Loosening and removing any rusty part can be a challenge, but removing a rusted brake line can be even tougher. That's because brake line fittings can be rounded off with a wrench fairly easily, which can make the process even more frustrating. Removing the line takes a combination of specialty tools and the right lubricants to break up the rust and get the line free.
Spray penetrating oil onto the brake line fitting for removal, making sure to get between the fitting and the brake assembly, as well as where the brake line goes into the fitting. This will break up the rust and make it a bit easier to remove. Allow the oil to sit for at least an hour then repeat this process before proceeding.
Place a line wrench on the fitting. The line wrench wraps around the fitting, providing more points of contact, and should have an extremely tight fit. If there is any slack at all, get the correct size of line wrench and try again. Attempt to remove the fitting. If it doesn't budge, proceed to Step 3.
Slide the steel tubing over the end of the wrench, providing a longer lever to pull on, then begin turning the line wrench. Pull the tubing by the far end to get the most leverage until the fitting breaks loose.
