Repairing power brakes is a very sensitive procedure that needs a lot of care.
Below are 5 steps for repairing power brakes.
Step 1: Initial Checks to Verify the Need for Brake Repairs
Most cars are equipped with a vacuum booster. The vacuum booster check, therefore, provides a quick means of verifying the effectiveness of your brakes. You can do this in 4 simple steps.
Switch off the engine.
Keep pumping the brake pedal until you completely bleed out the vacuum.
Hold the pedal down and simultaneously start the engine.
Confirm that the pedal depresses slightly as the vacuum refills.
If the refill does not occur, you’ve either have a blocked hose or a damaged booster.
If your car is fitted with a hydraulic-powered hydro-boost system, switch off the engine and follow the steps as detailed above. The failure of a vacuum refill signaled by the slight pedal depression on restarting the engine confirms a problem with your brake system.
Step 2: Gathering Necessary Tools and Materials
The tools needed for power brake repair include:
Service literature or manual guide
Air-operated tools—where applicable
Hand tools—where applicable
Materials needed for power brake repair include:
Brake proportioning valve
Power brake master cylinder and booster
Step 3: Actual Brake Installation
Power brake installation can be carried out in these quick steps:
Remove the old master cylinder after loosening the nuts
Slide new master cylinder into pre-existing studs projecting from the firewall
Tighten all studs with a power wrench
Lengthen the connecting brake lines, if necessary
Install the brake proportioning valve
Add the brake lines and thread down by hand
Tighten the brake lines using the appropriate wrench
Step 4: Bleeding the brakes
Bleeding the brakes takes 11 easy steps:
Leave your engine running (applicable to power brakes).
Disconnect the metal tubing carrying fluid to all of the wheels.
Depress the brake a couple of times then hold the pedal down.
Open the brake fluid reservoir.
Using a wire brush, clean the fitting where the brake liner enters the back of the wheel.
Using an appropriate wrench, loosen the brake line fitting.
Close fitting back (but not too tight).
Instruct a second person to depress the brake pedal a few times and then hold the pedal down.
Open fitting gently while a second person keeps the pedal depressed (old fluid spurts out).
Close the fitting when all of the pressure has been let out.
Repeat pedal pumping until the pressure builds up again.
Step 5: Final Safety Checks/Tips
Use Safety glasses.
Do not damage the brake lining fitting.
Keep pouring in the new brake fluid throughout the process of bleeding to keep all air out.
Remember to thread down lining by hand before using a wrench to ensure the proper fit.
Dispose of old fluid reasonably.
Following these simple steps, you can safely and reliably repair your power brakes.