NS Front Brake Not Working - ABS Issue?

[Tractor Dave]

It’s for the ABY. Do you know if the brake accumulators are still available? Also is it a similar test to what you do on a UR?

Yes, you can still get new ones. Also possible to re gas old ones if the membrane is good. It's a specialist job mind as you need to drill a hole and fit a valve.
I think the test is the same.
However, brake bomb will have nothing to do with no fluid at one caliper.

[steverrquattro]

There used to be a place you could send the pump to for repair. I've never looked inside one. Which car is this for? I have a spare aby pump here.
The warning is likely the bomb not holding pressure.

It’s for the ABY. Do you know if the brake accumulators are still available? Also is it a similar test to what you do on a UR?

[Tractor Dave]

These guys used to have a good reputation. I've never tried them though.
https://www.ecutesting.com/categorie...iAAEgLTDfD_BwE

[Tractor Dave]

There used to be a place you could send the pump to for repair. I've never looked inside one. Which car is this for? I have a spare aby pump here.
The warning is likely the bomb not holding pressure.

[steverrquattro]

Haven’t used the car for three weeks and the NS calliper is back to not working and no fluid coming out as before. Are there any filters in the ABS unit that can be cleaned out?

Also when I first started the car this time and pressed the brake pedal with force, the brake warning signal appeared on the dashboard. Could this have any relevance on the fault?

[AndyP]

Be careful ordering from Autodoc, their parts cross referencing system is crap and you'll inevitably get the wrong kit! I get all mine from Biggred.

https://www.biggred.co.uk/audi-coupe-b3-89-8b3-2226-1990-1992-petrol-engine-vehicle-1373/catalogue/brk-caliper-repair-kits

[sal_s2]

AndyP has rebuilt quite a few sets of brakes for people

[newsh]

Absolutely brilliant that and very much appreciated. Also thanks to Tractor Dave for the offer of the spare ABS unit.

Rebuilding the brakes is a job I've never done as it's always been a case of not having the time resulting in an emergency exchange at GSF. However I fancy doing these myself and save a bit of cash as well.

We did the front calipers on my lad's Skoda recently, we were fitting new pads and pistons were quite hard to push in. I looked under the dust seals and could see rust.
Got pistons and seals from Autodoc, not expensive and the job went well and he now has excellent brakes.

[Tractor Dave]

Not too difficult and very rewarding. Send me a pm if you get stuck. I've done quite a few now. I would recommend getting a kit with new pistons.

[steverrquattro]

Sometimes you have to take service history with a pinch of salt! One of my neighbours always has his car serviced every year, but refuses to have any fluids changed other than oil, his car is on an 07 plate he has had the car since new. He's thinking of selling it and claiming it's got full service history

Think I got my kits from autodoc, but you can get them from ebay as well

Front
D41719C AUTOFREN SEINSA Repair Kit, brake caliper Front Axle ➤ AUTODOC
Rear
D4845C AUTOFREN SEINSA Repair Kit, brake caliper Rear Axle ➤ AUTODOC

Absolutely brilliant that and very much appreciated. Also thanks to Tractor Dave for the offer of the spare ABS unit.

Rebuilding the brakes is a job I've never done as it's always been a case of not having the time resulting in an emergency exchange at GSF. However I fancy doing these myself and save a bit of cash as well.

[Tractor Dave]

Agree. Those brakes need an overhaul.

[B5NUT]

Sometimes you have to take service history with a pinch of salt! One of my neighbours always has his car serviced every year, but refuses to have any fluids changed other than oil, his car is on an 07 plate he has had the car since new. He's thinking of selling it and claiming it's got full service history

Think I got my kits from autodoc, but you can get them from ebay as well

Front
D41719C AUTOFREN SEINSA Repair Kit, brake caliper Front Axle ➤ AUTODOC
Rear
D4845C AUTOFREN SEINSA Repair Kit, brake caliper Rear Axle ➤ AUTODOC

[steverrquattro]

That fluid looks well passed it's best. I would also look at a rebuild kit for the callipers. My guess rust has got on the piston and that's what is causing it to stick. I would also look a rebuilding the rear at the same time.

It’s got the best service history of any car I’ve ever seen but that brake fluid is rank. Where do you get your rebuild kits from?

[B5NUT]

That fluid looks well passed it's best. I would also look at a rebuild kit for the callipers. My guess rust has got on the piston and that's what is causing it to stick. I would also look a rebuilding the rear at the same time.

[steverrquattro]

First of all I gave the block on top of the ABS unit several taps with the mallet as I’d read this on another thread. I then tried pressure bleeding and when I opened the bleed nipple nothing came out but it did dribble out from around the threads. The bleed nipple was then removed and found to be blocked. When installed back in I was finally able to bleed the brake.

However when road tested the calliper on the NS was still not engaging. So it was removed once more from the carrier and the brake pedal applied. This time the piston came out but just one whereas I expected them both to come out? It was then pushed back in and the pedal applied again and the other one came out. Pushed it back in and then road tested and now working.

All I will say at the moment is that the fluid looks dirty and I’ll do another test drive tomorrow to see if it’s still working.