Nissan Sentra Service Manual: Brake master cylinder

Exploded View

1. Reservoir cap

2. Oil strainer
3. Reservoir tank
4. Cylinder body
5. Pin
6. O-ring
7. Grommet

Apply brake fluid

PBC (Poly Butyl Cuprysil)
grease or silicone-based grease

Removal and Installation

REMOVAL

CAUTION:

• Do not spill or splash brake fluid on painted surfaces. Brake fluid may damage paint. If brake fluid is splashed on painted areas, wash it away with water immediately.

• Do not scratch the piston of master cylinder when installing/removing because the piston is exposed. Check for any dust on the piston, and wash with brake fluid if needed.

• Hold the master cylinder body when handing the master cylinder assembly. Do not hold the piston because the piston might become detached if pulled strongly.

• Refill the reservoir tank with new brake fluid “DOT 3”.

• Do not reuse drained brake fluid.

• Do not reuse master cylinder O-ring.

NOTE:

When removing components such as hoses, tubes/lines, etc., cap or plug openings to prevent fluid from spilling.

1. Partially drain brake fluid. Refer to BR-17, "Drain and Refill".
2. Disconnect the harness connector from the brake fluid level switch.
3. Remove air duct and air cleaner case. Refer to EM-25, "Removal and Installation".
4. Remove the engine room insulator and position aside.
5. Separate the brake tube from master cylinder assembly with a suitable tool.

CAUTION:

Do not scratch the flare nut and the brake tube.

6. Disconnect the clutch hose (if equipped).
7. Remove the master cylinder assembly.

CAUTION:

• Do not deform or bend the brake tubes.

• Do not depress the brake pedal after the master cylinder assembly is removed.

• The piston of the master cylinder assembly is exposed. Do not damage the piston when removing the master cylinder.

• The piston may drop off when pulled out strongly. Do not hold the piston. Hold the cylinder body when handling the master cylinder assembly.

8. Remove and discard the O-ring.

CAUTION:

Do not reuse O-ring.

INSTALLATION

Installation is in the reverse order of removal.

CAUTION:

Do not reuse O-ring.

• Apply PBC (Poly Butyl Cuprysil) grease or equivalent to the brake booster (A) when installing the master cylinder assembly to the brake booster.

• Temporarily tighten the brake tube flare nut to the master cylinder assembly by hand. Then tighten it to the specified torque.Refer to BR-25, "FRONT : Exploded View".
• Perform the air bleeding. Refer to BR-17, "Bleeding Brake System".