Why does my brake pedal have to much travel?

anual Bleeding
The primary and secondary (front and rear) hydraulic brake systems are individual systems and are bled separately. Bleed the longest line first on the individual system being serviced. During the complete bleeding operation, DO NOT allow the brake master cylinder reservoir (2K478) to run dry. Keep the master cylinder reservoirs filled with High Performance DOT-3 Brake Fluid C6AZ-19542-AA or DOT-3 equivalent meeting Ford specification ESA-M6C25-A. Never reuse brake fluid that has been drained from the hydraulic system or has been allowed to stand in an open container for an extended period of time.
NOTE: Non-ABS vehicles have the brake master cylinder (2140) mounted at an angle to the horizontal, bleeding may be better performed if the vehicle is positioned so that the brake master cylinder is horizontal.

1. To bleed the brake system, position a suitable box wrench on the bleeder fitting on the brake wheel cylinder. Attach a rubber drain tube to the bleeder fitting. The end of the tube should fit snugly around the bleeder fitting.

1. Submerge the free end of the tube in a container partially filled with clean brake fluid, and loosen the bleeder fitting approximately three-quarters of a turn.

1. Have an assistant push the brake pedal (2455) down slowly through its full travel. Close the bleeder fitting, then return the brake pedal to full-release position. Repeat this operation until air bubbles cease to appear at the submerged end of the bleeder tube.

1. When the fluid is completely free of air bubbles, secure the bleeder fitting and remove the bleeder tube.

1. Repeat this procedure at the brake wheel cylinder on the opposite side. Refill the brake master cylinder reservoir after each wheel cylinder is bled, and install the master cylinder cap and gasket. Ensure the diaphragm-type gasket is properly positioned in the master cylinder cap. When the bleeding operation is completed, the fluid level should be at the MAX line to 4.0 mm (0.16 inch) below.

1. If the primary (front brake) system is to be bled, repeat Steps 2 through 5 at the right front brake caliper and ending at the left front brake caliper. Bleed the brake master cylinder at the bleed screw after all calipers are bled.

1. After disc brake service, ensure that the disc brake pistons are returned to their normal positions and the shoe and lining assemblies are properly seated. This is accomplished by depressing the brake pedal several times until normal pedal travel is established.

1. Check pedal feel. If brake pedal feels "spongy" repeat bleed procedure, or use the Vacuum method as outlined in Section 06-09, but bleed both rear calipers first.

You can also pressure bleed it. If the abs module needs to be bleed, that requires a special tool. If you have already tried the procedure posted and it didn't work, I'm not sure what next?

If the master cylinder is replaced, care must be taken to prime the new master cylinder by removing all of the air and completely filling it with brake fluid. The spongy feeling is air that is still in the circuits. You will need to bleed the back brakes as well as the front ones again. The order that you bled them seems correct, but perhaps there remained some air in the main trunk lines.

For the best results 2 people are needed. Start at the further distance wheel cylinder and bleed at least three (3) master cylinder reservoir volumes of fluid (back brakes). Bleed the fluid with use of a piece of tubing attached to the bleed port that is long enough to reach almost to the bottom of a long neck or tall clear jar (clear drink bottle works well). When the bleeding begins, after one or two brake pedal pushes, make sure that the end of the tubing is below the surface of the fluid and keep it under. It best to have a clear bleed line (to observe air). Keep pumping the brake pedal while being careful to not completely empty the master cylinder reservoir (leave 1/4 full always). Repeat the same technique for each wheel cylinder with at least two (2) reservoirs full for front brakes. Partially close the bleed ports when almost finished (at least 5 pedal strokes without exit of any air). Completely close the ports during the down stroke of the brake pedal, with the tubing still attached. Be sure each bleed port is closed snuggly.
Most of the brake fluid can be reused, but not the darker portion at the bottom of the jar.

Hi, it may not be the master cylinder but a leak in the piping or other brake parts. The system was bled to get all the air out when the new cylinder was fitted and it sounds like you are getting air back into the system again that will cause the brakes not to work .Some times it can be caused by a perforated brake pipe due to rust.

