Hydraulic System Bleeding :---
When any part of the hydraulic system has been disconnected for service, air may enter system and cause spongy pedal action. Bleed the hydraulic system after it has been opened to
make sure that all air is expelled.
Due to the diagonal braking system on this vehicle (LH front and RH rear on one circuit and RH front and LH rear on the other), bleeding the front brakes first allows for a shorter flow path
for air entrapped in the replacement valve. Once the front brakes have been thoroughly bled, the only volume of air remaining to be eliminated in the upper section of the ABS valve is the
air in the short sections of the rear brake tubes not accessible by the front brakes via the ABS valve.
Brake Master Cylinder Bleeding :-----
When a new brake master cylinder (2140) has been installed or the brake system emptied or partially emptied, fluid may not flow from the bleeder screws during normal bleeding. It may be
necessary to prime the system using the following procedure: ---------
1. Use a tubing wrench to remove the brake tubes from the master cylinder.
2. Install short brake tubes in the brake master cylinder and position them so that they point back into the reservoir and the ends of the pipes are submerged in brake fluid.
3. Fill the reservoir with new Ford High Performance DOT-3 Motor Vehicle Brake Fluid C6AZ-19542-AA or DOT-3 equivalent meeting Ford specification ESA-M6C25-A.
4. Cover the reservoir with a clean shop towel.
5. 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.
Pump the brakes until clear, bubble-free fluid comes out of both brake tubes.
6. Remove the short brake tubes and reinstall the ones from the vehicle.
7. Bleed each brake tube at the brake master cylinder using the following procedure: ---
a. Have an assistant pump the brake pedal 10 times and then hold firm pressure on the pedal.
b. Loosen the front brake line fitting with a tubing wrench until a stream of brake fluid comes out. Have your assistant maintain pressure on the brake pedal until the brake line
fitting is tightened again.
c. Repeat this operation until clear, bubble-free fluid comes out from around the tubing fitting.
d. Repeat this bleeding operation at the rear brake line fitting.
8. If any of the brake lines or calipers have been removed, it may be helpful to prime the system by gravity bleeding it. This should be done after the brake master cylinder is primed and
bled.
To prime the brake system: ----
a. Fill the brake master cylinder reservoir (2K478) with clean Ford High Performance DOT-3 Motor Vehicle Brake Fluid C6AZ-19542-AA or equivalent meeting Ford specification
ESA-M6C25-A.
b. Loosen both rear caliper bleeder screws and leave them open until clear brake fluid flows out.
Be sure to check the reservoir fluid level often and not let it run dry.
c. Tighten the bleeder screws.
d. One at a time, loosen the front caliper bleeder screws. Leave the bleeder screws open until clear fluid flows out. Be sure to check the reservoir level often and not let it run dry.
e. Tighten the bleeder screws to 7-9 Nm (61-87 lb-in).
9. After the brake master cylinder has been primed, the lines bled at the brake master cylinder, and the brake system primed, normal brake system bleeding can resume at each wheel.
Manual Bleeding :-=--
1. NOTE: During hydraulic system bleeding, maintain sufficient brake fluid level in the brake master cylinder reservoir to prevent air from entering the system.
Clean all dirt from brake master cylinder filler cap (2162).
2. If brake master cylinder is known or suspected to have air in bore, it must be bled before any of the wheel cylinders or calipers. To bleed brake master cylinder, loosen front outlet
fitting approximately three-quarter turn.
3. Have assistant push brake pedal (2455) down slowly through full travel. Close outlet fitting, then return pedal slowly to full released position. Wait five seconds; then repeat operation
until air bubbles cease to appear at the outlet fitting.
4. Loosen rear outlet fitting approximately three-quarter turn.
5. Repeat Step 3.
6. To continue to bleed brake system, remove rubber dust cap from bleeder screw. Place suitable box wrench on bleeder and attach rubber drain tube screw. The end of tube should fit
snugly around bleeder screw.
