Tips on Bleeding ABS Brakes

A car's braking system utilizes brake fluid to help transfer the stopping force from the car's master cylinder to the corners of the car. When the fluid in the braking system boils, it creates vapor that reduces the efficiency of the car's stopping ability. To improve and maintain a car's braking system, it is sometimes necessary to bleed the brake fluid to eliminate the vapors from the system.

Use the Proper Tools

Stoptech.com suggests having a box-end wrench on hand to loosen a car's bleeder screws, a pint of extra brake fluid (or three pints if you are completely replacing the fluid), and a foot-long piece of plastic tubing sized to the car's bleeder screws. Keep a bucket or small plastic bottle on hand to catch the brake fluid. Both the plastic tubing and the box-end wrench should be sized to fit a car's bleeder screws. Inspect the bleeder screws and find the right sized tools.

Loosen Lug Nuts Before Jacking Car

Before placing a car on the jackstands, be sure to loosen the wheel's lug nuts while the car is on the ground. Otherwise, the wheel spins as you try to get at the brakes when the car is raised. Also, as with any car procedure, be sure the car is firmly in place before proceeding (meaning jack the car on completely level ground and ensure that the wheels are properly in place and not slipping).

Use a Turkey Baster to Remove Old Fluid

Suck out the old fluid by using a turkey baster. Next, use a clean lint-free rag to clear the master cylinder reservoir of any remaining sediment. After securing the plastic tubing to the rear tire's bleeder bolt, top off the master cylinder reservoir with fresh brake fluid and close the cap tightly. Additionally, keep the master cylinder at least half full during the entire process. Stop bleeding the brakes periodically (every six or seven brake pumps) to refill.

Use an Assistant

Popular Mechanics and StopTech.com suggest using an assistant to help with this project. Instruct the helper to press down on the brake pedal and to keep the pressure on. As he presses down on the brake pedal, turn the bleeder bolt a quarter turn with a box-end wrench. Tell the assistant to keep the pressure on and wait until the fluid bleeds out of the line. When the fluid stops trickling out, tell him to release the brake. Keep repeating this process until clear, fresh fluid bleeds out.