How to Troubleshoot Automobile Brake Problems

Maintaining a well-functioning brake system reduces your risk of having a stopping-related car accident. Due to normal wear and tear, brake problems occur. The cost of hiring a professional mechanic to troubleshoot your vehicle becomes quite expensive when you add it to the cost of performing the necessary repairs. You can solve this problem and reduce your out-of-pocket expenses by troubleshooting your brake system beforehand.

Instructions

Soft Brake Pedal

1

Remove all brake lines from the master cylinder using the correct wrenches. Plug the lines with the outlet plugs. Apply pressure to the brake pedal. Instruct your mechanic to replace the bore of the master cylinder or the seals if the pedal remains spongy. Unplug and reattach the brake lines to the master cylinder.

2

Instruct your mechanic to replace hard lines, which are lines that loop up higher than the master cylinder and then back down.

3

Instruct your mechanic to install an inline 10-pound residual pressure valve if it's missing. The valve can be found in the rear lines coming into the master cylinder and is made of black rubber.

4

Instruct your mechanic to replace the booster pin if it is more than 1/64 inch away from the master cylinder.

5

Bleed your brakes. Have the bleeder screw repositioned by your mechanic if it's not located on the highest point on the cylinder chamber.

Hard Brake Pedal

6

Turn your engine off and pump the brake pedal six times. Apply moderate pressure to the brake pedal and turn your engine on. Instruct your mechanic to replace your power booster if the brake pedal does not move slightly toward the floor.

7

Check your vacuum level according to the vacuum gauge instructions. Notify your mechanic if the vacuum level measures below 16 inches.

8

Instruct your mechanic to replace your wheel cylinder if it is frozen.

No Brake Pedal Pressure

9

Instruct your mechanic to replace any broken or cracked seals on your master cylinder.

10

Have your mechanic replace the booster pin if it does not come in contact with the master cylinder.

11

Tighten all bleeder screws using the correct wrenches. Inspect to see if all bleeder screws are properly positioned high on the calipers and pointing up. Have your mechanic reposition them if they are not.

12

Instruct your mechanic to replace low drag calipers with the correct size. According to Master Power Brakes, "The metric low drag caliper can be identified by a chamfered leading edge of the square cut groove for the piston seal."

Dragging Brakes

13

Shim the master cylinder 1/32 inch off of the booster. Have your mechanic adjust the booster pin inward if brake drag disappears.

14

Instruct your mechanic to replace the parking brake cable if it is frozen as well as frozen cylinder and caliper pistons.

15

Inspect brake drums for tightness. Have your mechanic loosen them if they are found to be too tight.

16

Instruct your mechanic to replace a drum master cylinder with one made for disc breaks to eliminate drag.