Rear brake line dilemma

[iiNNeX]

Hey guys,

It has come to my attention that I need to replace the rear brake pipe/hose combos that connect to the rear calipers as they are corroding and have been on the last 2 MOTs as advisory items. I believe they come in 2 sections as you can see in this diagram:


The item I need to replace is number 5 and it costs around £55-£60 from BMW. You can get them from Bosch for about £22 which is better but I thought to myself if I am going to pay that sort of money, I might as well change them all around for braided lines and some better fluid more suited to fast road driving.

The problem with braided lines is I have only seen one other thread where some does HEL braided lines to an E85 and he had some hiccups: https://z4-forum.com/forum/viewtopic.php?t=107044

So the question is, do I go for OEM replacements of the corroded items only, Bosch replacements to save cost or do I go the full hog with braided lines all around from the likes of HEL and hope I don't have any fitting issues? I am overhauling the whole braking system with new discs, pads, sensors, fluid, calliper refurb ect so if there was a time to do it, this is probably it haha.

Thanks

 

[colb]

Put braided stainless HEL hoses all round on my 2.5 not long ago. I had an advisory in September rear nearside brake line corroded.
Paid around £80 for a full set of braided lines via ebay, you can buy a single hose for the rears so you don't have the twin hoses outer and inner but then you will need to make up a support in addition to the stock support for the hoses. I kept to the twin hose setup so they were routed in the stock hose supports. My hard lines cleaned up well with a light emery cloth rub down and were thren painted with black metal smootright paint. The ferrals on the old hoses were very corroded but they stripped out without too much trouble. You will find the hard lines can corrode where they emerge from the plastic cable channel under the car into the nearside wheel arch where the lines get all the wet and road debris flung onto them by the rear wheel. I was thinking of putting some split plastic conduit on the lines there to give them some more protection.
If you dont want HEL brand try these https://www.ebay.co.uk/itm/283460834564?fits=Car+Make%3ABMW%7CModel%3AZ4&hash=item41ff951504:g:xMAAAOxyVLNSwuEt

 

[iiNNeX]

Put braided stainless HEL hoses all round on my 2.5 not long ago. I had an advisory in September rear nearsiode brake line corroded.
Paid around £80 for a full set of braided lines via ebay, you can buy a single hose for the rears so you don't have the twin hoses outer and inner but then you will need to make up a support in addition to the stock support for the hoses. I kept to the twin hose setup so they were routed in the stock hose supports. My hard lines cleaned up well with a light emery cloth rub down and were thren painted with black metal smootright paint. The ferrals on the old hoses were very corroded but they stripped out without too much trouble. You will find the hard lines can corrode where they emerge from the plastic cable channel under the car into the nearside wheel arch where the lines get all the wet and road debris flung onto them by the rear wheel. I was thinking of putting some split plastic conduit on the lines there to give them some more protection.
If you dont want HEL brand try these https://www.ebay.co.uk/itm/283460834564?fits=Car+Make%3ABMW%7CModel%3AZ4&hash=item41ff951504:g:xMAAAOxyVLNSwuEt

Hey man, thanks for the detailed reply. So you are saying that whichever kit I buy (that comes with 6 hoses) it will still need to use the OEM metal connecting pipe at the rear? That sucks as that is the problem piece of me, which started this whole dilemma haha. Is it not possible to just buy the metal pipe from BMW?

As for braided line brand, I don't mind using HEL I have been using them and Goodridge for a few years on various cars, but it's just this car seems a tad more complicated than I thought it would be. Those Wezmoto ones look the business and cost quite a bit less, so perhaps I could take that route if I could replace the metal connector pipe.

I know you said you rubbed yours down but I have a feeling mine will be a little worse for wear for this to work, I ll give it a go before replacing though. Thank you for the input!

On another note, it seems that you can order a custom piece from HEL for the rear to be 1 long line and choose where you want mounting hardware etc.. but doing that is beyond me at this stage as I don't know what all the parameters need to be... I did find this which elaborates:
https://z4-forum.com/forum/viewtopic.php?t=106443

Apparently you can order standard front kit and rear to spec like this along with some circlips:


I might call HEL and have a chat to see my options.

 

[colb]

The stock outer hose has the short metal hard line on it, changing to braided hoses replaces that short length for a complete braided hose that joins the inner. You need to check the condition of the hard line from where it emerges from the underside plastic channel and routes to the top of the wheel arch where it connects to the inner hose. If the hard lines are too corroded then you can graft a replacement hard line in by cutting and making a joint inside the plastic channel underneath the car and route the new hard line to the wheel arch. The single long braided hose is an option worth considering, a cable tie would suffice as an extra mounting point to provde the extra support.

 

[Jakg]

I replaced the flexi+solid+flexi rear line with a single braided flexi because the unions on mine were shot.

