For 1990-2009 cars

### Disassembly Procedure

Important: The master cylinder reservoir cover and the reservoir diaphragm can be inspected and/or serviced without removing the master cylinder from the vehicle.

1. Wipe the reservoir cover (1) clean before removing.
2. Remove the master cylinder. Refer to Master Cylinder Replacement .
3. Remove the master cylinder reservoir cover (1) and the reservoir diaphragm (2).

Caution: Brake fluid may be irritating to the skin or the eyes, or may cause nausea, vomiting, or diarrhea if swallowed. In case of contact or swallowing take the following actions:

• | Eye contact - rinse thoroughly with water

• | Skin contact - wash with soap and water

• | If swallowed - Contact a physician immediately. Give two glasses of water and induce vomiting by sticking fingers down the throat.

Notice: Avoid spilling brake fluid on any of the vehicle's painted surfaces, wiring, cables, or electric connectors. Brake fluid will damage the paint and the electrical connections. If any fluid is spilled on the vehicle, flush the area to lessen the damage.

4. If the master cylinder is to be completely removed and overhauled, empty the fluid from the reservoir (3).
5. Inspect the master cylinder reservoir cover (1) and the diaphragm (2) for the following and replace any damaged parts:

• | Cuts

• | Cracks

• | Nicks

• | Deformation

6. Remove the fluid level switch (3).
7. Remove the piston snap ring (12) while depressing the primary piston (11).

Do not damage the following components:

• | The primary piston

• | The master cylinder bore

• | The piston retainer groove

8. Remove the primary piston and the primary piston spring.

In order to remove the parts, perform the following steps:

8.1. | Plug all of the outlet ports, except the upper outlet port.

8.2. | Apply low-pressure non-lubricated compressed air into the upper outlet port at the blind end of the bore.

9. Remove the following components from the secondary piston (9):

• | The primary seal (10)

• | The secondary seal (8)

• | The spring retainer (7)

10. Clean all of the parts with clean, denatured alcohol.
11. Dry the parts using non-lubricated compressed air.
12. Inspect the master cylinder bore for scoring or corrosion. Replace the master cylinder if scoring or corrosion is present.

### Assembly Procedure

1. Lubricate the rubber parts with clean brake fluid in order to ease assembly.
2. Lubricate and install the following components onto the secondary piston (9):

• | The primary seal (10)

• | The secondary seal (8)

• | The spring retainer (7)

3. Install the secondary piston spring (6) and the secondary piston assembly (9) into the cylinder bore. Lubricate the parts with clean brake fluid in order to ease assembly,
4. Install the lubricated primary piston (11) into the cylinder bore.
5. Install the piston retainer (12) while depressing the primary piston (11).
6. Install the fluid level switch (14).
7. Install the master cylinder reservoir diaphragm (2) into the reservoir cover (1).
8. Install the reservoir cover onto the master cylinder reservoir (3).
9. Install the master cylinder. Refer to Master Cylinder Replacement .