Sounds like a bad brake booster.. It's the large can behind the master cylinder. The fact you have a hard pedal with engine off is the key here.

Still air in system, sounds like the master cylinder has ran dry during the bleeding process, pumping more air into system. The lines running to the rear brakes are long, so you must bleed the fluid out the bleed screw in the rear 10+ times each side. Bleed, bleed, and bleed some more, keep bleeding untill that pedal feels good.

Hello Patricia,

Have you checked the master brake cylinder reservoir for brake fluid loss?

I don't suspect the master cylinder as you have replaced it... but am more suspect of a leaking brake line or fitting which should have
been discovered when you had the system bled.

The only time I ever had a rear brake problem with a 2500 series Chevrolet was due to seized rear brake caliper guide pins...as your calipers are also new that is not your problem.

If your brake pedal feels spongy and travels to the floor board you have air in the system, a brake fluid leak or a failure in the power steering system, such as a broken hose, broken power steering pump drive belt, or failed pump, would result in a loss of pressure to both the hydro-boost and steering.

Find more information here:

. Hydro Boost Power Assist Systems Operation Diagnosis and Repair

PRESSURE BLEEDING

MANUAL BLEEDING

Print
For vehicles equipped with an Anti-lock Brake System (ABS), please refer to the ABS bleeding procedure at the end of this section.
The purpose of bleeding the brakes is to expel air trapped in the hydraulic system. The system must be bled whenever the pedal feels spongy, indicating that compressible air has entered the system. It must also be bled whenever the system has been opened or repaired. If you are not using a pressure bleeder, you will need a helper for this job.

WARNING Never reuse brake fluid which has been bled from the brake system.

MASTER CYLINDER

See Figure 1
If the master cylinder is off the vehicle, it can be bench bled.

1. Secure the master cylinder in a bench vise.
2. Connect 2 short pieces of brake line to the outlet fittings, bend them until the free end is below the fluid level in the master cylinder reservoirs.
3. Fill the reservoir with fresh DOT 3 type brake fluid.
4. Using a wooden dowel, or equivalent, pump the piston slowly several times until no more air bubbles appear in the reservoirs.

Fig. Fig. 1: Attach bleeding tubes to the master cylinder and position them as shown

1. Disconnect the 2 short lines, refill the master cylinder and securely install the cylinder cap.
2. If the master cylinder is on the vehicle, it can still be bled, using a flare nut wrench.
3. Open the brake lines slightly with the flare nut wrench, while pressure is applied to the brake pedal by a helper inside the vehicle.
4. Be sure to tighten the line before the brake pedal is released.
5. Repeat the process with both lines until no air bubbles come out.
6. Bleed the complete brake system, if necessary.

If the master cylinder has been thoroughly bled and filled to the proper level upon installation into the vehicle, it is not necessary to bleed the entire hydraulic system.

PRESSURE BLEEDING

When bleeding the brakes, air may be trapped in the brake lines or valves far upstream, as much as 10 feet from the bleeder screw. Therefore, it is very important to have a fast flow of a large volume of brake fluid when bleeding the brakes, to make sure all of the air is expelled from the system.
On Cirrus, Stratus, Sebring convertible and Breeze models, the following wheel sequence should be used to ensure that all the air is removed from the system:


Left rear wheel Right front wheel Right rear wheel Left front wheel
On Sebring coupe and Avenger models, the following wheel sequence should be used to ensure that all the air is removed from the system:


Right rear wheel Left front wheel Left rear wheel Right front wheel

1. You should use bleeder tank tool C-3496-B or equivalent, with the required adapter for the master cylinder reservoir to pressurize the hydraulic system for bleeding. Make sure to follow the manufacturer's directions for using a pressure bleeder.
2. Attach a clear plastic hose to the bleeder screw located at the right rear wheel, then place the hose into a clean jar that has enough fresh brake fluid to submerge the end of the hose.
3. Open the bleeder screw at least one full turn or more to get a steady stream of fluid.
4. After about 4-8 oz. of fluid has been bled through the brake system and an air-free flow is maintained in the hose and jar, close the bleeder screw.
5. Repeat the procedure at all the other remaining bleeder screws. Then, check the pedal for travel. If pedal travel is excessive or has not improved, enough fluid has not passed through the system to expel all of the trapped air. Be sure to monitor the fluid level in the pressure bleeder. It must stay at the proper level so air will not be allowed to re-enter the brake system through the master cylinder reservoir.
6. Once the bleeding procedure is complete, remove the pressure bleeding equipment from the master cylinder.

