The usual Hard brake pedal, seized binding NSF brake - Culprits please?

[mebedforduk]

Morning all

The Mrs's A6 1.9TDI 99vintage 150K

We have the hard pedal, seized and smoking hot NSF

Plenum is dry as I removed the bung two yeras ago after it buggered the indicators and soaked the carpets

In the last three weeks

Brake booster - replaced ( no rust on show)
Blake lines - replaced
NSF calliper - stripped and cleaned

What do I spend my £££ on next?

All the hoses from the brake boost including the small vacuum hoses?
Or Master cylinder?
Or calliper

Im just wondering if anyone has ever got to the bottom of this problem and there is a one fix cures all


Its my fault as I was complimenting her car on being so reliable. Unlike my 245K A62.5tdi

Ta in advance

Mark

[Crasher]

When I have had this it has only been the servo full of rust when we replace the M/C anyway so that would seem a good place to start.

[mebedforduk]

Thanks Crasher

I will get the moths out of the wallet

Cheers

Mark

[mumutley]

Hi is it just the NSF sticking on?

Undo the join between metal brake pipe and flexi brake pipe a few turns get some one to press the brake pedal, you should get a reasonable gush of brake fluid, tighten this back up. undo flexi brake pipe to brake caliper (does the wheel turn free?) if so get some one to press the brake pedal, does brake fluid gush out? If yes tighten back up, press brake pedal a few times then try and turn wheel, does it turn if the wheel does not turn, brake stuck on change flexi brake pipe

[Crasher]

Blake lines - replaced

We are assuming he has already replaced the hose by his first post.

[zollaf]

presumption is the mother of all .......................

[Crasher]

**** up's...

[mebedforduk]

In this instance, presume would be correct

As Im up to my armpits with work at the moment I committed the godly sin of paying someone to work on one of our cars

Hes a VW main dealer mechanic who erm, fettles cars outside of work to gain erm experiance and as a hobby to keep him away from the wife.

Flexi replaced plus steel pipe full length as it was rusted into the flexi connector

Ive been looking at the tangle of vacuum hoses tonight but athough they look a bit frayed there is no hissing when the brakes are being pumped even if I tug them about

Mechanic Matt is going to ask in the workshop in the morning but his first diagnosis was sticky calliper or servo, but of which are now ruled out. He did suggest petrol and a match though....................

Now the beemer bike has sprung an oil leak

Ta all for the replies

[mumutley]

Hi all OK I will try not to Presume!!

The N/S/F is the only caliper sticking on? After all above work carried out.
Jack car up all four wheels off the ground.
Go back to basics (I know you say certain items have been done but do they work correctly?)
Remove N/S/F wheel, ensure wheel turns free, push pads back in caliper Does the piston move freely?
Move caliper on slides does caliper move free on slides?
N/S/F wheel spins OK?
Clamp flexi brake hose (for N/S/F) apply brake on off several times; check all other wheels spin free OK?
Remove clamp from flexi pipe, apply brake on off several times N/S/F wheel stuck? Or OK.
If sticking I would then go with crasher change master cylinder. Is there a brake balance valve for the N/SF? Only other item is ABS pump.

[mebedforduk]

[QUOTE=mumutley;732894]Hi all OK I will try not to Presume!!

Fantastic and simple idea

I will try it at the weekend, or if it ever stops raining

The Missis gingerly took it out today and it didnt start playing up until she got to her 3 mile away destination.

We live in the sticks are seeing two cars at the same time is considered rush hour so she was steady with the handbrake at the ready

Did you know that unmade roads and Audi suspenion legs dont go well together?

And to think she convinced me away from Citroen XMs to get away from having to fix em all the time.

I prefer problems where they either work or dont work

Thank you again