Brake Lines

[Harry]

I need to replace the right rear brake line from the flex hose to the wheel cylinder.  We have companies locally who can make one up for me but I want to be sure that I ask for the right size/flare.  I would request 5/16 steel line, with the ISO bubble flare - correct?  What is the metric fitting size that I need, please?

[cfm65@me.com]

Hi Harry,
Take the old one with as a sample.
Regards
Chris

[Harry]

Thanks.  I will but I don't have the ends or the fittings.

[cfm65@me.com]

Oh dear,
My car is in for a paint touch up, so I cant help right now. However, I will have a look see what I can do , but someone here will surely be able to come up with the correct info.
How about removing and using the one from the other side, as a sample?
Regards
Chris

[Benz Dr.]

A place like NAPA will have everything you need. I use a green-colored brake line and they should have the metric bubble flare ends.  I make my own lines when I have to.

[dirkbalter]

Thanks.  I will but I don't have the ends or the fittings.

Harry,
I believe it should be 3/16 instead of 5/16.
Just did the rear axle brake lines as well.
See here:
https://www.belmetric.com/bubble-flare-c-17_564_1107_1108/ble10x10bf475ylw-cohline-brake-end-p-11482.html

I bought their Copper Nickel brake lines (3/16") and like them. They bend nice and form the ends easy and good.

Hope that helps.

[ja17]

Yes, the new nickle copper alloy brake line is great to work with and never corrodes inside or outside. It is DOT approved for use. It is slightly less "puncture resistant" if you plan on crawling over rocks off road. It can be formed much more easily than the old steel lines. I recently replaced a main brake line with an OEM Mercedes brake line, and the new line seemed easier to bend than in the past. It also seemed less "magnetic" so I am wondering if Mercedes is also switching to a corrosion resistant alloy in there new OEM brake lines? It was slightly magnetic though, so it would be an alloy with some steel. Original rusty, pitted brake lines, can suddenly fail at the worst times, and should be replaced in any case!

https://rxmechanic.com/best-brake-line-material/

[Kevkeller]

I’m going to replace the entire brake system and clutch lines. They come in 25’ rolls, is that enough to do the entire car?

[TJMart]

Harry,
I believe it should be 3/16 instead of 5/16.
Just did the rear axle brake lines as well.
See here:
https://www.belmetric.com/bubble-flare-c-17_564_1107_1108/ble10x10bf475ylw-cohline-brake-end-p-11482.html

I bought their Copper Nickel brake lines (3/16") and like them. They bend nice and form the ends easy and good.

Hope that helps.

Dirk,

I have heard that stainless steel brake lines are good. Did you consider stainless vs the copper/nickel? Is there a significant difference?

I'm getting ready to completely restore my brake system so any advice is appreciated!

Thanks

Tony

[dirkbalter]

I don't have experience with stainless brake lines but assume that their "bendability" is similar to regular steel (or worse).  For that reason, I used the copper/nickel alloy ones. Easy and nice to work with.
I had bad experiences with purchasing pre-bend brake lines and their fitment and gave up one these.
(IMO nothing wrong with stainless)

[Leester]

I found the stainless to be a little hard to bend. After my lines were in under the car I wanted to make some fine adjustments so they were nice and parallel - especially at the front where they make the bend to come up into the engine compartment. It was a hard place to reach (I was laying on my back - no lift). If I were to do it again I would most likely try the nickel alloy.

[ja17]

According to what I have read, the nickel alloy lines handle more pressure than the plain steel lines. Stainless lines are the most difficult to bend and flare.

[Charles 230SL]

..We have companies locally who can make one up for me but I want to be sure that I ask for the right size/flare.  I would request 5/16 steel line, with the ISO bubble flare - correct?  What is the metric fitting size that I need, please?..

hi Harry, Dirk is right - you need 3/16 (4.75mm) fittings with Bubble Flare. Male Threading: M10X1.0 Extra Fine, used with a 4.75 European or 3/16 brake line. Here's another link with the specs:
https://belmetric.com/brake-end-m10x1-0-double-bubble-flare/?sku=BLE10X1.0BF4.75YLW.

Kevin, Sead built up all the brake lines for his 230SL: https://www.sl113.org/forums/index.php?topic=33340.msg243443#msg243443. One of his photos shows a 25 ft. roll of brake line - he might be able to remember whether one roll was enough for the entire car.

[Kevkeller]

Thanks. I bought one. I’ll see how it does.

[afibbe]

I’m in the process of replacing my rear brake lines from the master cylinder to the brakes. I have a bending tool but I have had better luck bending the tube by hand. I did use the bender for the short runs in order to get the perfect radius.

Practice using the bubble tool. Also don’t forget to put the fitting on the tube before you put the tube in the tool. I have had to cut off some beautiful bubbles because I forgot the fitting.

[dirkbalter]

Kevin,
here is an alternative source for the hardware, depending on what you are looking for. They ship thru amazon.
https://4lifetimelines.com/collections/fittings-1?filter.v.price.gte=0&filter.v.price.lte=120&filter.p.m.custom.thread_pitch=M10x1.0%22&sort_by=best-selling

Alex,
I found it helps if you lubricate the tool a bit when flaring.