7. Submerge free end of tube in container partially filled with clean brake fluid and loosen bleeder screw approximately three-quarter turn.
8. Have assistant push brake pedal down slowly through full travel. Close bleeder screw; then return the brake pedal to full release position. Wait five seconds; then repeat this
operation until air bubbles cease to appear at submerged end of bleeder tube.
9. When fluid is completely free of air bubbles, secure bleeder screw and remove bleeder tube. Install rubber dust cap on bleeder screw.
10. Repeat this process on opposite diagonal system. Refill brake master cylinder reservoir as necessary and install the brake master cylinder filler cap. When bleeding operation is
completed, fluid level should be filled up to or within 3.0 mm (0.125 inch) of the MAX line on the brake master cylinder reservoir.
11. Always make sure disc brake pistons are returned to their normal positions by applying brake pedal several times until normal pedal travel is established.
12. Check pedal feel. If the brake pedal feels "spongy," repeat bleed procedure.
Pressure Bleeding
For pressure bleeding, use bleeder-type bleeder tank only, such as Rotunda Brake Bleeder 104-00064 or equivalent.
Bleed longest line first on the system being bled. The bleeder tank should contain enough new brake fluid to complete bleeding operation. Use Ford High Performance DOT 3 Motor Vehicle
Brake Fluid C6AZ-19542-AA or equivalent DOT 3 fluid meeting Ford specification ESA-M6C25-A for all brake applications. Never reuse brake fluid that has been drained from the hydraulic
system. Pressure bleeder tank should be charged with approximately 69-207 kPa (10-30 psi) of air pressure.
CAUTION: Never exceed 345 kPa (50 psi) pressure.
1. Clean all dirt from the brake master cylinder filler cap.
2. Remove brake master cylinder filler cap and fill brake master cylinder reservoir with specified brake fluid. Install pressure bleeder adapter tool to brake master cylinder reservoir and
attach bleeder tank hose to fitting on adapter. Follow manufacturer's instructions when installing adapter.
3. If all wheel locations are to be bled, start at the RH rear wheel and attach bleeder tube snugly around bleeder screw.
4. Open valve on bleeder tank to admit pressurized brake fluid to brake master cylinder reservoir.
5. Submerge free end of tube in container partially filled with clean brake fluid and loosen bleeder screw.
6. When air bubbles cease to appear in fluid at submerged end of bleeder tube, close bleeder screw and remove tube. Replace rubber dust cap on bleeder screw.
7. Repeat Steps 3 through 6 at LH front disc brake caliper (2B121).
8. Next, repeat Steps 4, 5 and 6, starting at LH rear wheel and ending at RH disc brake caliper (2B120).
9. When bleeding operation is completed, close bleeder tank valve and remove tank hose from adapter fitting.
10. After disc brake service, make sure disc brake pistons are returned to their normal positions and the brake shoe and lining assemblies are properly seated. This is accomplished by
applying brake pedal several times until normal pedal travel is established.
11. Remove the pressure bleeder adapter tool from brake master cylinder reservoir. Fill the brake master cylinder reservoir up to or within 3.0 mm (0.125 inch) of the MAX line on the
brake master cylinder reservoir. Install the brake master cylinder filler cap .
Anti-Lock Brake System Bleeding
NOTE: Add Ford High Performance DOT 3 Motor Vehicle Brake Fluid C6AZ-19542-AA or equivalent DOT 3 fluid meeting Ford specification ESA-M6C25-A as necessary
throughout this procedure.
1. Connect a clear waste line to the LH front bleeder screw.
2. Open the LH front bleeder screw.
3. NOTE: One cycle of the brake pedal is from the full upright position of the pedal, to full extension of the brake pedal, to the full upright position.
With the bleeder screw open, cycle the brake pedal 25-30 times or until no more air is seen in the waste line.