I put the dimensions in the thread you've linked to and it worked fine.

 

[iiNNeX]

The stock outer hose has the short metal hard line on it, changing to braided hoses replaces that short length for a complete braided hose that joins the inner. You need to check the condition of the hard line from where it emerges from the underside plastic channel and routes to the top of the wheel arch where it connects to the inner hose. If the hard lines are too corroded then you can graft a replacement hard line in by cutting and making a joint inside the plastic channel underneath the car and route the new hard line to the wheel arch. The single long braided hose is an option worth considering, a cable tie would suffice as an extra mounting point to provde the extra support.

I see what you mean, ok I will investigate the condition of all hardline pieces around the area and report back. I know the car has had the long hardlines replaced 2 years ago (the ones that come up from the front of the car to the wheel arch).

I replaced the flexi+solid+flexi rear line with a single braided flexi because the unions on mine were shot.

I put the dimensions in the thread you've linked to and it worked fine.

Ah brilliant, I did not realise there was a page 2...

Thank you mate

 

[Ewazix]

I went with the full Wezmoto braided kit which eliminates the solid section on the rear, nicely made from quality materials I just need to find the time to fit them

 

[colb]

You will be OK with that set of hoses, you will find the ferrells on the old hoses will be quite corroded when you undo them so use a good fitting spanner to undo them. It also helps to prevent excess fluid loss when you disconnect the lines by using a length of wood to slightly depress the brake pedal, using the length of wood jammed agains the seat base and the brake pedal. Once you have all the new hoses fitted bleed the system starting at Rear nearside then rear offside then front nearside and finally front offside. Ensure you keep the master cylinder topped up as you go. Good tip is to suck some of the old fluid out of the master cylinder and replace it with new clean fluid before you start bleeding at the calipers. I used a vaccum bleeder to bleed mine which made it a one man job. All very easy for me with a car lift so all four wheels removed to carry out the job, bit more hassel if your using a jack and axle stand(s).

 

[Ewazix]

You will be OK with that set of hoses, you will find the ferrells on the old hoses will be quite corroded when you undo them so use a good fitting spanner to undo them. It also helps to prevent excess fluid loss when you disconnect the lines by using a length of wood to slightly depress the brake pedal, using the length of wood jammed agains the seat base and the brake pedal. Once you have all the new hoses fitted bleed the system starting at Rear nearside then rear offside then front nearside and finally front offside. Ensure you keep the master cylinder topped up as you go. Good tip is to suck some of the old fluid out of the master cylinder and replace it with new clean fluid before you start bleeding at the calipers. I used a vaccum bleeder to bleed mine which made it a one man job. All very easy for me with a car lift so all four wheels removed to carry out the job, bit more hassel if your using a jack and axle stand(s).

I originally replaced them about 8 years ago and I'd agree with your advice. On that occasion I used a Gunson eezibleed but it was useless, a cheap and nasty thing that spilled fluid down the engine bay so I went old skool, got someone to pump the pedal and binned the bleed'n Gunson :roll:

How many times have I told myself not to bother with cheap and nasty tools :fightwall:

 

[Ewazix]

I'm not sure how the OP iiNNex got on but with the MOT due next month I finally gone on and fitted my Wezmoto stainless braided hoses today, very nice kit and not difficult to fit, but I thought I'd pass on a couple of tips I found useful,

- With the Wezmoto kit you do NOT need the supplied copper washers on the calliper fittings (Wezmoto confirmed it's a kit covering several different cars, some need the washers but not the E85/86
- A proper 11 brake hose nut cut-out spanner will be a wise investment to prevent inevitable rounded-off nut. Just a few £quids at Halfords
- There is no need to remove the callipers
- I found that Cutting off the old rubber hoses makes undoing and manipulating the ferrule nuts easier (snips or secateurs did the job)
- Stick some plastic under the brake fluid cap to seal and create a vacuum (I had virtually no fluid loss)
- On the front remove the old top ferrule first the nut will release the hose enabling it to turn, then the calliper connection
- Likewise on the rear noting that you will be removing the solid link pipe in the middle of the rear hose, so undo the 10mm nut holding the bracket and remove the the old hose with the bracket as 99% chance that this part of the fitting will be corroded on solid. If you don't follow this you risk damaging the bracket.
- If the middle connection is rusted solid you are best cutting through the old ferrule with a disc or hacksaw, this will preserve your bracket and fitting.
- Install the rear in reverse order, calliper fitting first, then middle on the bracket, then top. The main fiddle is starting the threads, but all in all it's a surprisingly easy.

I'd recommend the Wezmoto kit, great quality materials and good value, having replaced the hoses about 8 years ago the stainless fittings are a nice upgrade. Now I must tidy up!