Vacuum Brake Booster: Adjustments

1. Remove master cylinder as outlined under Master Cylinder, Brakes, then proceed as follows:

Fig. 5 Distance B Measurement Between Master Cylinder End Face & Piston:

a. Measure distance between master cylinder end face and piston, Fig. 5. Position a square (straight scale) against edge of master cylinder, then measure and subtract thickness of the square to determine dimension B.

Fig. 6 Distance C Measurement Between Brake Booster Mounting On Master Cylinder & End Face:

b. Find dimension C by measuring distance between brake booster mounting surface and the end face, Fig. 6.

Fig. 7 Distance D Measurement Between Master Cylinder Mounting Surface & Pushrod End:

c. Measure distance between master cylinder mounting surface and the pushrod end, Fig. 7. Find dimension D by subtracting the square's thickness from the measurement taken.

Fig. 8 Brake Booster To Primary Piston Clearance Dimension A:

d. Find brake booster to primary piston clearance dimension A, Fig. 8, using the formula A = B - C - D. Refer to Specifications for proper clearance specifications.

Fig. 10 Brake Booster Pushrod Adjustment:

e. If dimension A is not as specified, adjust brake booster pushrod as shown, Fig. 10.