RESOLVED 👍 Need to fit new brake pipes from ABS unit to front wheels...

[gsmdo]

Hi there,

I had new front calipers fitted to my 2006 B7 Convertible 2.0 140 diesel last summer. Whilst the work was being done, I asked the tech to fit a pair of new HEL flexible hoses (I did the same thing when having the rear calipers replaced a couple of years back).

Unfortunately, the tech was unable to undo the hoses at the 'car' end, although they came out of the calipers OK, and so the job was kind of half done.

Normally this wouldn't be a problem - you'd cut the brake pipe off a cm or so from the end of the copper pipe, reflare, and fit a new joint.

Except this model of Audi uses a different material - an aluminium alloy(?), which can't be dealt with in this way. I forget the details, but apparently the pipe can't be cut and reflared.

The good news is that my brake hoses seem to be in good order, but obviously there will be a time somewhere down the line where this isn't the case, and this is a car I intend to keep for a while.

So - can anyone suggest a work-around for this please?

My solution would be to replace the two pieces of pipe running from the hose to their destination on the car (I'm assuming the ABS unit) with copper brake pipe, but the tech blanched at this, saying that the pipe run was buried deep in th engine bay and would require a lot of dissassembly (and therefore charged hours). I will confess I haven't looked at the pipe run to confirm this - although the tech is a reliable chap and I'm happy to take his word on this.

Any help and advice appreciated.

Thanks,

Mike

 

[Stevey Y]

1 hour ago, gsmdo said:

Hi there,

I had new front calipers fitted to my 2006 B7 Convertible 2.0 140 diesel last summer. Whilst the work was being done, I asked the tech to fit a pair of new HEL flexible hoses (I did the same thing when having the rear calipers replaced a couple of years back).

Unfortunately, the tech was unable to undo the hoses at the 'car' end, although they came out of the calipers OK, and so the job was kind of half done.

Normally this wouldn't be a problem - you'd cut the brake pipe off a cm or so from the end of the copper pipe, reflare, and fit a new joint.

Except this model of Audi uses a different material - an aluminium alloy(?), which can't be dealt with in this way. I forget the details, but apparently the pipe can't be cut and reflared.

The good news is that my brake hoses seem to be in good order, but obviously there will be a time somewhere down the line where this isn't the case, and this is a car I intend to keep for a while.

So - can anyone suggest a work-around for this please?

My solution would be to replace the two pieces of pipe running from the hose to their destination on the car (I'm assuming the ABS unit) with copper brake pipe, but the tech blanched at this, saying that the pipe run was buried deep in th engine bay and would require a lot of dissassembly (and therefore charged hours). I will confess I haven't looked at the pipe run to confirm this - although the tech is a reliable chap and I'm happy to take his word on this.

Any help and advice appreciated.

Thanks,

Mike

 

Hi personally I would leave well alone until they actually need replacing then you can get nasty with the flexable/metal pipe connection and have a go at it with some heat and a lot of plusgas it will come free eventually you just have to be patient and careful.

Steve.

[gsmdo]

21 minutes ago, Stevey Y said:

Hi personally I would leave well alone until they actually need replacing then you can get nasty with the flexable/metal pipe connection and have a go at it with some heat and a lot of plusgas it will come free eventually you just have to be patient and careful.

Steve.

Hi Steve,

That would require my schedule being set by the fault, not by me 😄

I'd rather address it at a time convenient to me. That way I can then still try the traditional methods - to destruction if necessary - as you suggest, but have immediate access to Plan B (whatever that might be) to minmise the time  the car is off the road...

Mike 👍

[Stevey Y]

38 minutes ago, gsmdo said:

Hi Steve,

That would require my schedule being set by the fault, not by me 😄

I'd rather address it at a time convenient to me. That way I can then still try the traditional methods - to destruction if necessary - as you suggest, but have immediate access to Plan B (whatever that might be) to minmise the time  the car is off the road...

Mike 👍

Hi I have run all of my cabs on a preemptive maintenance schedule and covered over 900,000 miles and never had to change a rubber brake hose on the fronts, or a metal brake pipe for that matter Fords used alloy brake pipes and there lies the problem [bi metal corrosion] in fact the last car went to its new owner with over 270k on the clock, the thing that causes most problems with any brake pipe is lack of timely fluid changes as its the water in the fluid that is the catalyst for premature corrosion, apart from which to get the correct length and shape for a copper replacement you will have to present the original as a pattern and pray the people who do it have the correct kit to follow that pattern bending and angle tools, it is nowhere as simple as it looks and if you manage to kink the copper pipe its game over.

Steve.

[Magnet]

Hello Mike,

Preventive maintenance is great if (in caps) any such maintenance is seen as necessary in the foreseeable future. You mention brake pipes which are difficult to get at, leave alone change, so why not extend your ‘maintenance’ and invest in a thorough assessment of the condition of these pipes to see if there indeed any significant deterioration in their condition. If there isn’t, just forget it, and find something else to worry about. If there is any concern, then consider the degree of concern vs. the complexity of change, and form a decision from there. 
Kind regards,

Gareth. 

