How to Replace a Master Cylinder on 1994 Honda Accord

The center of your Accord's hydraulic brake system is the master cylinder. Although low brake fluid in the reservoir is one sign of a faulty master cylinder, it may actually be caused by worn brakes. Therefore, make sure all areas of the braking system are working, before replacing the master cylinder. If the brake pedal seems to drop to the floor when the Accord is at a stop, the master cylinder may be leaking internally and in need of replacement.

Instructions

Removing the Master Cylinder

1

Open the engine compartment. Use a syringe to take out as much brake fluid as possible from the reservoir.

2

Remove the brake line fittings from the master cylinder with your flare-nut wrench. Disconnect the brake lines, and cap them with threaded plastic plugs. Catch any spilled fluid with rags.

3

Remove the electrical connector from the master cylinder.

4

Unscrew, and remove, the mounting nuts on both sides of the master cylinder, using your wrench. Remove the master cylinder from the brake booster studs.

Bench Bleeding the New Master Cylinder

5

Wrap the master cylinder mounting flange with shop rags. Mount the cylinder in a vise, and clamp it. Set a container below the cylinder to catch brake fluid.

6

Install plastic threaded plugs into the brake line outlet holes, and slightly tighten them.

7

Add DOT 3 brake fluid to the reservoir.

8

Unscrew one of the plugs, and force the piston assembly into the master cylinder bore with a large Phillips screwdriver. This pushes out air from inside the master cylinder.

9

Tighten the plug back onto the master cylinder. Release the piston assembly.

10

Repeat Step 4 and Step 5, until only brake fluid comes out of the outlet holes.

11

Remove the master cylinder from the vice.

Installing the New Master Cylinder

12

Position the master cylinder over the brake booster studs. Install the mounting nuts, and finger-tighten them.

13

Screw the brake line fittings into the master cylinder, and finger-tighten them.

14

Torque the mounting nuts to 132 inch-pounds with your torque wrench. Tighten the brake line fittings with your flare-nut wrench. Connect the electrical connector.

15

Add more DOT 3 brake fluid to the reservoir.

16

Bleed the master cylinder by asking someone to depress, and hold, the brake pedal, while you loosen the brake line fittings to let air out. Keep rags under the cylinder to catch spilled fluid. Repeat, until you don't see any air bubbles in the fluid.

17

Bleed the brake system.

18

Check the operations of the brake system before driving on the road.