Brakes keep failing, master cylinder has been replaced three times in a year

2012 HONDA RIDGELINE
85,000 MILES • 6 CYL • AUTOMATIC
Avatar
KEAB
  • MEMBER
  • 2 POSTS
I own the vehicle listed above RTS model. In the past year the master cylinder has been replaced 3 times, each time brakes are bled. Each time within 2 weeks to a month the brake pedal again softens and goes to the floor. I am not trying to play the old lady card, but I am 60 and I drive around my granddaughters. I am desperate to find an answer, I find it hard to believe a master cylinder would keep going bad and have the same issue 3 times in a year.
Dec 30, 2019 at 3:07 PM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Hi,

That is odd. When the part is replaced, is it with a new master cylinder or is it a re-manufactured part? The idea that it has happened this many times leads me to believe it's the part. If it was not installed correctly, one would think it wouldn't work correctly right away.

Let me know.
Joe
Dec 31, 2019 at 11:18 PM
Avatar
KEAB
  • MEMBER
  • 2 POSTS
Original OEM replaced with Honda part each time, (Bap Geon), who specializes in import auto parts. If dealer was purchasing, then it would come from Auto Zone, Advance, O'Reillys , etc whoever is closest. To my knowledge nothing else has been checked, ie brake lines/hoses, ABS, and a slew of other things. Now claiming possible brake booster. Thinking why didn't you check that a few master cylinders ago?? Find it very hard to believe that 3 master cylinders are all bad within a 12 month period. Also given the fact that after each change within 2-3 weeks the problem presents itself again. If air is getting in the brake line, I'd like to know how. Fluid is full all the time. If I pump brakes that helps, but when I sit at stop light, they drift down to floor, I have to pump them to bring them back.
Jan 1, 2020 at 3:57 AM
Advertisement
Avatar
JACOBANDNICKOLAS
  • CERTIFIED EXPERT
  • 110,175 POSTS
Hi,

I have to be honest, the idea that the pedal sinks to the floor when you hold pressure on it indicated the fluid is bypassing the plunger in the master cylinder. I'm not sure how the booster would be causing that issue. Maybe you should suggest a different brand master cylinder.

Since it fixes the problem for a couple weeks and then starts again, I feel the MC's they have been getting are bad. Even though one would think an OEM part would be best, they can have bad ones as well. Also, once the system is sealed and working, there is no way air is getting into the system unless you see a leak at some point. Does the brake fluid remain full regardless if the issue?

The master cylinder on this vehicle is a typical design. There really isn't anything different or out of the ordinary. I suspect they have been getting a bad batch of parts. Other than that, check to see if you have one of the rubber brake hoses expanding when the pedal goes to the floor. Have a helper watch them as you press the brake.

Take a look through this link and see if anything is helpful:

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

Let me know.
Joe
Jan 1, 2020 at 5:06 PM