A7 Brake failure

[+robster+a7+tdi]

Anyone had this? see pics

Anyway could have been worse , happened holding the brakes in car park 3 miles from house so managed to tickle it home with caution.

Looked at it this morning and it seems the n/s rear cv ( and or boot) has rubbed through the flexi hose and sprung me a massive leak with loss of brake pressure .

To my knowledge nothing has been changed down here except the ebc discs and pads which require caliper and bracket removal but the hose position has never been changed and there are no missing brackets.

Car is on original s line suspension.

Worth a look for owners to reach down behind caliper and feel under hose for signs of rub through at drive shaft, if DIY or at least ask garage to check it next time its in for something as its easily missed ( my car passed mot last month (120 miles ago).

So im off to look for 2 rear hoses and its a good opportunity ( snide time of year) to change the brake fluid

I will update a better pic when stripped as im as well leaving as is for now until i get the new hoses.

 

[Bishop187]

Anyone had this? see pics

Anyway could have been worse , happened holding the brakes in car park 3 miles from house so managed to tickle it home with caution.

Looked at it this morning and it seems the n/s rear cv ( and or boot) has rubbed through the flexi hose and sprung me a massive leak with loss of brake pressure .

To my knowledge nothing has been changed down here except the ebc discs and pads which require caliper and bracket removal but the hose position has never been changed and there are no missing brackets.

Car is on original s line suspension.

Worth a look for owners to reach down behind caliper and feel under hose for signs of rub through at drive shaft, if DIY or at least ask garage to check it next time its in for something as its easily missed ( my car passed mot last month (120 miles ago).

So im off to look for 2 rear hoses and its a good opportunity ( snide time of year) to change the brake fluid

I will update a better pic when stripped as im as well leaving as is for now until i get the new hoses.

Holys#!+ gald your ok


Sent from my iPhone using Tapatalk

 

[Sandra]

@+robster+a7+tdi glad that your ok, that must of been scary as. Try our parts request for hoses. Members get a discount

https://www.audi-sport.net/xf/support-tickets/open

 

[+robster+a7+tdi]

thanks but im going to order a HEL braided hose kit and do the lot, just need to pick a colour lol
https://www.vagbremtechnic.com/hel-...udi-a7-all-models-exc-rs7-2010-on-4-line-kit/

 

[+robster+a7+tdi]

Decided to go back out and brave the cold and make sure I don't need to order a cv boot .
Its ok the flexi has been riding mostly on the metal band clamp by the look of things.

Anyway i flipped the hose up on itself to see the damage.
note there is a thicker "protective" sheath at this position so the wear may look a bit dramatic before it actualy got to the actual hose itself , if you know what i mean.

 

[+robster+a7+tdi]

Update
Hoses arrived Saturday evening but was busy with other things.
Started this evening ( Sunday) and only replaced back hoses - will do fronts next weekend
changing hoses was the easy part
only 17mm socket to remove wheel and only 2 spanners reqd 14mm (short) + 11mm.

Change one hose and bleed that line was my logic

Bleeding was a pain - maybey because i left car for a few days and it caused air too far up line to abs module?

But scanned abs module to try a few things out and brake bleed stage1 was the only function that helped electrically pump through the fluid ok

But im left with an abs / trc fault indication i cant clear yet because during tinkering in the settings with my obd eleven i have initiated a system function test which can not be cancelled but rather only taken on a drive and set some prerequisites to check and finalise the system test.

Anyway looked at steps involved and watched youtube video and tried going out to do said system test requirements but the part where you drive at 13mph with steering ( left or right) at between 90 and 180 degrees to check the yaw sensor proved very difficult because all the big carparks are pretty full of Christmas panic buyers today and never got it completed.

will do the fronts next weekend and try think of a derelict big open space in an industrial estate or something to do the test

heres some pics of my day



3 small things to note
1...I said n/s hose failure when in fact it was offside failure
2...The failed hose natural bend was a mirror image of opposite side ( should have arched upwards away from driveshaft) according to the good side.
3.. on fitting new flexis at brake pipe / bracket end, i had to open up spring clip arms to stop any rattle / play left by the small difference on longer length of new fittings

 

[+robster+a7+tdi]

OK we can call it a wrap !
went out Sat morning and changed the front flexis
jumped out to local motor factors in my van and got some more new brake fluid.
Cleaned up my power bleeder and related items.

Was expecting a bit of a time bleeding it on my own but it went rather smoothly, i went full offensive on it with pressure from power bleeder , one way valve at caliper , engine running and pump pedal quite fast then run out and lock up bleeder after about 20 pedal pumps each corner.

Bled and flushed through and pic shows the not so clear fluid i have flushed out vs what is in my one way valve line.

managed to go out and do the system test drive in my local industrial estate and cleared the trc / abs lights first attempt.

As this is my weekend run around may be placebo effect due to driving van all week but brake pedal is sharp and responsive so im happy with the effort .