Steel brake line replacement

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Julie Z3
Joined: Mon 22 Nov, 2010 09:47
Posts: 216

  Z3 roadster 2.8
Location: Bristol

Steel brake line replacement

Post by Julie Z3 » Thu 30 Oct, 2014 18:53

Did the usual search without success so hope I won't offend anyone if this has been done too death! Had an mot last week and one of the advisories was new front and rear steel brake pipes, has anyone here had to replace theirs, and if so what are the best options?
Genuine BMW, one of the suppliers on ebay who sell pre-made lines to order or buy a roll of pipe (what would be recommended) and a decent flaring tool and have a go myself. The front and rear pipes just after the flexi pipes look fairly straightforward but the pipe after the flexi over the rear diff appears to go under the fuel tank and looks like a major bit of diy, any advice appreciated, julie

Del
Joined: Sat 19 Nov, 2011 18:35
Posts: 2115

  Z3 roadster 1.9

Re: Steel brake line replacement

Post by Del » Thu 30 Oct, 2014 19:28

Sometimes some of these "advisory" items can be overly picky/fussy. In September 2012 my Z3 had an MOT and like you I had an advisory that the brake pipes to and from the rear, nearside wheel were showing signs of rust. In early 2013 we were underneath the car to remove/refurbish the ARB and drop-links and I decided to focus on the rear brake pipes. Firstly, I was struggling to find much rust but nonetheless I cleaned all the rear pipes, up to the fuel filter/belly plate. I cleaned with a scotch pad and wiped on Fertan rust killer followed by a thorough coating of clear Waxoyl. The car has since passed two MOTs in 2013 and 2014 with no mention of this whatsoever despite taking the car to a garage renowned for "not taking any prisoners". :)

The Z3s may well differ underneath as I can't recall a section running under the fuel tank on my 1.9.

roadvoyager1
Joined: Sun 19 Jan, 2014 18:30
Posts: 65

  Z3 roadster 2.8

Re: Steel brake line replacement

Post by roadvoyager1 » Thu 30 Oct, 2014 20:33

If you are intending to keep the car I would suggest you investigate replacing the steel pipes with copper. I am lucky that mine was done before I bought it. Copper will deteriorate with time but last longer than steel. The bulk of the cost (or effort if you do it yourself) will be in the labour. I know others have changed to copper and may be able to tell you more about the costs.

t-tony
Joined: Sun 21 Feb, 2010 23:17
Posts: 352

  Z3 roadster 2.0
Location: torksey lock

Re: Steel brake line replacement

Post by t-tony » Mon 03 Nov, 2014 16:17

Regarding brake pipe replacement, copper will far out last steel pipes but they are very difficult to re-use. By that I mean when you try to loosen the steel union on a copper pipe it will twist the copper pipe very easily and ruin it. A better alternative is the older cupro- nickel type of pipe, more difficult to bend (especially tighter bends) but more user friendly. Re the pipes over the tank, easiest thing to do is remove the tanks straps and allow it to settle on the exhaust or whatever, it can't come right down. Then you can pull it down at either side for access to change the pipes. It's not as hard as it looks.

Tony.
"Knowledge and experience are not always the same"

Julie Z3
Joined: Mon 22 Nov, 2010 09:47
Posts: 216

  Z3 roadster 2.8
Location: Bristol

Re: Steel brake line replacement

Post by Julie Z3 » Tue 04 Nov, 2014 13:52

Thanks for the information guys.........still undecided which way to go yet, will let you know the outcome when I do!

Julie Z3
Joined: Mon 22 Nov, 2010 09:47
Posts: 216

  Z3 roadster 2.8
Location: Bristol

Re: Steel brake line replacement

Post by Julie Z3 » Mon 10 Nov, 2014 17:04

Sorry to keep on guys but have decided to replace with new flexible hoses and Kunifer brake pipe, have purchased a decent flaring tool and a roll of pipe to go on with, does anyone who has done this job before know what the male and female brake pipe connections are , ie M10, long /short etc, as I don't want to have the wrong ones once the jobs started !

t-tony
Joined: Sun 21 Feb, 2010 23:17
Posts: 352

  Z3 roadster 2.0
Location: torksey lock

Re: Steel brake line replacement

Post by t-tony » Mon 10 Nov, 2014 20:11

These are standard 10mm male and female unions as fitted on millions of cars. If you can, remove one of each and take them to the factors as a pattern, or if that's not an option I can email some pictures if you want to pm your email to me. Before you make a start try a few practice " flares" to make sure you have it right first time. :)

Tony.
"Knowledge and experience are not always the same"

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pingu
Joined: Fri 30 Apr, 2004 17:01
Posts: 3337

  M roadster S50

Re: Steel brake line replacement

Post by pingu » Tue 11 Nov, 2014 14:48

My 330 failed last year's MOT for rear brake pipes. I bought a new (steel) pipe from BMW (<£10 iirc), but I couldn't undo the connections beside the clutch. I put it in a mate's garage and he couldn't undo it even on a ramp. He cut the pipe and tried to join the new pipe to the old pipe. He could flare the old pipe, but not the new one, so he used new copper pipe to replace the rusty section.

So, beware, steel pipe can be VERY hard to flare.
Pingu

Julie Z3
Joined: Mon 22 Nov, 2010 09:47
Posts: 216

  Z3 roadster 2.8
Location: Bristol

Re: Steel brake line replacement

Post by Julie Z3 » Tue 11 Nov, 2014 16:47

Thanks for the info guys...........after a little research here and other sites the kunifer seems to be the best option for diy replacements, that's why I wanted to know what fittings before I started as I had a quick go at the front hard lines to flexibles and they just seemed like they would break even with the proper flared spanner! Will get some 10mm fittings ordered, thanks again.

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