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I need tips for replacing hard brake lines.

6.4K views 38 replies 15 participants last post by  kwilford  
#1 ·
I've got two cars here other than the Tinyvette, and by cars I mean GTs, because is there any other kind? Anyway, Rob's is getting a complete suspension and brake redo and that is going well. It is a California car (GT), last driven 15 years ago. Catherine's was a Colorado car (GT), stored in Wyoming, then in California, last driven 28 years ago. Catherine's car (GT) has the rust you'd expect, and it has been interesting. The engine runs well and she's got fresh brakes now, except when bleeding them the long hard line to the rear squirted fluid out. With the car (GT) all together replacing that looks like an interesting project. That's a long line! The car (GT) is on jack stands. I don't have a lift.

Any tips on how to proceed? Is it doable with a car (GT) just a foot off the ground, the engine and everything in, etc.?

I have a flaring tool. I guess I need to get a bending tool.

Mike
 
#2 ·
I bought the titanium coated lines that OGTS sells and I used a cheap pair of tubing bending pliers. It was fun! My car was stripped when I did it, though. Yes, you should be able to do the rear line with the car intact.

Front lines would be darn near impossible to do with the engine in the car.

:veryhappy

Tip: Start at the brakes and work your way towards the MC.
 
#13 ·
Really, I need to pull the engine? My left front brake line is broken off about an inch out of where it comes into the fender well. Do I need to order the whole OGTS Brake Tubing Set? No way to bend the tube with the engine in?


I bought the titanium coated lines that OGTS sells and I used a cheap pair of tubing bending pliers. It was fun! My car was stripped when I did it, though. Yes, you should be able to do the rear line with the car intact.


:veryhappy

Tip: Start at the brakes and work your way towards the MC.
 
#4 ·
I have 2 bending tools, a little one for tight radii and a bigger one, it took both to do the job. I used the OGTS kit. 12" off the ground will make it tough but you can do it. When you take the old lines off try to keep them somewhat intact so you have a good idea of what bends you have to make on the new ones. If it gets ridiculous with the engine in the car you can always split the line and put in a union but that does add 2 more possible leak points.
 
#5 ·
When I did my restoration of the yellow GT, I installed the engine first and ran the brake lines later. Wasn't that bad. I did it in my garage up on jack stands. I agree that you should remove the old lines first and then bend the new ones out on the floor to match them. Be sure to mark the connections at the MC. I know from experience that you can easily mix them up. If you do, you won't be able to bleed all 4 wheels.
 
#6 ·
Thanks. You're not discouraging me. ;)

I'd think for the long line to the rear that starting at the master cylinder would be best. There are more bends on that end.

I figure if I can poke the line through the hole in the radiator support first and have it go outside the engine cross-member support I'm off to a good start.

Seeing as the long line has a hole it in, I suppose I should think seriously about replacing all hard lines.

Mike
 
#7 ·
You can pick up a 50' roll of soft brake (bendable) line and just fish it through.
My son used that stuff for his fuel line and got it through the whole car in about 15 minutes. Brake lines shouldn't be much harder.
 
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#8 ·
I've recently started using 'cupro' brake lines....copper/nickel which bends nicely, doesn't work harden like soft copper, doesn't rust, and is DOT approved.
Definitely bends and flares easier than regular steel.
 
#10 ·
I have two of them.
 
#11 ·
The best tip for routing brake lines I ever came across, was to use electrical wire to create a model of all the bends you need to do. I liked the idea so much, I've never forgotten it. Maybe it will help you out when you can't really work under the car. Bend the wire by hand while under the car, then bend the tubing in a comfier position. Tape could help hold long pieces in place.
 
#14 ·
You don't "need" the OGTS set. You can determine the right length you need and buy from any auto parts store. OGTS just does the hard part for you. You could also buy the tube and a flange tool and make one from scratch.
You don't "need" to remove the engine. It's just easier if the engine is out.
 
#19 ·
Replacing the rears went well. I had to cut the line running to the front, twice. I figure to replace it I'll make the s-bend on the bench and do the rest after getting under the car. From the engine back will be pretty easy, but engine-forward wiill take a little more finesse.

I've got the OGTS brake line kit. It's pretty nice, but makes screwing up just that much more painful.

Mike
 
#20 ·
Bendable brake line is available at the parts store. So is a flange tool.

My son worked for a parts company so he'd buy stuff with his discount.
 
