Rear brake pipe

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elma
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Rear brake pipe

Post by elma »

Changing rear brakes today on xantia and I've come across a new problem I havent had before. After unscrewing the pipe from the caliper the little screw thing will slide up the pipe but the pipe won't leave the caliper. Don't want to force it so I split caliper and cleaned one half in situ and other half in a bowl.
Its weird though, do you think it was just stiff or did I miss something. The brake wasn't biting before I stripped it, could it have been full of air and so the pipe is stuck? Maybe by the next pair of pads it will act normal.
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Mandrake
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Post by Mandrake »

Yep, I've had that happen to me before, usually in places with little access - the pipes can get really stuck in the hole sometimes.

Basically what you have to do is grasp it in a way that you can pull it directly out, and at the same time wiggle it from side to side without bending the pipe. Don't twist it.

Sometimes it will seem like it will never come out but after enough wiggling it will suddenly let go.

Regards,
Simon
Simon

1997 Xantia S1 3.0 V6 Auto Exclusive in Silex Grey
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2011 Peugeot Ion Full Electric in Silver
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AndersDK
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Post by AndersDK »

It is in fact normal to find the pipe end sticking in its component.
Careful wriggle the component back and forth while applying hand pressure to remove the pipe.

Patience will do it - sooner or later.

With the caliper in halves - TAKE NOTE of the dished seal that fits between the halves. If you miss it - you will have a green mess all over from the rear brakes.

While at the job : clean the mating faces on the inner caliper half and the rear arm. Then smear both with a heavy grease or rust protector.

Note that the rear brakes pressure originates from the rear suspension pressure. With rear arms dangling you get no pressure against the suspension and thus you will get NO pressure to the rear brakes.

If you set the suspension to the highest position, you bypass the automatic height regulation and forces maximum system pressure out to the suspension. This in turn also forces maximum system pressure feed for the rear brakes circuit - no matter the rear arms are dangling or they are loaded with the weight of the car. Of course no pressure is fed to the brakes until you press the pedal.

Air in the brake lines will NOT cause lack of brake pressure. Because when you press and hold the brake pedal, pressure to the brakes are build up in the doseur valve, until pressure equilibrum is reached according to the pedal position. This means that any air will simply be compressed until the required pressure is reached.

However - the air takes quite some time to compress. This is clearly felt as an odd delay in brake force from pedal pressed until car starts braking.
Result is therefore you most often will overbrake, as the natural counter-acting is to press further on the pedal, because of the hairy feeling down your back .... :shock:
Anders (DK) - '90 BX16Image
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