B3000 SE Regular Cab 4WD V6-3.0L OHV (1998)
Brake Bleeding: Service and Repair
Master Cylinder - Bench Bleed
NOTE:
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When any part of the hydraulic system has been disconnected for repairer replacement, air can get into the system and cause spongy brake pedal
action. This requires bleeding of the hydraulic system after it has been properly connected. The hydraulic system can be bled manually or with
pressure bleeding equipment.
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When the brake master cylinder has been replaced or the system has been emptied or partially emptied, it must be primed to prevent air from
entering the system.
1. For in-vehicle priming, disconnect the brake lines from the brake master cylinder.
2. For bench priming, mount the brake master cylinder in a vise.
3. Install short brake tubes with the ends bent into the brake master cylinder reservoir.
1) Fill the brake master cylinder reservoir with the proper brake fluid.
4. For a new brake master cylinder, remove the brake pressure switch and fill with the proper brake fluid.
5. Install the brake pressure switch.
6. Slowly depress the primary piston or, for in-vehicle priming, have an assistant slowly pump the brake pedal until clear brake fluid flows from both
brake tubes with no air bubbles.
7. If necessary, install the brake master cylinder into the vehicle.
8. Remove the short brake tubes and install the master cylinder outlet tubes.
9. Loosen a brake outlet tube at the 4WABS hydraulic unit.
NOTE: Refill the brake master cylinder reservoir as necessary.
10. Have an assistant depress and hold the brake pedal.
11. Tighten the outlet tube fitting at the hydraulic unit.
12. Repeat the above three steps until no air bubbles are seen in the expelled brake fluid.
13. Repeat the above four steps for the remaining master cylinder outlet tube.
14. Connect one end of a flexible tube to the master cylinder bleeder screw. Submerge the other end in a container partially filled with the specified
brake fluid.
15. Have an assistant pump and then hold firm pressure on the brake pedal.
NOTE: Refill the brake master cylinder reservoir as necessary.
16. Loosen the master cylinder bleeder screw until brake fluid flows out of the drain tube.
17. Tighten the master cylinder bleeder screw.
18. Repeat the above three steps until there are no air bubbles in the expelled brake fluid.
19. Bleed the brake system.
