I have changed my master cylinder brake pedal goes to the floor

Good morning,

If you are absolutely positive that there are no leaks and you still have a pedal that goes to the floor, I would still be looking at the master cylinder. A couple of questions for you.

1. Does this vehicle have ABS brakes?
2. Is the master cylinder that you installed a brand-new part or a rebuilt?
3. When the pedal does go to the floor, does it go rapidly with little or no resistance? or does it just creep slowly and eventually get to the floor?

Jon

My deacon is a diesel mechanic and he has been the one doing the work. He says no leaks and I brought it to Chabills for them to look at. They said no leaks.

1) Yes.
2) Brand new.
3) Rapidly, little resistance.

This can be caused by a seized caliper slide. Also, did you bench bleed the master before installing it? If not here is a guide to help explain how:

https://www.2carpros.com/articles/how-to-replace-a-brake-master-cylinder

This guide can help as well:

https://www.2carpros.com/articles/brake-pedal-goes-to-the-floor

Please run down this guide and report back.

Cheers, Ken

Yes, both master cylinders were bench bled properly.

This car has ABS yes? You will need to have a shop open the the ABS valves one at a time as they bleed the brakes. Air can be trapped inside the ABS unit. One thing you can try is use 4 vise grips and gently close off the brake flex lines to see if the pedal still goes to the floor. If it stays firm the problem is at the wheels if not the master/ABS is to blame. Please let know.