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#22 ·
I’ve replaced them with the engine in both of my cars. Not an easy job. The only way is to copy the bends of the original and you can slide everything through with a bit of cussing. I lived in the middle of nowhere at the time. The nearest store was over an hour away, so I used a vice to hold various socket sizes to make different radius bends. I didn’t kink it anywhere, just took my time.


Sent from my iPhone using Tapatalk
 
#23 ·
I've been using the vise/socket technique, too. It works, but you have to be careful.

I have a HF tubing bender that I'll use for the final bend to the master cylinder. I'll have to figure out how to handle the front brake lines. The radiator will definitely come out, probably the fan, too.
 
#24 · (Edited)
I'll have to figure out how to handle the front brake lines.
I found the bend that passes the line through the fender to R/L front brakes to be quite a PIA in regards to preventing it from pressing too hard against the grommet or sheet metal of the hole itself. It was hard to get the perfect bend so that the line was perfectly centered in the hole, while simultaneously being able to connect the line to the fitting on the caliper and clamping the line to the body in the engine compartment. I chose to supplement the rubber fender hole grommet with some rubber fuel line hose slipped over the line.

:veryhappy
 
#25 ·
I pulled off all my brake lines when I restored my GT's body. They were in very good condition, and just needed a bit of cleaning up to satisfy me, and I added a coat of fancy satin black Chassis Saver (similar to POR 15) urethane paint to make them even prettier. But one brake line, from the master cylinder to the right front wheel, had been replaced way back in the day (before I bought the GT in 1978), and rather than routing it back in the original position, someone must have decided to take an easier route. Worked fine, but didn't look so great. Since I had the engine (and everything) out, I decided to put the line back where it belonged.

I suspected (incorrectly) that the replacement line was the same length as original, although it turned out to be just slightly shorter than the OEM line. If I was simply replicating an existing brake line, I think it would have been quite easy, but the line in my GT was not properly shaped. I was able to use my garage-find GT (stored since 1975) as a guide, although I did not want to pull its brake line out, since it's restoration is several years away. I took several lengths of coat hanger wire and carefully bent them to match the OEM line, and then used the wire as a guide to re-form the line in my GT. When I discovered it was an inch or so short (argghhh!!!), I just took some of the more complex bends out of the design, and it worked great.

I had bought an assortment of brake bending tools, virtually every one that Gordo shows above, and a couple worked well to straighten my old brake line prior to re-forming. But in the end, I used the simple plier tool shown below for almost all the final bends, as it allowed that "in-place" forming that the bigger tools proved to cumbersome.

HTH
 

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#26 ·
The rear brakes have been replumbed. What a pain, especially working alone. Under the car, in the engine bay, under the car again, and so on for about an hour. But it went in OK and I had no do-overs.

For the long line to the rear I used a tubing bender to put the double kink in it, leaving the rest straight. I fed it in from the rear, several times so I could get it to pass on the fender side of the steering column. After that it was mostly gentle bends by hand and one 90 in the nose using the bending tool again.

I cleared the front (radiator, alternator, fan) and was scoping out those two lines, but had had enough. It was hot here today and I spent almost 9 hours on the silver GT yesterday.

Mike
 
#27 ·
I need to replace the driver side front brake line, from the master cylinder to the caliber - also need the specifications of the fittings. Can someone tell me the size of the line and the fittings and where I can purchase the materials, I have called the three major auto supply stores with no luck. I have never worked with brake line before so this will be a new experience. I just purchase the last Banjo from OGTS and I am afraid, that if I proceed, that I may cross thread the existing connector as it just does not feel right, so better safe than sorry. Thanking you in advance for your assistance.
 
#29 ·
Can someone tell me the size of the line and the fittings and where I can purchase the materials, I have called the three major auto supply stores with no luck.
Ditto for me.

Where does one buy brake line, other than OGTS? I presume I could save some money on materials and shipping if I didn't use their pre-cut tubing.

Does it have to be steel? Can I just use cheap copper line?

What kinds of chains or stores should have it?
 
#28 ·
The basic rule is to work from the brake back to the MC, this way any extra tubing can be bunched up under the MC, rather than in your wheel wells. Hoo-boy, I would not relish installing a front lines with the engine in place. When I did mine, my car was stripped and fresh back from the paint shop. I used cheap plier-like benders and they worked just fine.