Jeep CJ 1945-1970 Repair Information

Power Brake Booster


Brake linings may contain asbestos. Asbestos is a known cancer-causing agent. When working on brakes, remember that the dust which accumulates on the brake parts and/or in the drum contains asbestos. Always wear a protective face covering, such as a painter's mask, when working on the brakes. NEVER blow the dust from the brakes or drum! There are solvents made for the purpose of cleaning brake parts. Use them!

Clean, high quality brake fluid is essential to the safe and proper operation of the brake system. You should always buy the highest quality brake fluid that is available. If the brake fluid becomes contaminated, drain and flush the system, then refill the master cylinder with new fluid. Never reuse any brake fluid. Any brake fluid that is removed from the system should be discarded.


  1. Disconnect the power unit pushrod at the pedal.
  3. Disconnect the vacuum line at the power unit check valve.
  5. Unbolt the master cylinder from the power unit and push the master cylinder aside carefully.
  7. Unbolt the power unit bell crank at the dash panel and remove the power unit and bell crank as an assembly. If the power unit is being discarded, save the bell crank for the new unit.
  9. Installation is the reverse of removal. Tighten the bell crank-to-dash panel bolts to 35 ft. lbs. (48 Nm), the master cylinder-to-power unit bolts to 30 ft. lbs. (41 Nm), and the pushrod-to-pedal bolt and nut to 35 ft. lbs. (48 Nm).