Power Brake Booster: Disassembly

Install Accumulator Piston Compressor (J-26889) on master cylinder mounting stud and retain with nut. See Fig 1 and Fig 2. Compress accumulator using "C" clamp.
Insert punch into hole in housing. Release clamp and remove accumulator piston compressor. Remove accumulator and "O" ring. Remove retainer, spool plug, "O" ring and spool return spring from spool plug bore.
Remove baffle, output pushrod, spring and baffle retainer, piston return spring and spring retainer. Saw off eyelet on pedal rod. Remove pedal rod boot, bracket nut and bracket. Remove housing cover bolts. Separate cover from housing.
Remove seal from end of rod on piston assembly. Remove housing seal. Remove piston assembly and piston seal. Remove spool valve. Remove accumulator valve using wire hook. See Fig 3. Remove return port fitting and "O" ring.

Fig 1: Compressing Accumulator

Courtesy of GENERAL MOTORS CORP.

Fig 2: Exploded View Of Bendix Hydro-Boost Power Brake Booster

Courtesy of GENERAL MOTORS CORP.

Fig 3: Removing Accumulator Valve Using Fabricated Tool

Courtesy of GENERAL MOTORS CORP.