Brake pedal goes to floor with no pressure

CODY STONE

MEMBER
1969 CHEVROLET NOVA
7.4L
V8
2WD
AUTOMATIC
3,000 MILES

My car listed above had all four drum brakes and we replaced them with all brand new disc brakes. We have bled the brakes literally over 50 times at least and the brake pedal still goes to the floor. We have a brand new master cylinder and brake booster so it makes no sense that we don't have any pressure to the brakes.

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

The only way you are going to have a pedal go to the floor is due to loosing pressure via a leak either internally or externally. I assume you have not found any external leaks which means we are allowing pressure to bleed off. When you bleed the brakes are you getting fluid to squirt out at each caliper?

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

What I suspect we are going to have to do is cap off each port from the master cylinder and operated the pedal. With no brakes lines you should have a firm pedal. If not then the master cylinder is the issue.

If you do have a firm pedal then add in one port at a time until you find it dropping to the floor again. Once it does you know which leg of the system is the issue.

Let me know if you have questions. Thanks