Ease of replacing brake lines?

Camhabib

TJ Enthusiast
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Mar 30, 2019
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Location
Boston, MA
So one of my brake lines exploded on my 98 TJ Sahara w/ ABS a few months ago. I ordered the replacement lines and they've been sitting in my basement since, waiting for some nice weather to give it a try. I enjoy getting to wrench myself, but I'm wondering if this is worth trying to do on my own or should I just suck it up and have a shop swap and flush everything for me? Anyone run into problems with the lines not coming out or having difficulty flushing the lines? Should I bother replacing the reservoir or anything else while I'm at it?
 
Brakes are very important. It doesn’t require any super special skill, but it does require competent ability. Line wrenches are not a must but they are a specialty tool to make the job easier and most cases successful. If your line ends are rusty it could make things more difficult. It will require bleeding the system. Some find the task of bleeding difficult, but it is not it just requires a certain level of knowledge. If your system has never or periodically had the fluid replaced now would be a good time. If your master cylinder functions properly there should be no reason to replace. Brakes are very important.
 
The pre-bent brake lines are much easier than building your own and having to flare them. As mentioned, if the lines are rusty, then so may be your wheel cylinders or blocks where they convert to rubber lines. Depending on which lines you're replacing, they aren't too bad. As far as bleeding/flushing, this can easily be accomplished with a hand pump/vacuum with a bottle setup like this pump.
 
Are you talking hoses (rubber) or hard lines?

Neither is hard to do. We custom make replacements all the time. (Hard lines)

You don't need a new master cylinder. The worst mistakes people make doing lines themselves is they don't get the fittings tight enough and they don't bleed the system properly.
 
The pre-bent brake lines are much easier than building your own and having to flare them. As mentioned, if the lines are rusty, then so may be your wheel cylinders or blocks where they convert to rubber lines. Depending on which lines you're replacing, they aren't too bad. As far as bleeding/flushing, this can easily be accomplished with a hand pump/vacuum with a bottle setup like this pump.
Already have line wrenches and a pump is on my list of things to pick up if I do this myself, but I'm still not sure how well it'll work with the ABS module.
Are you talking hoses (rubber) or hard lines?

Neither is hard to do. We custom make replacements all the time. (Hard lines)

You don't need a new master cylinder. The worst mistakes people make doing lines themselves is they don't get the fittings tight enough and they don't bleed the system properly.
Hard lines, though given how rusted those are, it wouldn't surprise me if some other stuff needed to be replaced as well. I was reading how to tighten the fittings properly, by tightening them down and then backing them off a few times in a row. The lines already come flared and with fittings, so that part is out of the way.
 
Already have line wrenches and a pump is on my list of things to pick up if I do this myself, but I'm still not sure how well it'll work with the ABS module.

Hard lines, though given how rusted those are, it wouldn't surprise me if some other stuff needed to be replaced as well. I was reading how to tighten the fittings properly, by tightening them down and then backing them off a few times in a row. The lines already come flared and with fittings, so that part is out of the way.
No worries. Cut the line you're working on right at the fitting. (Not the fitting but right after leaving just a 16th or so of line remaining.

Use a 6 point socket of proper size and take the old out.

Line wrenches are nice for assembly but old corroded fittings many times can only be removed with a 6 point socket.

****Make sure you use the proper size socket. Again.. corrosion on the outside and debris can distort the fitting size and prevent you from getting the proper socket on.
 
Be gentle with the plastic line clips on the frame. The 4 or 5 line clip that carries brake, fuel vent, and fuel near the left upper rear control arm, and the two below the grill tend to be brittle. Many workarounds are possible, but OEM quality replacement clips are not available (based on my experience shopping at local parts stores).
 
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No worries. Cut the line you're working on right at the fitting. (Not the fitting but right after leaving just a 16th or so of line remaining.

Use a 6 point socket of proper size and take the old out.

Line wrenches are nice for assembly but old corroded fittings many times can only be removed with a 6 point socket.

****Make sure you use the proper size socket. Again.. corrosion on the outside and debris can distort the fitting size and prevent you from getting the proper socket on.
Good tips, thanks.
Be gentle with the plastic line clips on the frame. The 4 or 5 line clip that carries brake, fuel vent, and fuel near the left upper rear control arm, and the two below the grill tend to be brittle. Many workarounds are possible, but OEM quality replacement clips are not available (based on my experience shopping at local parts stores).
Zip ties have become my go-to for things like this.
 
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I sometimes have done brake jobs without a helper. I made an adapter that fit a rubber drain coupler over the top of the brake fluid reservoir, and attached to an air compressor. Doesn't need much psi, like 10. Then you can just lay underneath it, crack the bleeder and fluid comes right out. Just make sure to go a little at a time, pausing to fill the reservoir. You don't want to empty it.

Works fine with ABS. What you don't want to do with ABS is push fluid back the wrong direction.
 
I know this is an older thread. But, since there was talk about bleeding brakes.....this is the best tool I have for bleeding brakes. I also have a Motive pressure bleeder but really prefer the vacuum bleeder. I've bled brakes with a hand held vacuum pump. It works but I'd rather not to it that way any more. You do need an air compressor. I used it the other day when replacing my rear brakes/wheel cylinders.

https://www.harborfreight.com/pneum...t-57057.html?_br_psugg_q=brake+bleeding+tools

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