BLEEDING BRAKE SYSTEM

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Trevor Newman
6 years ago
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1 BLEEDING BRAKE SYSTEM CAUTION: Brake fluid is harmful to painted and plastic surfaces. If brake fluid is spilled onto a painted or plastic surface, immediately wash it with water. Bleed hydraulic system whenever air has been introduced into system. Bleed master cylinder and brakes at all 4 wheels if master cylinder lines have been disconnected or master cylinder has run dry. Bleed brakes with pressure bleeding equipment or by manually pumping brake pedal while using bleeder tubes. Always bleed brakelines in sequence. See BLEEDING SEQUENCE. Before bleeding system, remove all vacuum from power unit by depressing brake pedal several times. Bleed master cylinder first, followed in sequence by rear wheel cylinders, anti-lock system components (if equipped) and calipers. See BLEEDING SEQUENCE. COMPONENT BLEEDING DO NOT allow reservoir to run dry during bleeding operation. Master Cylinder Bleeding (Bench) 1. Support brake master cylinder body in a vise, and fill both fluid brake master cylinder reservoirs with brake fluid. 2. Install short brake tubes with the ends bent into the brake master cylinder reservoir. See Fig Slowly depress the primary piston until clear brake fluid flows from both brake tubes with no air bubbles. 4. Install the brake master cylinder into the vehicle. Remove the short brake tubes and install the master cylinder outlet tubes. 5. Refill the brake master cylinder reservoir as necessary. 6. Have an assistant depress and hold the brake pedal. Loosen a brake outlet tube at the master cylinder one at a time. Tighten the outlet tubes. 7. Repeat procedure until no air bubbles are seen in the expelled brake fluid. 8. Bleed the brake system. See SYSTEM BLEEDING. Wednesday, November 12, :30:30 4:30:35 PM Page Mitchell Repair Information Company, LLC.

2 Fig. 6: Bleeding Master Cylinder Courtesy of FORD MOTOR CO. Master Cylinder Bleeding (On-Vehicle) 1. Using a line wrench, disconnect the brake lines from the brake master cylinder. Install short brake tubes in master cylinder and position them so they curve into master cylinder reservoir, and ends of tubes are submerged in brake fluid. See Fig Fill master cylinder reservoir with clean brake fluid. Have an assistant pump brakes until clear, bubblefree fluid flows from both brake tubes. 3. Remove the short brake tubes and install the master cylinder outlet tubes. Refill the brake master cylinder Wednesday, November 12, :30:30 PM Page Mitchell Repair Information Company, LLC.

3 reservoir as necessary. 4. Have an assistant depress and hold the brake pedal. Loosen a brake outlet tube at the master cylinder one at a time. 5. Tighten the outlet tubes. Repeat procedure until no air bubbles are seen in the expelled brake fluid. 6. Bleed the brake system. See SYSTEM BLEEDING. Four Wheel Anti-Lock Brake System Hydraulic Control Unit This procedure only needs to be performed if the 4-Wheel Anti-Lock Brake System (4WABS) Hydraulic Control Unit (HCU) has been installed new. 1. Clean all dirt from and remove the brake master cylinder filler cap, and fill the brake master cylinder reservoir with the specified brake fluid. 2. Connect a clear drain tube to the right rear bleeder screw and the other end in a container partially filled with recommended brake fluid. See Fig Have an assistant pump the brake pedal and then hold firm pressure on the brake pedal. 4. Loosen the right rear bleeder screw until a stream of brake fluid comes out. While the assistant maintains pressure on the brake pedal, tighten the bleeder screw. Repeat until clear, bubble-free fluid comes out. Refill the brake master cylinder reservoir as necessary. 5. Tighten the bleeder screw. 6. Repeat procedure for the left rear bleeder screw, the right front bleeder screw and the left front bleeder screw, in that order. See BLEEDING SEQUENCE. 7. Connect the scan tool DLC cable adapter into the vehicle data link connector (DLC) under the dash, and follow the scan tool instructions for bleeding. Go to HELP menu on the scan tool. The Ford Service Function Card (FSF) must be used to get the help menu. 8. Repeat the conventional bleed procedure in steps. Gravity Bleeding Fill brake master cylinder with new brake fluid. Loosen both wheel cylinder bleeder screws and leave them open until clear brake fluid flows. Check master cylinder reservoir fluid level often and do not let it run dry. Tighten wheel cylinder bleeder screws. One at a time, loosen caliper bleeder screws. Leave bleeder screws open until clear fluid flows. Check fluid level often. Tighten caliper bleeder screws. SYSTEM BLEEDING Manual Bleeding 1. Clean all dirt from and remove the brake master cylinder filler cap and fill the brake master cylinder reservoir with the specified brake fluid. 2. Place a box end wrench on the right rear bleeder screw. Attach a rubber drain tube to the right rear bleeder screw and submerge the free end of the tube in a container partially filled with clean brake fluid. See Fig Have an assistant pump, and then hold firm pressure on, the brake pedal. Wednesday, November 12, :30:30 PM Page Mitchell Repair Information Company, LLC.