MANUAL BLEEDING

See Figure 2
Proper manual bleeding of the hydraulic brake system will require the use of an assistant.
On Cirrus, Stratus, Sebring convertible and Breeze models, the following wheel sequence should be used to ensure that all the air is removed from the system:


Left rear wheel Right front wheel Right rear wheel Left front wheel
On Sebring coupe and Avenger models, the following wheel sequence should be used to ensure that all the air is removed from the system:


Right rear wheel Left front wheel Left rear wheel Right front wheel

Fig. Fig. 2: With a clear plastic hose in a container of clean brake fluid, open the bleeder screw at least one full turn

1. Attach a clear plastic hose to the bleeder screw located at the right rear wheel, then place the hose into a clean jar that has enough fresh brake fluid to submerge the end of the hose.
2. Have an assistant pump the brake pedal 3-4 times, and hold it down before the bleeder screw is opened.
3. Open the bleeder screw at least one full turn. When the bleeder screw opens, the brake pedal will drop.
4. Close the bleeder screw. Release the brake pedal only AFTER the bleeder screw is closed.
5. Repeat the procedure 4 or 5 times at each bleeder screw, then check the pedal for travel. If the pedal travel is not excessive, or has not been improved, enough fluid has not passed through the system to expel all of the trapped air. Make sure to watch the fluid level in the master cylinder reservoir. It must stay at the proper level so air will not re-enter the brake system.
6. Test drive the vehicle to be sure the brakes are operating correctly and that the pedal is solid.

Section 06-06: Hydraulic Brake System 1992 Festiva Workshop Manual GENERAL SERVICE OPERATIONS Manual Bleeding

1. Read Hydraulic System Bleeding General Information.

1. Clean all dirt from the master cylinder filler cap.

1. Fill the master cylinder with the specified brake fluid. During the bleeding operation do not allow the master cylinder to run dry.
   

1. If the master cylinder is known or suspected to contain air it must be bled before the wheel cylinders or calipers. To bleed the master cylinder, loosen the front line fitting and have an assistant push the brake pedal slowly through its full travel. While the assistant holds the pedal, tighten the brake line fitting. After the line fitting is tightened, the assistant may release the brake pedal. Repeat this procedure on the rear brake line. Repeat the entire process several times to ensure all air has been removed from the master cylinder.
   

1. Remove the bleeder screw cap from the appropriate rear wheel cylinder.

1. Position a box end wrench on the bleeder fitting.

1. Attach a rubber hose to the bleeder fitting. The hose has to fit snugly around the bleeder fitting.
   

1. Submerge the free end of the hose in a container partially filled with brake fluid.

1. Loosen the bleeder fitting approximately three quarters of a turn.

1. Have an assistant push the brake pedal slowly through its full travel and hold it there.

1. Close the bleeder fitting.

1. Have the assistant release the brake pedal.

1. Repeat Steps 9 through 12 until air bubbles cease to appear at the submerged end of the bleeder hose.

1. When the fluid entering the bottle is completely free of bubbles, tighten the bleeder screw, remove the bleeder hose, and install the bleeder screw cap.

1. Repeat Steps 5 through 14 at the appropriate diagonal front caliper.

1. Check the master cylinder fluid level. If necessary fill it to the correct level with the specified brake fluid.
   

1. Check pedal feel. If the pedal remains spongy, repeat the bleeding process or, if necessary, refer to Diagnosis and Testing in Section 06-00.

was the master cylinder a new one ??or a secondhand one

Check the rear brakes are not leaking, or have air in the fluid feed line.
If above OK, it's probably caused by a faulty master cylinder.
(To check :- Slacken off the master cyl feed to the front (then rear) brakes, and observe if any fluid is being delivered - if not it is definitely a master cyl problem).