How to Install a New Master Cylinder
The master cylinder is the heart of a vehicle's brake system. It is responsible for holding and sending out the brake fluid to apply the necessary pressure needed to activate the brakes. Installing the part can be a tedious process, especially when bleeding the brake lines. Be sure to have a friend help you out when installing a new one.
Required skill level: Intermediate
Needed tools and materials
Preparing the vehicle
Be sure to park your car in a cool, shady area like the inside your garage. Working for extended periods under the sun could lead to heat exhaustion and possibly heat stroke.
Draining the master cylinder
Open the hood of your vehicle and locate the master cylinder; most can easily be identified because of the plastic fluid reservoirs attached on top of them. Try consulting a repair manual if you're having difficulty doing so.
Removing the old master cylinder
Disconnect the brake fluid level sensor. Remove all the hoses or fluid lines connected to the master cylinder. Remove all the bolts securing the master cylinder and set them aside before removing the master cylinder itself.
Installing the new master cylinder
Mount the new master cylinder in its proper place before securing it with the appropriate bolts. Reattach all the hoses and fluid line before reconnecting the fluid level sensor.
Bleeding the brake system
Decide what side of the vehicle you want to work on first: the front or the back. Jack up the side you will be working on and support it with jack stands. Remove the wheels and locate the bleeder valves of the brake system. Attach a fluid hose to the valve and submerged the end in a container with brake fluid. Have an assistant depress the brake before opening the bleeder valve. Wait for all the air bubbles and brake fluid flow from the hose before closing the valve. Repeat the process a few more time until all the air has been taken out of the brake line. Repeat the whole thing for the three other bleeder valves.
- Bleed the bake lines properly after installing the master cylinder. Failure to do so may lead to malfunctioning brakes.