All seems to be working now.

I'll take another look in a couple of weeks to see if it's getting stiff again.

Thanks.

AndersDK · Post by **AndersDK** » 27 Dec 2008, 20:56

Just had exactly the same problem on a '02 Xsara HDI2.0.
But this was on the rear wheel.

Seems that the later style combination calipers (with integrated handbrakes) on Citroens have a tendency to run dry and then the mechanism sticks leaving a binding brake.

KevMayer · Post by **KevMayer** » 28 Dec 2008, 00:02

It looks like this could be something to look out for when changing brake pads.

I can't imagine what the arrangement is inside these callipers where the integral handbrake lever pushes the piston forward. Does it pressurize the fluid or physically act on the piston ? and also why does the piston have to be rotated to push it back ?

Has anyone got any drawings to show the arrangement ?

den169 · Post by **den169** » 28 Dec 2008, 10:43

The pistons in these calipers are on a thread,So have to be wound back when fitting new pads.

VertVega · Post by **VertVega** » 28 Dec 2008, 11:59

These pictures are from my Xantia's front right brakes. I have marked the hand brake lever protective rubber cap. You can open this cap and turn upwards. Clean the spring mechanism and apply grease to it. In mine it is fixed with a cable tier.

In this second picture you can see why you have to turn the brake piston to get it in. It is taken during the seals replacement operation.

Hope these will be helpful

AndersDK · Post by **AndersDK** » 28 Dec 2008, 12:57

From VV's pictures its easy to recognise the threaded rod operating the piston. In the bore from where the threaded rod protrudes is a small O-ring seal which is located in a tapered recess. This makes a positve seal against the highest available pressure in the caliper.
Its not here problems arises. Its on the outside under the rubebr protector cap, where the rod pivots in external bushings or bores.
The rod runs dry out here over time and will need a good work over with grease.
Its not necessary to use special heat resistant grease, as the heat is always consumed by the disc, not the caliper body and piston.
You can use any suitable CV-joint grease, alu-paste or whatever you have in your service tool box.
Its important however, to ensure the grease is worked into the rod & bores.
May help using a drop of engine oil.

JohnD · Post by **JohnD** » 28 Dec 2008, 19:30

Note also that when retracting the pistons on a C5 the offside need to be wound anticlockwise and the nearside clockwise.