Q: How to inspect and replace brake hoses and brake lines on Mercury Mariner?
A: About every six months, inspect the flexible hoses that connect the steel brake lines with the front and rear brake assemblies for cracks, chafing, leaks, blisters, and other damage. Use a light and mirror for a thorough check. If any of the hoses exhibit these defects, replace them with new ones. Clean dirt away from the ends of the hose. To disconnect a brake hose from the brake line, unscrew the metal tube nut with a flare nut wrench, remove the U-clip from the female fitting at the bracket, and remove the hose from the bracket. Disconnect the hose from the caliper, discarding the sealing washers on either side of the fitting. Attach the new brake hose to the caliper or wheel cylinder using new sealing washers. To reattach a brake hose to the metal line, insert the end of the hose through the frame bracket, ensuring it isn't twisted, and attach the metal line by tightening the tube nut fitting securely. Install the U-clip at the frame bracket. Carefully check for contact between the hose and suspension or steering components. Have an assistant push down on the vehicle and turn the steering wheel lock to lock during inspection. Bleed the brake system. When replacing brake lines, use the correct parts and avoid using copper tubing. Purchase steel brake lines from a dealer parts department or auto parts store. Prefabricated brake lines with flared tube ends and fittings installed are available and can be bent to the proper shapes using a tubing bender. Ensure the new line is well supported in the brackets and has sufficient clearance from moving or hot components. After installation, check the master cylinder fluid level and add fluid as necessary. Bleed the brake system and test the brakes carefully before normal operation.