Why bleed brakes

Many experts recommend bleeding the brake system when maintaining your brakes. The purpose of bleeding the brakes is to remove any trapped air from the brake lines. This guide will help you with the art of bleeding the brakes.

In normal operation, you do not need to bleed the brake system. Yet, there are some situations that will require bleeding it:. You will experience these issues:. Air stays in the brake system until you bleed the system.

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The hydro-boost unit uses power steering fluid pressure. STEP 2: Jack up your vehicle on level, solid ground preferably a garage floor or driveway and support it with four jack stands placed at the jacking points shown in the owner's manual. You can always prop it up on cinder blocks if you want your neighbors to start worrying about their property values.

It needs to be safely on solid footing while up in the air; the process of bleeding brakes will have you climbing partially under the car at times.

Remove all four wheels. STEP 3: Locate each of the four caliper bleeding screws, one of which is shown in a typical location in the above illustration. Drum brakes also have similar bleeder screws. If they're difficult to break loose, spray them with penetrating oil, let it soak in for a half-hour, and then attempt to loosen them again. If they snap off or strip, stop at once and take your vehicle to a shop and let a professional deal with the issue.

Once you've loosened each bleed screw, snug it back up again; you'll be bleeding one brake at a time, and the other screws need to be closed so no air gets sucked into the system. Air bubbles are the enemy of brakes systems; they make your brake pedal feel mushy and reduce the system's performance.

STEP 4: Get the hood up and check the fluid level in the brake master cylinder reservoir. Its location is likely shown in your owner's manual. Make sure you've got the correct fluid for your vehicle see step 1. During brake bleeding, the master-cylinder cap should be left unscrewed but still in place atop the reservoir. Once a year as part of good preventive maintenance.

Here are the four brake bleeding methods: Gravity : Put a container under the bleeder screw, open the screw and let gravity draw the old fluid into the container. Be prepared for some cleanup afterward. Manual :Put a container under the bleeder screw, and open it while another person slowly pushes and releases the brake pedal, forcing the fluid and air out.

Work the brakes smoothly to avoid creating more air bubbles that might linger, contaminating the new fluid. Pressure :Again, put a container under the bleeder screw and open it. Then, use a tank of pressurized brake fluid at the master cylinder to push the fluid and air through the system and out into the container.