Key points
- Brake line flaring is the process of creating a flared end on a brake line, which allows it to seal tightly against the fittings in the braking system.
- If a flared brake line becomes damaged, it is possible to repair it using a brake line flaring tool.
- After flaring and connecting all brake lines, it is essential to bleed the brake system to remove any air trapped in the lines.
Maintaining a well-functioning braking system is crucial for the safety of any vehicle. Brake lines, responsible for transmitting hydraulic pressure from the master cylinder to the calipers or wheel cylinders, play a vital role in this system. When old or damaged brake lines need replacement, proper flaring is essential to ensure a leak-free and reliable connection. In this comprehensive guide, we delve into the techniques and tools required to flare brake lines like a pro.
Understanding Brake Line Flaring
Brake line flaring is the process of creating a flared end on a brake line, which allows it to seal tightly against the fittings in the braking system. This flared end prevents leaks and ensures a secure connection. There are two main types of brake line flaring: single and double flaring.
- Single flaring: Involves creating a single, inverted cone-shaped flare at the end of the brake line. This method is commonly used for smaller brake lines, such as those found in older vehicles.
- Double flaring: Creates a more durable and leak-proof connection by forming two flares on the brake line. The first flare is a smaller, inverted cone, while the second flare is a larger, rounded flare. Double flaring is typically used for high-pressure brake systems, such as those found in newer vehicles.
Essential Tools for Brake Line Flaring
Before embarking on the flaring process, it’s crucial to gather the necessary tools:
- Brake line flaring tool
- Brake line cutter
- Deburring tool
- Brake fluid
- Clean rags
Step-by-Step Flaring Guide
1. Prepare the Brake Line
- Measure and cut the brake line to the desired length using a brake line cutter.
- Use a deburring tool to remove any sharp edges or burrs from the cut end of the brake line.
2. Choose the Flaring Tool
- Select the appropriate flaring tool for the type of flare you need (single or double).
- Ensure the flaring tool is clean and free of debris.
3. Insert the Brake Line
- Insert the brake line into the flaring tool, making sure it is fully seated.
- Tighten the clamping screw to secure the brake line in place.
4. Flare the Brake Line
- For single flaring, push down on the flaring die to create the inverted cone-shaped flare.
- For double flaring, follow the same step twice, creating a smaller inverted cone flare and then a larger rounded flare.
5. Inspect the Flare
- Carefully remove the brake line from the flaring tool.
- Inspect the flare to ensure it is uniform and free of any cracks or imperfections.
6. Clean and Lubricate
- Wipe the flared end of the brake line with a clean rag to remove any debris.
- Apply a small amount of brake fluid to the flare to lubricate it.
7. Connect and Tighten
- Insert the flared end of the brake line into the fitting.
- Tighten the fitting to the manufacturer’s specifications.
Advanced Techniques
Using a Bench-Mounted Flaring Tool
- Bench-mounted flaring tools provide greater stability and precision.
- Follow the same steps as with a handheld tool, but secure the brake line in the tool’s vise.
Flaring Stainless Steel Brake Lines
- Stainless steel brake lines require a specialized flaring tool.
- Use a high-quality tool and follow the manufacturer’s instructions carefully.
Repairing Flared Brake Lines
- If a flared brake line becomes damaged, it is possible to repair it using a brake line flaring tool.
- Cut off the damaged section of the line and flare the new end.
The Final Touch: Bleeding the Brake System
- After flaring and connecting all brake lines, it is essential to bleed the brake system to remove any air trapped in the lines.
- Follow the manufacturer’s instructions for the specific vehicle.
Questions We Hear a Lot
1. What is the difference between single and double flaring?
- Single flaring creates a single inverted cone-shaped flare, while double flaring creates two flares, an inverted cone and a rounded flare. Double flaring is stronger and more leak-proof.
2. Can I use a regular wrench to flare brake lines?
- No, a regular wrench will not provide the necessary precision and control. Use a dedicated brake line flaring tool.
3. How do I know if a brake line flare is leaking?
- A leaking brake line flare will typically be visible as a small leak or a wet spot around the connection. If you suspect a leak, inspect the flare and tighten the fitting if necessary.
4. How often should I inspect brake lines?
- Inspect brake lines annually for signs of damage or corrosion. Replace any damaged lines immediately.
5. Can I flare brake lines without a tool?
- It is not recommended to flare brake lines without a proper tool. Attempting to do so may result in a weak or damaged flare, leading to leaks and safety concerns.