Vacuum Brake Booster: Service and Repair

MASTER CYLINDER AND BRAKE BOOSTER





REMOVAL AND INSTALLATION

CAUTION Do not remove the check valve from the vacuum hose. If the check valve is defective, replace it together with the vacuum hose.

INSTALLATION SERVICE POINT
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1. Install the vacuum hose to the brake booster nipple as shown in the figure. Secure the hose using the hose clip.

CAUTION
1. The check valve and the pipe part of the brake booster must not contact each other.
2. Connect so that the marking faces upwards.

2. Install the other end of the vacuum hose fully onto its port on the engine. Secure the hose using the hose clip.

CLEARANCE ADJUSTMENT BETWEEN BRAKE BOOSTER PUSH ROD AND PRIMARY PISTON

Adjust the clearance (A) between the brake booster push rod and primary piston as follows:
Calculate clearance A from the B, C and D measurements. A = B - C - D
Standard value: 0.65-0.85 mm (0.0256-0.0335 inch)

NOTE When brake booster negative pressure 67 kPa (9.7 psi) is applied, clearance value will become 0.1-0.3 mm (0.004-0.012 inch).

If the clearance is not within the standard value range, turn the push rod screw to achieve desired length.