Brake line questions

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Dimi555
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Brake line questions

Post by Dimi555 »

I have a 1988 M6 (Euro spec) and I was wondering will the brake lines for a 1988 635csi fit on my 1988 M6. Apparently, BMW lists different part numbers for the brake lines. Does anyone have any experience with this? I don't want to wait weeks for the M6 lines to come from Europe if I can just use the 635csi part numbers.
Last edited by Dimi555 on Tue May 11, 2021 8:32 pm, edited 1 time in total.
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Dimi555
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Re: Brake line questions

Post by Dimi555 »

Man, sure is quiet 'round here. [crickets]
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hornhospital
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Re: Brake line questions

Post by hornhospital »

One of two possibilities:

Those that know haven't seen you posting yet,

Or,

Those that have seen you posting don't know. Like me.
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
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Dimi555
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Re: Brake line questions

Post by Dimi555 »

Hmm. Good point.

I just changed my profile picture to a lovely pair of tits. That ought to attract more people to my posts.

Now I just wait...
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hornhospital
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Re: Brake line questions

Post by hornhospital »

ROFLMAO!!!!

Well played, sir!
Ken Kanne
'84 633CSi "Sylvia"; '85 635CSi "Katja";'85 325e "Hazel Ann"; '95 M3 "Ashlyn"
GRNSHRK
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Re: Brake line questions

Post by GRNSHRK »

Agreed, classic =D>

While I don't own an M6 or M635, IIRC, the front calipers are 4-piston, which require 2 separate brake lines per side :-k

And a "standard' 635 would have single piston calipers, so only one line per side would be needed :-"

Again, not sure by any means, but me thinks that they are not compatible [-X
:mrgreen:
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Dimi555
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Re: Brake line questions

Post by Dimi555 »

Thanks for the feedback, gents.
emac
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Re: Brake line questions

Post by emac »

My 87 USA M6 has a single line feeding the caliper. Fluid travels through the caliper to the other side, but it does have two bleed screws.

The previous owner "upgraded" the caliper lines. Unless you just have to have OEM, you may want to try some vendors that sell aftermarket DOT lines.
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Re: Brake line questions

Post by bpoliakoff »

If you are not mechanically challenged, this may help. I went to Autozone and bought some of the largest lengths of brake lines they had. So bending those to replicate the original is a no brainer as the tubing bends easily. Just can't do tight 90 degree bends by hand.. A lot of the bends I did were by placing a large socket in my vice and just bending the tubing around that, You can get pretty tight 90 degree bends that way. Here is where the limited mechanical ability comes in. You will have to double flare the ends of the tubing where the fit into any port. This requires a tool that can do double flares and can probably be bought at a Napa store. Most kits have the ability to do single and double flares and won't bankrupt you,
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.
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Da_Hose
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Re: Brake line questions

Post by Da_Hose »

I will add that you might need bubble flare on the ends. I can't remember for sure. If it's bubble flare, you probably won't find that tool for loan, or purchase locally. I picked one up online, and have used it several times. Works awesome in the vice. A little more of a pain to do manually under a car, but still works well. I replaced lines under my daughter's Mini, and created a splice where an existing line would have been a nightmare to completely replace.

I highly recommend getting both the long lever type of bender for lines you can remove and replicate, along with the kind that looks like pliers with a curved head that you can just twist. The pliers really help when working in-situ.

Jose
1987 M6 - My dream car
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Re: Brake line questions

Post by bpoliakoff »

Bubble flare is needed. I think I picked my tool up at NAPA. It does regular flares or bubble flares. IThere are 2 different kinds of pliers. One is for making slight bends or adjustments the othe has a circular wheel in it that will bend a nice radioused bend. when the handles are squeezed together.
81 Euro 635 M90 with motronic. Currently under a complete nut and bolt restoration. Pictures at
flickr.com/photos/bertsphotos.
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