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    Ford Pick-Ups/Expedition/Navigator 1997-2000

    Power Brake Booster

    Print

    REMOVAL & INSTALLATION



    F-150, F-250, Expedition and Navigator


    Click image to see an enlarged view

    Fig. Fig. 1 Brake booster assembly- F-150, F-250, Expedition and Navigator; 1999-00 F-Super Duty models with vacuum assisted booster

    1. Remove the master cylinder.
    2.  
    3. Disconnect the power brake booster hose.
    4.  
    5. Remove the stoplight switch self-locking pin.
    6.  
    7. Slide the stoplight switch and booster push rod off the brake pedal pin.
    8.  
    9. Remove the bulkhead sound insulator.
    10.  
    11. Remove the power brake booster nuts and remove the booster.
    12.  

    To install:

    1. The installation is the reverse of the removal.
    2.  

    1997-98 F-250HD, F-350 and F-Super Duty
    WITH HYDROBOOST BRAKES


    Click image to see an enlarged view

    Fig. Fig. 2 Hydro-Boost system on the F-Super Duty chassis cab



    Click image to see an enlarged view

    Fig. Fig. 3 Hydro-Boost system on the F-Super Duty commercial stripped chassis



    Click image to see an enlarged view

    Fig. Fig. 4 Hydro-Boost system on the F-Super Duty motor home chassis


    CAUTION
    Do not depress the brake pedal with the master cylinder removed!

    1. Depress the brake pedal several times with the engine off to exhaust the pressure in the accumulator.
    2.  
    3. Remove the master cylinder from the Hydro-Boost unit. Do not disconnect the brake lines from the master cylinder! Position the master cylinder out of the way.
    4.  
    5. Disconnect the 3 hydraulic lines from the Hydro-Boost unit.
    6.  
    7. Disconnect the pushrod from the brake pedal.
    8.  
    9. Remove the booster mounting nuts and lift the booster from the firewall.
    10.  


    CAUTION
    The booster should never be carried by the accumulator. The accumulator contains high pressure nitrogen and can be dangerous if mishandled! If the accumulator is to be disposed of, do not expose it to fire or other forms of incineration! Gas pressure can be relieved by drilling a 1 / 16 in. (1.5mm) hole in the end of the accumulator can. Always wear safety goggles during the drilling!

    1. Installation is the reverse of removal. Tighten the booster mounting nuts to 25 ft. lbs. (34 Nm); the master cylinder nuts to 25 ft. lbs. (34 Nm); connect the hydraulic lines, refill and bleed the booster as follows:
      1. Fill the pump reservoir with Dexron®II ATF.
      2.  
      3. Disconnect the coil wires and crank the engine for several seconds.
      4.  
      5. Check the fluid level and refill, if necessary.
      6.  
      7. Connect the coil wires and start the engine.
      8.  
      9. With the engine running, turn the steering wheel lock-to-lock twice. Shut off the engine.
      10.  
      11. Depress the brake pedal several times to discharge the accumulator.
      12.  
      13. Start the engine and repeat Step 6e.
      14.  
      15. If foam appears in the reservoir, allow the foam to dissipate.
      16.  
      17. Repeat Step 6e as often as necessary to expel all air from the system.
      18.  

    2.  

    The system is, in effect, self-bleeding and normal vehicle operation will expel any further trapped

    WITH VACUUM ASSISTED BOOSTER


    Click image to see an enlarged view

    Fig. Fig. 5 Brake booster assembly-1997-98 F-250HD, F-350 and F-Super Duty wit vacuum assist

    1. Disconnect the brake light switch wires.
    2.  
    3. Support the master cylinder from below, with a prop of some kind.
    4.  
    5. Loosen the clamp and remove the booster check valve hose.
    6.  
    7. Remove the wraparound clip from the booster inboard stud.
    8.  
    9. Remove the master cylinder from the booster. Keep it supported. It will not be necessary to disconnect the brake lines.
    10.  
    11. Working inside the truck below the instrument panel, disconnect the booster valve operating rod from the brake pedal assembly.
    12.  
    13. Remove the 4 bracket-to-dash panel attaching nuts.
    14.  
    15. Remove the booster and bracket assembly from the dash panel, sliding the valve operating rod out from the engine side of the dash panel.
    16.  

