Bloody Audi calipers!

[Audiden]

My project 90 failed it's MOT today on the n/s/r parking brake recording little or no effort.

This caliper replaced the siezed original & only last week was bled, a replacement return spring & bolt fitted as I sheared the previous bolt in the caliper fitting it up some time back. Therefore the handbrake had not been used whilst the car had been laid up & whilst this bolt was missing... though I did once accidently apply the brake during this time which will have pulled the lever beyond it's normal travel

Thinking it might be an adjustment, once home I whipped the wheel off to find the handbrake cable tensions up as it should when the handbrake is applied, the previously lubed handbrake lever moves freely enough & everything else looks present & correct. But the handbrake has zero effect on applying braking to the n/s/r, absolutely nothing

The foot brake appears otherwise fine.

Anyone know why?

[saint001]

check your cables ,they may have seized ,if so best bet is to replace .have you stripped down the calliper if not do so and use lashings of copper grease.always works for me lol

[rich.r]

could it br the bit that actuates the piston in the caliper when you pull the handbrake on

[Phil Payne]

Fitting rear calipers so that the handbrake works is not intuitive:

http://www.isham-research.co.uk/quattro/caliper.html

[BIGGYIN]

I was going to say,what is in Phil's link.Wind back pistons,fully.

[Audiden]

Originally Posted by rich.r

could it br the bit that actuates the piston in the caliper when you pull the handbrake on

That what I wondered...

I'll wind back back the piston, change the pads for new ones as the current ones are 50% worn & adjust the cables & see how that goes.

The isham-research article is as helpful as ever, but seems a lot of trouble to go for on my tatty old Audi lol!

[Ben]

I had similar B4 trouble after cleaning and reseting umpteen times, I followed a suggestion on another forum to drive around with the handbrake on when possible to get them hot, not glowing but smelly. I did this, mostly when going down hills and a few days later I could get both wheels to lockup in the dry.

I think it was something to do with wearing off a glaze that builds up due to the rears not doing much in normal use.

Edit: Found the forum post: http://www.audifans.net/ftopict-18572-.html

[gabriel.oconnell]

had this with my quattro m8 had to rel place both calipers and brake lines discs and cables too

[Audiden]

Originally Posted by gabriel.oconnell

had this with my quattro m8 had to rel place both calipers and brake lines discs and cables too

Hmm, not what I want hear...

I'll go down the cheap fix road first & see where that takes me

Bloody Audi calipers

[Audiden]

Originally Posted by rich.r

could it br the bit that actuates the piston in the caliper when you pull the handbrake on

Tell me more about this bit

I wound back the piston in to the n/s/r caliper tonight, re-bled same, replaced the pads with slightly roughened up new ones, adjusted up the handbrake cables & apart from the o/s holding very well now, there is ZERO improvement on the n/s.

The n/s/r wheel spins freely with the handbrake fully applied???