Brake line leak

[Adonaischild]

We had new tires put on our '92 Cadillac Seville and the tire guy mentioned a leak in our brake line behind the left rear wheel. My husband took a look at it and said it looks like the caddy has one continous line from front to back. How do you fix a leak on something like that?

[Bruce Nunnally]

I would want to get a complete new line. But the shop manual for the 05 suggests you can repair the brake pipe (brake line).

Check the description here.

Apparently you use a specialized tool to cut out a section of the current brake line, then splice in a new section to replace the leaking portion.

Are you certain the leak is FROM the pipe (brake line) and not simply running along the pipe but leaking from somewhere else such as the rear caliper then dripping down along the brake line?

This repair would strike me as a good thing for the Dealer to do.

[KHE]

Is the leak on the metal line itself or the rubber portion near the suspension? From your description, it sounds like the metal line. Buy a section of brake line from an auto parts store - your car uses the ISO/bubble flare. Cut the bad section out with a tubing cutter and then connect the new line to the caliper and bend it to the shape of the old line to follow the same routing. Cut the opposite end off the new line at the spot where you want to join it to the existing line and use a compression fitting to connect the lines. If it is the rubber line, that can be replaced and is available at any auto parts store.

You will then need to bleed the caliper on that side to remove the air from the line. It is important to use a tubing cutter and ream the inside diameter of the cut.

You should inspect the remaining brake lines for corrosion. A slight amount os normal but if any lines are significantly corroded, it is a good idea to replace them before they start leaking.

[MrEldo97]

You will also need to acquire the proper ISO/double bubble flaring tool.

If you use a single flare flaring tool the repair won't seal.

You may be well advised to have a shop make the repair and check all of the remaining hard lines,

replacing any that are badly rusted.

[rek]

If you decide to replace all the lines..........

OTC "Stinger" 4504 Metric Bubble (ISO) Flairing Tool Set....(E-bay)...Cheap

25' Roll NAPA Coated Brake line....Should be 3/16"....measure to be sure...

Soak fittings with Blaster Penatrating Oil....

Use tube wrench....Quick "Snap" to loosen.

Cut off just the "Bubble" portion of the old line.

Bend new line using "Old" as template, add length to new line for flare as per gauge in kit.

Reuse tube nuts after wire brushing clean.

Cut tubing with a SHARP Tubing cutter....Easy does it....A DULL tubing cutter or "Anxious" cutting, WILL work-harden the tube end resulting in a "Poor" Flare.

Remove coating, add tube nut, a drop of oil on tube end and flare tool, and make the flare.

[Adonaischild]

Wow. I'll let my husband read this, but it sounds pretty involved. I guess we may have the break down and take this one to the shop.

Thanks!

[lothos]

If you decide to do this yourself, keep in mind that if you cut off one section and try to replace it another section might break and need to be replaced as well. I live in Minnesota, and I had the brake line rust through this past winter not too long after I bought my STS. I ended up replacing most of my brake line from front to back outside in the blowing snow in 25 degree weather with hand tools and a floor jack. It took me three days because I'd never done anything besides an oil change, I had to teach myself how to do the double flare, and I ran out of pipe and the store was closed, and the next day the tool kit broke and the store was closed, I was wearing gloves and taking breaks to warm up, etc etc. I don't mean to scare you off of doing this, everything I do to my car seems to take 2 or 3 times longer than everyone else simply because I'm new to it. It was easier than I thought it would be, though. And I saved hundreds of dollars over bringing it to a shop.

Checker Auto rents the brake tool kit, I think you guys have those in Wisconsin. I used the ultimate kit which was a deposit of $130 or so, but you get all your money back when you return it, making it free. The brake lines and fittings are pretty cheap.

[Phillip]

Brake lines can be pretty expensive to replace in a shop so it is tempting to do it yourself. If you do go DIY, either invest in, or borrow, some good tools. The flaring tool described above is a must. Practice with an end of tubing until your joints look good, then go at the car. Also, get GOOD flare nut wrenches. On my '96, there were 10mm nuts on the lines. In order to move these without stripping them, you have to have a good wrench. If you really have to, you can break the old lines and remove the old fittings with a six point socket, but you need a flare nut wrench to install the new ones tight enough. One of the fitting on the rear wheel of my car was so difficult, I had to use a 10mm, flare nut crow foot socket. That was hard to find, but the local Snap On dealer was able to get me one.

Good luck. If you decide to do it yourself, keep us posted. We may be albe to offer some advice along the way.