My brake pedal goes all the way to the floor there is no any brake oil leak i replace the brake master cylinder i bleed the system but still the same what is the correct procedure to bleed brake system ford expedition 1997

If it goes to the floor and no brake warning lites or anything comes up on the dash, check the brake booster--engine vacuum and vacuum to the booster. Just my opinion. The master cylinder usually bolts to the booster.

Not bleed properly
or you have a rusted out line (leak)

There is NO Procedure-- that when driving a
vehicle or bleeding brakes,do you ever pump them

Did you get a good bleed with fluid coming out at all four wheels? If they bled good, and the pedal still goes to the floor, you need to check the brake master cylinder-it is probably shot with an internal leak. An internal leak will not let fluid pressure build up, so no brakes.

Did you keep the brake fluid reservoir from going dry while bleeding? If it went real low, air might have got back into the lines.

It is not uncommon when bleeding brakes on an older vehicle for the master cylinder to suddenly develop an internal leak and require replacement . Here's why: pushing the pedal all the way to the floor causes the master's piston to push in farther than ever before. The rubber cups then travel over a section of the cylinder not usually touched by the cups-old fluid can develop a crud there and when the piston pushes over it, the cups can get ruined. To avoid this when bleeding brakes, put a short piece of 2X4 wood block under the pedal. Then the pedal will not extend the master's piston beyond it's normal travel. Of course on a new master cylinder, you do not have to do this. A new master cylinder does require bench bleeding before installing, however, to ensure no air pockets develop from there.

Did the pedal go to the floor beforehand? Was the master cylinder leaking, and did you bleed it properly? If the master cylinder was not leaking, check your brake lines going to the rear wheels.

well, check the brake lines for leakage after adding brake fluid to the full mark. If the brake pedal goes all the way to the floor, it's likely there is a leak somewhere after the master cylinder. If the pedal gets hard after adding fluid, and pumping it several times with the car off, then the master cylinder is still ok.

If air has gotten into the master cylinder, it may have to be bled out on a bench, or using a scanner if that's the way your vehicle is.

Bleeding the Brake System (ABS) Auto Bleed Procedure NOTE: Perform a manual bleeding procedure. If the brake pedal height and firmness results are not achieved, perform the auto bleed procedure below.
NOTE: Perform this procedure when replacing the brake pressure modulator valve or electro-hydraulic control unit.

1. Perform the manual brake bleeding procedure. Refer to Bleeding the Brake System (non-ABS).
2. Check the master cylinder fluid level often to prevent running the system dry.
3. Press the brake pedal firmly and run the Scan Tool Automated Bleed Procedure (for Gas engines) once, or the Function Test (for Diesel engines) four times. Make sure to release the brake pedal between each test.
4. Perform the manual bleed procedure again. This should remove the remaining air from the brake system.
5. Bleed the system as many times as needed to obtain the appropriate feel of the brake pedal.

The liquids does not compress, so there is no reason for the brake pedal to go to the floor. If you have no brake pressure, after bleeding the system, then the master cylinder is wasted. The brake master cylinder leak might be Internal, or External. Check around the master cylinder for any external leak. The break fluid is an excellent paint eater, so clean any leak before you remove the Master Cylinder. The new Master Cylinder needs a bench bleeding process, before installed in your car.

possible leak in brake system. if not then you have a bad master cylinder. have to replace it.

You changed the master cylinder and vacuum booster and have no leaks anywhere, but did you bleed the entire brake system after you did this work? A little bit of air in any of the lines will make the brakes ineffective.

When you fixed the brakes, did you take the lid off the master cylinder. I just wonder if you spilled out your brake fluid. The only reason the pedal should go to the floor is if the brake fluid is gone or the master cylinder is not working. Check the fuse. Check the brake fluid level. The pedal only goes to the floor if there is no back pressure in the lines between the master cylinder the lines to the brake pistion on the calipers. Please give me a good ratin and keep me informed.

you will have to bleed them again. air must have gotten in while (nipple) was still loose.