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Power Brake Units - BENDIX Dual Diaphragm: Overhaul: Reassembly

  1. Press new bearing and seal into rear housing. The flat rubber surface of the seal should be 5/16" below flat, inside surface of rear housing.
  2. Place reaction disc in hub of front plate with small tip toward hole. Use a rounded rod to seal disc. Place holding mandrel (J-22839) in a vise.
  3. Place front diaphragm on front plate with long fold of diaphragm down. Place a suitable seal protector (J-22733) over threads on front plate hub.
  4. Apply a light film of silicone lubricant to front plate hub and to seal in center plate. Guide center plate, seal end first, onto front plate hub. Care must be taken not to damage center plate seal. Remove seal protector.
  5. Apply a light coat of silicone lubricant to bearing surfaces of air valve plunger. Care must be taken not to get lubricant on rubber grommet inside plunger.
  6. Install square ring seal on shoulder of front plate hub. Install valve plunger return spring and plunger in base of front plate hub.
  7. Set rear plate over front plate hub. By hand only, screw plate on hub. Make sure valve and spring are correctly aligned. Tighten plates to 150 INCH lbs. by hand. Check plunger travel.
  8. Assemble rear diaphragm to rear plate. Place lip of diaphragm in rear plate groove. Install diaphragm retainer over rear diaphragm and lip of center plate. Press retainer until it seats on shoulder of center plate.
  9. Apply talcum powder to rear housing inside wall. Apply silicone lubricant to scalloped cutouts of front housing and seal in rear housing.
  10. Install diaphragm and plate assembly into rear housing. Carefully guide rear plate hub through seal in rear housing.
  11. Bosses on center plate must be aligned between lances in rear housing for reassembly. Work outer rim of front diaphragm into rear housing using a screwdriver. Make sure it is under lances in housing.
  12. Attach holding fixture (J-22805) to front housing studs. Position front housing and holding fixture in an arbor press.
  13. Place spanner wrench (J-9504) over studs on rear housing. Bolt wrench to studs. Place piece of pipe used during disassembly over plastic diaphragm plate hub. Place a piece of flat stock over pipe.
  14. Install return spring so that small end of spring is against housing. Place rear housing over front housing and align scribe marks. Rotate spanner wrench clockwise until housings lock together.
  15. Bend tabs' in 4 deep lances back to original position. Remove spanner wrench and holding fixture.
  16. Wet poppet valve with denatured alcohol. Install in rear plate hub, small end first. Wet poppet retainer with denatured alcohol and assemble with shoulder inside poppet.
  17. Install retainer, filters and silencer over ridge on rod. Install return spring over ball end of operating valve rod. Wet grommet in valve plunger with denatured alcohol. Guide air valve rod into valve plunger.
  18. Tap end of operating valve rod with plastic hammer to lock ball in grommet. Press filters and silencer into hub and install retainer on hub.
  19. Install silencer in dust boot. Wet boot opening with denatured alcohol. Install over operating rod and rear housing flange. Install new check valve and grommet.
  20. Apply silicone lubricant to piston end of push rod. Insert in front plate cavity. Twist rod to eliminate air bubbles at reaction disc. Assemble seal over push rod and press into recess in front housing.
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