### Master Cylinder

#### REMOVAL AND INSTALLATION

##### Sentra and 200SX

NOTE: Never reuse any brake fluid. Any brake fluid that is removed from the system should be properly discarded.

1. Clean the outside of the master cylinder thoroughly, particularly around the cap and fluid lines.
2. If equipped with a fluid level sensor, disconnect the wiring harness from the master cylinder.
3. Disconnect the brake fluid lines, then plug the openings to prevent dirt from entering the system.
4. Remove the mounting bolts at the firewall or the brake booster (if equipped) and remove the master cylinder from the vehicle.

   To install:

5. Bench bleed the master cylinder.
6. Install the master cylinder to the vehicle.
7. Torque the master cylinder mounting nuts to 9 ft. lbs. (12 Nm).
8. Connect all brake lines and fluid level sensor wiring if so equipped.
9. Tighten the brake line fittings to 12-14 ft. lbs. (17-20 Nm).
10. Refill the reservoir with brake fluid and bleed the system.

    NOTE: Use DOT 3 brake fluid in the brake systems.

11. Check for leaks and verify proper brake system operation.

##### Altima, Maxima and 1993-94 240SX and 300ZX

1. Disconnect the negative battery terminal and the electrical connector from the reservoir.
2. Clean the outside of the master cylinder thoroughly, particularly around the cap and fluid lines.
3. Disconnect the brake fluid tubes, then plug the openings to prevent dirt from entering the system.
4. Remove the master cylinder mounting nuts and remove the master cylinder from the vehicle.

   To install:

   Fig. 1:Measuring the output rod length -- Altima, Maxima and 1993-94 300ZX

   NOTE: At this point it will be necessary to adjust the output rod length.

5. Apply &minus;19.69 in. Hg of vacuum to the brake booster using a vacuum pump.
6. Measure the output rod length from the end of the rod to the front face of the booster.
7. The adjustment of the rod should be 0.4045-0.4144 in. (10.275-10.525mm).
8. Bench bleed the master cylinder assembly prior to installation.
9. Install the master cylinder and torque the master cylinder mounting nuts to the following specifications:
   1. 1993-97 Maxima, 1997 Altima and 1993-94 300ZX -- 9-11 ft. lbs. (12-15 Nm).
   2. All other vehicles -- 5.8-8.0 ft. lbs. (8-11 Nm).
10. Connect the brake lines.
11. Refill the reservoir with brake fluid and bleed the system. Adjust the brake system if necessary.
12. Connect the negative battery cable and the electrical to the bottom of the reservoir.

    NOTE: The adjustable pushrod is used to adjust the brake pedal free height.

13. Check for fluid leaks and verify proper brake system operation.

##### 1995-97 240SX and 300ZX

1. Disconnect the negative battery terminal.
2. Clean the outside of the master cylinder thoroughly, particularly around the cap and fluid lines.
3. Disconnect the brake fluid tubes, then plug the openings to prevent dirt from entering the system.
4. Remove the master cylinder mounting nuts and remove the master cylinder from the vehicle.

   To install:

5. Bench bleed the master cylinder assembly prior to installation.
6. Install the master cylinder and torque the master cylinder mounting nuts to 9-11 ft. lbs. (12-15 Nm).
7. Connect the brake lines and tighten the flare fittings to 11-13 ft. lbs. (15-18 Nm).
8. Refill the reservoir with brake fluid and bleed the system. Adjust the brakes, if necessary.
9. Connect the negative battery cable and bleed the entire brake system.

   NOTE: Ordinary brake fluid will boil and cause brake failure under the high temperatures developed in disc brake systems; use DOT 3 brake fluid in the brake systems.

10. Check for fluid leaks and verify proper brake system operation.

###### Master Cylinder Bench Bleeding

1. Place the master cylinder in a vise.
2. Connect 2 lines to the fluid outlet orifices and place them into the reservoir.
3. Fill the reservoir with brake fluid.
4. Using a wooden dowel, depress the pushrod slowly, allowing the pistons to return. Do this several times until the air bubbles in the brake fluid are gone.
5. Remove the bleeding tubes from the master cylinder, plug the outlets, and install the caps.