How to Flare Brake Lines

PDF download Download Article
PDF download Download Article

Flaring brake lines ensures a leak-proof connection without extra materials or sealants. If the brake lines aren't properly flared, you can lose fluid that will cause your brakes to fail. This article will explain how to flare your brake lines using single and double flares.

Steps

PDF download Download Article
  2. Advertisement
  3. [1]
    • Cutters will cut round tubing squarely without causing burrs. You will have to remove burrs if you use a hacksaw. [2]
  4. [3]
    • The instructions for both types of single flare tools are given below.
    • Lower the cone down until it is centered over the tube's end.
  6. Turn the advance screw to move the cone until the part of the tube being flared is firmly against the countersunk recess of the bar.
  7. If the line is damaged at all, replace it with a new one.
    8. Advertisement

Get Car Support Solve Any Problem

wH
Hi there! Do you have a question about how to diagnose or fix a problem with your car? I’ve read the manual so you don’t have to. Select your make, model, and year, then ask away!
*
*
Method 1
Method 1 of 2:

Generating Tool

PDF download Download Article
    • On a generating flare tool, the flare is formed in the air instead of in the recessed part of the bar.
  2. Check the manual for the number of revolutions needed for the flare size you need.
  3. If you end up with any damage, even a hairline crack, toss out the brake line and try again with a new one.
    4. Advertisement
Method 2
Method 2 of 2:

Double Flaring Tool (New Standard)

PDF download Download Article
  1. [4]
    • Ensure the depth is equal to the edge of your tubing size insert.
  2. [5]
    • Remove the insert and finish advancing the cone into the bell.
    • The bell shape of the tube forms the double thickness flare.
    3. Advertisement

Video

Community Q&A

Search
Add New Question
  • Question
    Can I use a single in an application where a double flare was used?
    Uglymug18
    Community Answer
    No. Double flare is used in high pressure ABS applications for a reason. A single flare is more likely to spit under high pressure, causing break failure.
    Thanks! We're glad this was helpful.
    Thank you for your feedback.
    If wikiHow has helped you, please consider a small contribution to support us in helping more readers like you. We’re committed to providing the world with free how-to resources, and even $1 helps us in our mission. Support wikiHow
    Yes No
    Not Helpful 0 Helpful 4
Ask a Question
200 characters left
Include your email address to get a message when this question is answered.
Submit
      Advertisement

      Tips

      • Practice flaring lines with some inexpensive tubing before flaring your vehicle's brake lines.
        Thanks
        Helpful 6 Not Helpful 2
      • The Society of Automotive Engineers recommends double flaring for all hydraulic brake lines.
        Thanks
        Helpful 1 Not Helpful 3
      • There are three types of flares: single flares, double flares, and bubble flares.
        Thanks
        Helpful 0 Not Helpful 1
      Submit a Tip
      All tip submissions are carefully reviewed before being published
      Name
      Please provide your name and last initial
      Submit
      Thanks for submitting a tip for review!
      Advertisement

      Warnings

      • Consult your tool's user guide for specific instructions. Tools' instructions can vary from manufacturer to manufacturer.
        Thanks
        Helpful 2 Not Helpful 2
      Advertisement

      Things You'll Need

      • Gloves and eye protection
      • Measuring tape
      • Brake tubing
      • Tube cutters or hacksaw
      • Single flare tool
      • Double flare tool

      You Might Also Like

      How to
      Bleed Car Brakes
      How to
      Remove Brake Drums
      How to
      Bleed Brake Lines
      How to
      Diagnose and Fix Problems with Your Electric Parking Brakes
      How to
      Change a Brake Caliper
      How to
      Check Your Brake Pads For Wear: Visual Signs & Measurement Tips
      How to
      Fix a Parking Brake Light That Won’t Turn Off
      Bad Brake Booster: Symptoms, Tests, and Troubleshooting
      How to
      Replace a Master Cylinder
      How to
      Change The Brake Pads in Your Car
      Brakes Locking Up While Driving? Causes & Fixes
      How to
      Bleed a Master Cylinder
      Testing and Adjusting Your Vehicle's Rear Drum Brakes
      An Expert-Approved Guide to Replacing Brake Rotors Like a Pro
      Advertisement

      References

      1. ↑ https://www.youtube.com/watch?v=IpT3jEnmmRs
      2. ↑ https://www.hotrodhotline.com/md/html/flaring_brake_line_3.php
      3. ↑ https://www.youtube.com/watch?v=IpT3jEnmmRs
      4. ↑ https://robrobinette.com/flare_brake_line.htm
      5. ↑ https://robrobinette.com/flare_brake_line.htm
      6. http://www.hotrodhotline.com/md/html/flaring_brake_line_3.php

      About This Article

      Thanks to all authors for creating a page that has been read 132,651 times.

      Reader Success Stories

      • Anonymous

        May 23, 2017

        "Awesome! I did it years ago, but could not remember just what to do."
      Share your story

      Did this article help you?

      Advertisement