    To install:

    1. Mount the booster and bracket assembly on the dash panel by sliding the valve operating rod in through the hole in the dash panel, and installing the attaching nuts. Tighten the nuts to 18-25 ft. lbs. (24-34 Nm).
    2.  
    3. Connect the manifold vacuum hose to the booster.
    4.  
    5. Install the master cylinder. Tighten the nuts to 18-25 ft. lbs. (24-34 Nm).
    6.  
    7. Install the wraparound clip.
    8.  
    9. Connect the stop light switch wires.
    10.  
    11. Working inside the truck below the instrument panel, connect the pushrod and stoplight switch.
    12.  

    1999-00 F-250SD, F-350 and F-Super Duty
    WITH HYDRO-BOOST BRAKES


    Click image to see an enlarged view

    Fig. Fig. 6 Hydro-boost brake booster assembly


    WARNING
    The power brake booster should not be carried by the accumulator, nor should it ever be dropped on the accumulator. Check the snap ring on the accumulator for proper seating before the power brake booster is used. The accumulator contains high-pressure nitrogen gas and can be dangerous if mishandled.

    1. With the engine off, depress the brake pedal several times to discharge the accumulator.
    2.  
    3. Disconnect the negative battery cable.
    4.  
    5. Remove the left side battery.
    6.  
    7. Remove the air cleaner housing.
    8.  
    9. Remove the brake pressure switch electrical connector.
    10.  
    11. Disconnect the power steering pressure hoses.
    12.  
    13. Disconnect the power steering return line hose.
    14.  
    15. Remove the three power steering line clamp bolts.
    16.  
    17. Remove the brake master cylinder nuts.
    18.  
    19. Remove the power steering hose mounting bracket and the brake master cylinder, and position aside.
    20.  
    21. Remove the fuse panel cover.
    22.  
    23. Remove the stoplight switch self-locking pin.
    24.  
    25. Remove the stoplight switch and the brake booster push rod from the brake pedal pin.
    26.  
    27. Remove the power brake booster nuts, and remove the power brake booster.
    28.  

    To install:


    CAUTION
    If the accumulator is to be disposed of, it must not be exposed to excessive heat. Before discarding the accumulator, drill a 1 / 16 inch (1.6-mm) diameter hole in the end of the accumulator can to relieve the gas pressure. Always wear safety glasses when performing this operation.

    1. The installation is the reverse of the removal.
    2.  
    3. Install new Teflon® seals on the power steering pressure fittings.
    4.  

    WITH VACUUM ASSISTED BOOSTER


    Click image to see an enlarged view

    Fig. Fig. 7 Brake booster assembly- F-150, F-250, Expedition and Navigator; 1999-00 F-Super Duty models with vacuum assisted booster

    1. Disconnect the negative battery cable.
    2.  
    3. Remove the air cleaner housing.
    4.  
    5. Remove the brake master cylinder nuts.
    6.  
    7. Position the brake master cylinder aside.
    8.  
    9. Disconnect the booster vacuum hose.
    10.  
    11. Disconnect the power distribution box auxiliary relay and set aside.
    12.  
    13. Remove the fuse panel cover.
    14.  
    15. Remove the stoplight switch self-locking pin.
    16.  
    17. Remove the stoplight switch and the brake booster push rod from the brake pedal pin.
    18.  
    19. Remove the power brake booster nuts.
    20.  
    21. Remove the power brake booster.
    22.  

    To install:

    1. The installation is the reverse of the removal.
    2.  

    WITH HYDRO-MAX BRAKES


    Click image to see an enlarged view

    Fig. Fig. 8 Hydro-max brake booster assembly

    1. Disconnect the negative battery cable.
    2.  
    3. Remove the support bracket bolt and nut.
    4.  
    5. Remove the ground wire nut and the ground wire.
    6.  
    7. Remove the four master cylinder nuts.
    8.  
    9. Position the master cylinder aside.
    10.  
    11. Remove the electric motor relay bolt.
    12.  
    13. Detach the flow switch electrical connector.
    14.  
    15. Remove the steering column cover.
    16.  
    17. Remove the stoplight switch self-locking pin.
    18.  
    19. Remove the stoplight switch and the brake booster push rod from the brake pedal.
    20.  
    21. Detach the electric pump and motor assembly electric connector.
    22.  
    23. Disconnect the hydraulic fluid return hose.
    24.  
    25. Remove the hydraulic fluid supply line nut.
    26.  
    27. Remove the Hydro-Max booster nuts, and remove the Hydro-Max booster.
    28.  
    29. The installation is the reverse of the removal.
    30.  

    Start the hydraulic fluid supply line before tightening the Hydro-Max nuts and bolts.

     
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