4. Close the LH front bleeder screw.
5. Disconnect the waste line from the LH front bleeder screw.
6. Repeat Steps 2 through 6 for the front right brake, rear left and rear right brakes.
7. NOTE: The engine must be running to provide battery positive voltage (B+) to the ABS module.
Start the engine.
8. Depress the brake pedal to half of the full extension position.
9. NOTE: Performing the NGS program routine drives entrapped air from the otherwise inaccessible lower sections of the ABS valve into the upper sections (accessible by
bleeding at the brakes). Subsequent bleeding removes the air from the system.
Perform NGS program procedure for ABS service bleed.
Attach the Rotunda New Generation Star (NGS) Tester 007-00500 according to manufacturer's instructions and follow the menus and prompts.
From the "DDS Functions" menu, chose "4-WABS."
From the 4-WABS menu, choose "Function Tests."
From the Function Test menu, choose "Bleed Procedure" and follow the prompts.
10. NOTE: One conventional pressure bleed cycle consists of advancing the brake pedal to its extended position, opening the bleeder screw, allowing fluid to be released
into the waste containers, closing the wheel cylinder bleeder screw (2208) and releasing the brake pedal to its full upright position.
Perform a minimum of 7 conventional pressure bleed cycles on the LH and RH front brakes.
11. Repeat Steps 9 and 10 two times. However, on the last bleed cycle, make sure to bleed the rear brakes to make sure all air is removed.
--------------------
Ford Windstar ABS Brake Bleeding
Haynes manual procedure is as follows: ---
1. Empty the master cylinder
2. Refill with new fluid
3. Go to the farthest wheel cylinder (Right Rear)
4. Have helper push brake pedal and hold
5. Open valve
6. Close valve
7. Repeat steps 4-6 until clear
8. Refill master and do left front, left rear and then left front
It then goes on to talk about ABS equipped vehicles and it says to:
1. Start at Front Left
2. Open valve
3. Have helper pump 25 times until no air comes out
4. Close valve
But this procedure is bit confusing.----------
YOU can follow this procedure:---
For brake bleeding in general on vehicles without ABS, the order is:
·Master cylinder
·Left Front
·Right Front
·Left Rear
·Right Rear
The theory is that you are pushing any air bubbles rearward and by following the natural path the air wants to go, you will get all the air out.
On ABS equipped vehicles, since there are some that are required to be vacuum bled, I bleed all ABS vehicles with a vacuum bleeder. This also has the advantage of being a one man job, no helper is needed to pump the brake pedal.
In the ABS brake bleeding procedure the Haynes Manual gives you, they left out two important pieces of information. Well, here is the procedure from the Ford Manual.
Note: This procedure only needs to be performed if the 4-Wheel anti-lock brake (4WABS) Hydraulic Control Unit (HCU) has been installed new. (First piece of missing information.)
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.
1. Connect a clear drain tube to the RH rear bleeder screw and the other end in a container partially filled with recommended brake fluid. (Second piece of missing information.)
2. Have an assistant pump the brake pedal and then hold firm pressure on the brake pedal.
3. Loosen the RH 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 Steps 2 - 5 for the LH rear bleeder screw, the RH front bleeder screw and the LH front bleeder screw, in that order.
7. Repeat the conventional bleed procedure as outlined in Steps 2 through 6.
If you want to vacuum bleed the brakes, you can get a Mighty-Vac kit that has the brake bleeding attachments included.
The bottle they give you is kind of small so I made a larger one from a one gallon pickle bottle. I drilled two holes in the cap and soldered a three inch piece of metal tubing, leaving an inch above the cap, in one hole and an eight inch piece of tubing, or whatever length you need to get within one inch of the bottom, in the other. Again leaving one inch above the cap.
If you want to get fancy, you can use two long pieces and bleed both frons or both rears at the same time.
Hook your hand vacuum pump to the short tube and the hose from the bleeder to the long tube. Then just pump away until you get clear brake fluid coming out.
No comments:
Post a Comment