How Do I Replace the Master Brake Cylinder on a 1992 Pontiac Bonneville SE?

The master brake cylinder is essential to the proper operation of the Pontiac Bonneville braking system. Without it, there is no way to distribute the fluid necessary to stop the car throughout the system. When you know that you need to replace the master cylinder, do not drive your car or you risk not being able to stop. It does not take long to replace the master cylinder. You can do it in your driveway in about two hours.

Instructions

1

Pop the hood on the car and locate the master cylinder on the back firewall. It will be on the driver's side. Siphon the fluid from the reservoir with a turkey baster. Place the fluid in a drain pan for recycling. Disconnect the negative battery cable, using a wrench to loosen the terminal nut.

2

Unplug the fluid level sensor (if there is one) on your master cylinder by unplugging it. Disconnect the reservoir hose and plug it if your car has an ABS system. Disconnect the brake lines from the master cylinder with a wrench. Use a wrench to loosen the collar nuts and remove the bolts from the master cylinder to the power booster. Pull the master cylinder away from the power booster assembly and out of the car.

3

Place the new master cylinder against the power booster and fasten the bolts with a wrench. Attach the brake lines to the master cylinder and tighten the collar nuts with the wrench. If your Bonneville has an ABS system, connect the reservoir hose to the master cylinder. Plug in the fluid level sensor if your car has one.

4

Add fresh brake fluid to the master cylinder. Starting with the rear passenger wheel, have someone to help you pump the brake pedal several times and hold it while you open the bleeder valve at the wheel to let the air out of the system. Repeat the process on all wheels until the air is gone.