Metal lines and rubber brake hoses should be checked frequently for leaks and external damage. Metal lines are particularly prone to crushing and kinking under the car. Any such deformation can restrict the proper flow of fluid and therefore impair braking at the wheels. Rubber hoses should be checked for cracking or scraping; such damage can create a weak spot in the hose and it could fail under pressure.
Any time the lines are removed or disconnected, extreme cleanliness must be observed. Clean all joints and connections before disassembly (use a stiff bristle brush and clean brake fluid); be sure to plug the lines and ports as soon as they are opened. New lines and hoses should be flushed clean with brake fluid before installation to remove any contamination.
REMOVAL & INSTALLATION
- If equipped with an air bag, disconnect the negative battery cable and properly disable the Supplemental Restraint System (SRS), as detailed in Chassis Electrical .
- Elevate and safely support the car on jackstands.
- Remove the wheel(s) as necessary for access.
- Clean the surrounding area at the joints to be disconnected.
- Place a catch pan under the joint to be disconnected.
- Using two wrenches (one to hold the joint and one to turn the fitting), disconnect the hose or line to be replaced.
- Disconnect the other end of the line or hose, moving the drain pan if necessary. Always use two wrenches if possible.
- Disconnect any retaining clips or brackets holding the line and remove the line.
- If the system is to remain open for more time than it takes to swap lines, tape or plug each remaining line and port to keep dirt out and fluid in.
- Install the new line or hose, starting with the end farthest from the master cylinder. Connect the other end, then confirm that both fittings are correctly threaded and turn smoothly using finger pressure. Make sure the new line will not rub against any other part. Brake lines must be at least 1 / 2 in. (13mm) from the steering column and other moving parts. Any protective shielding or insulators must be reinstalled in the original location.
- Using two wrenches as before, tighten each fitting to 9-12 ft. lbs. (13-17 Nm). Brake hoses connecting to front or rear calipers should be tightened to 25 ft. lbs. (35 Nm). Brake lines connecting to rear wheel cylinders (drum brakes) should be tightened to 14 ft. lbs. (19 Nm).
- Install any retaining clips or brackets on the lines.
- Refill the brake reservoir with clean, fresh brake fluid.
- Bleed the brake system.
- Install the wheels and lower the car to the ground.
- If equipped, enable the SRS system and connect the negative battery cable.
BRAKE PIPE FLARING
Flaring steel lines is a skill which needs to be practiced before it should be done on a line which is to be used on a vehicle. A special flaring kit with double flaring adapters is required. It is essential that the flare is formed evenly to prevent any leaks when the brake system is under pressure. Only steel lines, not copper lines, should be used. It is also mandatory that the flare be a double