Binding rear brakes - not calipers

[Sandspider]

Hi all

As above. My 944 Lux has binding rear brakes, but it doesn't seem to be the calipers. They move freely (and were stripped down and lubed last year), but once the brakes are applied they don't seem to pop back from the discs as they should. I'm thinking this could be related to an internally collapsed brake hose? Do 944s have one way valves or anything on the rear brakes?
Basically, other than the calipers, what's the next most likely cause of binding brakes? Would be nice to have some ideas of what to look at next.

Thank you.

 

[blade7]

Hand brake?

 

[Sandspider]

Ah, no - forgot to say, handbrake is fine too. Engages and disengages as it should.

 

[richardjjs1]

I wonder if its worth doing a brake fluid flush. Have a look at what is coming out.
Presume the pads are not sticking

 

[Sandspider]

The pads are free.

Brake fluid looks ok in the header tank, but hasn't been changed for a few years. That could be it...

 

[chaser]

I think you are right/on the right track with collapsed brake hoses, had exactly the same issue on an old VW I had.

 

[BlackMagic]

I think that the most likely problem is the seals (dust or fluid) that seal the brake pistons (or possibly corrosion on the pistons) meaning that they don't spring back that small amount that provides the clearance.

IMHO a collapsed hose wouldn't stop the fluid flowing back to the master cylinder.

William

 

[richardjjs1]

If the pistons move freely I would have though they are OK
Beside you said they where cleaned recently



Did have a BMW Convertible 2009 with54k that needed a new calipre - but apparently wasn't driven for best part of a year (FRom MOT). Piston pushed back OK ( But, of course, under pressure) but still stuck. Garage provided new Calliper and F1 fitted it under warranty)

I don't think a new seal set is that much -

Richard

 

[Ivan Ford]

I had a similar problem with a Jaguar, it was the flexible hoses breaking down. It was a fairly easy job to change the hoses and bleed the brakes.

 

[Sandspider]

Thanks for the suggestions one and all.

Pistons move freely, and were stripped, cleaned up etc. last year, so don't think it's them.

Will have the car recovered to my usual garage and let him look at it.

There are various other bits that need looking at too (fuel lines, brake lines, fuel tank, sills, steering, belts and rollers...) - could be an expensive year for the 944, or time for some tough choices!