[gsmdo]

On 4/6/2022 at 9:18 AM, Magnet said:

Hello Mike,

Preventive maintenance is great if (in caps) any such maintenance is seen as necessary in the foreseeable future. You mention brake pipes which are difficult to get at, leave alone change, so why not extend your ‘maintenance’ and invest in a thorough assessment of the condition of these pipes to see if there indeed any significant deterioration in their condition. If there isn’t, just forget it, and find something else to worry about. If there is any concern, then consider the degree of concern vs. the complexity of change, and form a decision from there. 
Kind regards,

Gareth. 

It's not the pipes that will be the likely point of failure Gareth, but the hoses. The reason I want to replace the pipes is that they are seized to the OEM hoses and cannot be cut and reflared like a copper brake pipe.

It is inevitable that rubber hoses will eventually degrade with age - or just fail by a flint being kicked up on an unlucky trajectory. If that happens when I'm miles away from home - on the continent for example, this could be a major problem.

I'm not being Chicken Little here, just trying to have more of a plan than 'trust to luck' to deal with this, that's all.

Cheers,
Mike

 

[Magnet]

OK Mike. I can now better interpret your concern, and the consequence of renewing the flexible hoses - which will result in the ends of the metal brake pipes being ‘destroyed’ by trying to separate the two. 
Not meaning to cause offence, but it’s clear to me that you are not going to rest easy until you have renewed these serviceable hoses, so really, the general opinion of the forum is not what you want to hear - and that’s OK too. 

I fear it’s not going to be any consolation to your way of thinking, but in 60 years of motoring, I’ve never experienced an unexpected and catastrophic failure of what appears to be a serviceable brake hose, following normal inspection at service intervals, but I might have been lucky -? You say, these could fail at some point, even when abroad, but why not be positive, and think they won’t - following your normal inspection. Sods Law will point to component  B subsequently failing when you are worrying about the potential of component A failing! 

Again, with my negative hat on now, this could turn into one of those jobs where you wished you had left well alone! I really hope it doesn’t, but… 

Apologies Mike, but I don’t feel I can offer any more meaningful advice with this. 
Kind regards,

Gareth.

p.s. If you are minded to still go ahead with this - and I’m sure you are - is it worth getting a fine intense heat source and heating the hose to pipe connection in the hope that may help free the two from one another? Nothing lost if you still have to replace the metal pipe as well as the flexible. 
 

[Stevey Y]

1 hour ago, Magnet said:

OK Mike. I can now better interpret your concern, and the consequence of renewing the flexible hoses - which will result in the ends of the metal brake pipes being ‘destroyed’ by trying to separate the two. 
Not meaning to cause offence, but it’s clear to me that you are not going to rest easy until you have renewed these serviceable hoses, so really, the general opinion of the forum is not what you want to hear - and that’s OK too. 

I fear it’s not going to be any consolation to your way of thinking, but in 60 years of motoring, I’ve never experienced an unexpected and catastrophic failure of what appears to be a serviceable brake hose, following normal inspection at service intervals, but I might have been lucky -? You say, these could fail at some point, even when abroad, but why not be positive, and think they won’t - following your normal inspection. Sods Law will point to component  B subsequently failing when you are worrying about the potential of component A failing! 

Again, with my negative hat on now, this could turn into one of those jobs where you wished you had left well alone! I really hope it doesn’t, but… 

Apologies Mike, but I don’t feel I can offer any more meaningful advice with this. 
Kind regards,

Gareth.

p.s. If you are minded to still go ahead with this - and I’m sure you are - is it worth getting a fine intense heat source and heating the hose to pipe connection in the hope that may help free the two from one another? Nothing lost if you still have to replace the metal pipe as well as the flexible. 
 

Hi, was recently given the job of putting new callipers on my mates twenty two year old Renault Kangoo van the rubber hoses were the original ones and showed no sign of wear or abrasion so left them as is, the van has done 170k and has always had the brake fluid changed regularly which reinforces my point about corrosion from within, as for breaching the outer/inner rubber I have never seen that in my lifetime as most hoses are double sleeved with a nylon braiding between the two skins and if you look at it logically a random piece of flint would have to do the same amount of damage to a new hose as an old one, I have seen braided hoses fail as the centre rubber rots out underneath the braiding but being as there is no manufacturer based standard for these they don't really apply and most people fit these for aesthetic purposes, this type of hose falls down on the fact they have no expansion capacity under heavy braking and definitely nowhere near the stretch capacity of an ordinary hose.

Steve.

[gsmdo]

I just thought I'd pop a solution post in here.

As some of you may have read, I had the dual-mass flywheel and clutch replaced on the A4 this week. Since the old girl was going to have her insides hanging out, I discussed whether this might be an opportunity to replace the brake lines (to the front wheels). They agreed it would be very much easier to do with the car apart, so I had new cupro-nickel (reflareable) brake pipes fitted - and my braided HEL hoses fitted to the front calipers.

Oh - and a fluid change for the clutch (natch) and the brakes.

My paranoia is thus satisfied... 😆