Brake Booster - DELCO-Moraine Tandem Diaphragm: Reassembly
- Place power piston on bench with push rod end up. Install assembly cone (J-28458) over push rod end of piston. Lubricate inside diameter of secondary diaphragm with silicone lubricant and fit in secondary support plate.
- Install secondary diaphragm and support plate over power piston and push down until it bottoms. See Fig 1. Lubricate inside diameter of secondary power piston bearing and install in housing divider with flat surface of bearing on the same side as 6 raised lugs on divider.
Courtesy of GENERAL MOTORS CORP.
- Hold divider so that formed over flange faces up. Press divider down over assembly cone and onto power piston to rest against secondary diaphragm. Lubricate inside diameter of primary diaphragm and install in primary support plate.
- Remove assembly cone from power piston. Place primary support plate and diaphragm assembly over power piston and push down until it bottoms. Place diaphragm retainer over power piston and onto diaphragm.
- Install assembly cone (J-28458) over power piston onto diaphragm retainer and strike with hammer until retainer is locked on neck of power piston. Remove assembly cone.
- Install reaction retainer, piston rod, and power head silencer. Place primary power piston bearing in rear housing center hole. Lubricate with silicone lubricant on inner diameter.
- Install rear housing in Holding Fixture (J-23456). Attach power piston assembly to rear housing. Install power piston assembly to rear housing. Install power piston return spring over reaction retainer and lower front housing onto rear housing aligning scribe marks.
- Tighten fixture handscrew just enough to allow for housing rotation. Rotate housing until tabs are fully seated. Stake 2 housing tabs into sockets at 2 new locations 180° apart. DO NOT
stake tabs that have previously been staked.
- Lubricate inside and outside diameters of grommet and front housing seal. Install seal, grommet, vacuum check valve, silencer, and push rod boot.