4 4. Loosen the right rear bleeder screw until a stream of brake fluid comes out. While an assistant maintains pressure on the brake pedal, tighten the right rear bleeder screw. Repeat until clear, bubble-free fluid comes out. Refill the brake master cylinder reservoir as necessary. Tighten the right rear bleeder screw. 5. Repeat procedure at bleeder fitting at left rear wheel cylinder, right front caliper, then left front caliper, in that order. See BLEEDING SEQUENCE. When bleeding is complete, fill master cylinder to proper level. Fig. 7: Bleeding Caliper/Wheel Cylinders (Typical) Courtesy of FORD MOTOR CO. Pressure Bleeding 1. Clean master cylinder cap and surrounding area. Remove cap. Master cylinder pressure bleeder adapter tools are available from various manufacturers of pressure bleeding equipment. Follow the instructions of the manufacturer when installing the adapter. Wednesday, November 12, :30:30 PM Page Mitchell Repair Information Company, LLC.

5 2. Install the bleeder adapter to the brake master cylinder reservoir, and attach the bleeder tank hose to the fitting on the adapter. Bleed the longest line first. Make sure the bleeder tank contains enough specified brake fluid to complete the bleeding operation. 3. Place a box end wrench on the right rear bleeder screw. Attach a rubber drain tube to the right rear bleeder screw, and submerge the free end of the tube in a container partially filled with clean brake fluid. See Fig. 7. See BLEEDING SEQUENCE. 4. Open the valve on the bleeder tank. Loosen the right rear bleeder screw. Leave open until clear, bubblefree brake fluid flows, then tighten the right rear bleeder screw and remove the rubber hose. 5. Continue bleeding the rest of the system, going in order from the left rear bleeder screw to the right front disc brake caliper bleeder screw, ending with the left front disc brake caliper bleeder screw. See BLEEDING SEQUENCE. 6. Close the bleeder tank valve. Remove the tank hose from the adapter, and remove the adapter. BLEEDING SEQUENCE BLEEDING SEQUENCE Application ABS Models Sequence (1) RR, LR, RF, LF (1) Perform FOUR WHEEL ANTI-LOCK BRAKE SYSTEM HYDRAULIC CONTROL UNIT procedure under COMPONENT BLEEDING, if the 4-Wheel Anti-Lock Brake (4WABS) Hydraulic Control Unit (HCU) has been installed new. Wednesday, November 12, :30:30 PM Page Mitchell Repair Information Company, LLC.

GENERAL PROCEDURES. Component Bleeding. Master Cylinder Priming In-Vehicle or Bench

GENERAL PROCEDURES. Component Bleeding. Master Cylinder Priming In-Vehicle or Bench 206-00-1 Brake System General Information 206-00-1 GENERAL PROCEDURES Component Bleeding Special Tool(s) Worldwide Diagnostic System (WDS) 418-F224, New Generation STAR (NGS) Tester 418-F052, or equivalent