I'm posting this in General because I hope it'*... ummm... general enough not to have to go in the repair sections.

I gotta replace a rusty old rear brake line. It comes aft under the drivers side door sills, there'* a union, then it bends around in a half loop and heads off across the car forward of the fuel tank to the right rear wheel.

In an ideal world, or, I suppose, a brake shop, I'd pull a length of tubing, bend it to shape, use my handy hydraulic swaging tool to put tidy double flares on each end and be done with it.

Problem here is, this is a long one, so I'm going to have to piece it together from at least a couple of lengths. That, and the place where it joins with the run forward is rotted, too. I'm going to have to go another foot or so forward and cut it off, or else replace that whole run, too.

So how do I, the backyard mechanic, do this repair?

How do you join brake lines if there isn't a flare already there for you?

I've been told you shouldn't use compression fittings on brake lines. The handful of times I have in the past it was always a dicey proposition whether I'd get a decent seal or not, given such stiff, brittle, thin-walled tubing. Is there even a little rust? Ferget it!!

A single flare never seemed to seal very well, assuming you could keep the tube from splitting in the attempt and leaking horribly.

Is there a way, short of buying a $400 hydraulic swaging tool I'll use once every 5 years, to put a double flare on brake line tubing? Can I borrow or rent one somewhere?

Now assuming I can make the connection with the forward part, am I just supposed to string together whatever lengths of pre-fabbed brake line I need to make up the total length?

And finally, what about the wire wrapped sections? Am I supposed to try to do that as well? How?

Any other suggestions or advice for the old dog trying to learn new tricks? :lol:

Thanks!

Mike D.

Just go to the parts store and buy a flaring tool? They're usually $20 at the most. I've never heard of someone using some $400 anything to make a flare in a brake line.

Also, be sure to add your year and trim to your signature.

Personally I hate dealing with hydraulic plumbing...so i took it to a shop to have done. Paid a pretty hefty price for the crappy job they did too. Would have been better off doing it myself.

I got my double falring tool and 25' of stainless for under $200 from Jeggs a few years ago. I don't see stainless kits anymore but they have the galvanized for under $90

Okay, popatim and wj, are we talking about a manual double flare tool here?

I guess I need to spend some time with Google. Can you point me to an example of something like you bought, popatim?

I mean, I've got the flaring tool you'd use on copper plumbing tubing, like for gas lines, but every time I've tried to use it on a brake line it tends to split, and even when I'm successful, a single layer flare doesn't seem to seal real well in the standard brake line fittings, at least for me.

What am I missing here?

Even a $75 or $100 tool I could justify for the amount of money the repair would save us. Much more than that, though, and it'* becoming too big a fraction of the value of the car, sadly enough. (I hate road-salt... <sigh>)

Thanks, very much!

Mike D.

heres a link to a basic double flare tool for around $25 and i've seen cheaper in parts stores

http://www.sears.com/shc/*/p_10153_1...ble+flare+tool

i wouldn't recommened tieing prefabed double flared lines together with unions, as that means more places to leak, like popatim said before i would get around 25 feet of steel tubing (only steel, never copper or alluminum), a tube cutting tool, a double flare kit, and the fittings that you would need.
the line is flexible enough that you can bend it by hand and under no circumstance except in a dire emergency use compression fittings, they are only designed to hold a few hundred pounds of pressure while a brake system can produce a few thousand pounds of pressure

I wish it was that easy.

I don't know what year GM made the change but 99'* don't use the double flare brake lines. They're ISO flares also known as bubble flares. Most brake lines are 3/16" but not these. These are 6mm.

When we bought my son'* 99 we found the line from the master cylinder to ABS module was leaking. Advance has adaptors that let you use 3/16" double flare lines. We would like to change all the lines using the 6mm bubble flares but haven't been able to find the 6mm brake line.

Thanks, Jason! I just spent some time with Google!

Such a simple answer! Double flaring tool sets are about everywhere! I just never knew to look for them. D'oh!

Where do I find long lengths of tubing? A hydraulics supply or someplace that caters to racing or customs? I've never seen any at Auto Zone!

Okay, I can do this!

Mike D.

Mike I think most Auto parts stores will carry the tubing. Just ask, you could buy a large roll of it if you wanted too.

Ed

Did you read my post?

i almost forgot about bubble flares on certain gm'*, i haven't done brake lines on my car yet, but have done them on several others (mainly chevy trucks and ford cars) at my job.

i usually get metric line from napa or robbins in 25 foot rolls, and a bubble flare tool is just as easy to come by as a double flare tool, and in my opinion are eaiser to do than double flares because their is only one step involved. As for the wire wrapped sections in your first post, i usually don't worry about that, as long as you carefully put a few loops in the line before the master cylinder (if your just going to the abs unit then you'll be ok)