pump brakes and get a hard pedal but as soon as you release the pedal, the pedal goes to the floor

Asked by tedtulare May 10, 2014 at 08:39 PM about the 1968 Mercury Cougar

Question type: Maintenance & Repair

Had a leaky proportioning valve. Replaced it, distribution block, master cylinder and all
front lines. Pre-bled the master cylinder and Bled brakes several but as soon as you
release the pedal, the pedal goes to the floor. All this done with the engine not running.
Does anyone have a suggestion on what is wrong?

5 Answers

255

Does it do it with the engine running? If not, you could have a vacuum leak maybe in the brake booster.

1 people found this helpful.
14,745

That valve should have a reset button on it at the top so try resetting it. Alos, open up the front brake bleeders and let them run for a few minutes keeping the master cylinder reservoir full while doing it. Good Luck, Kenny/MrBlueOval

605

sounds like you got a bad master cylinder, don't buy a rebuilt master cylinder, buy a brand new one, better be safe then sorry, and if their is a leak in the booster you will here the air escaping and the car will tremor when you push on the brake, My proportioning valve has been rebuilt and is original but I don't have a reset button on the valve.

1 people found this helpful.
605

did you bleed all 4 wheels,start from the back passenger side bleed it 3 times, then the back passenger driver side bleed it 3 times, next is the front start at the passenger side bleed it 3 times then go to the front driver side bleed it 3 times,

1 people found this helpful.

Your Answer:

Cougar

Looking for a Used Cougar in your area?

CarGurus has 3 nationwide Cougar listings and the tools to find you a great deal.

Postal Code:

CarGurus Experts

  • #1
    lisagayle
    Reputation
    2,350
  • #2
    Jessica Cornelison
    Reputation
    640
  • #3
    dandyoun
    Reputation
    460
View All

Find great deals from top-rated dealers

Search

Related Models For Sale

Used Ford Mustang
58 Great Deals out of 1,366 listings starting at $4,995
Used Ford Thunderbird
28 listings starting at $14,888

Content submitted by Users is not endorsed by CarGurus, does not express the opinions of CarGurus, and should not be considered reviewed, screened, or approved by CarGurus. Please refer to CarGurus Terms of Use. Content will be removed if CarGurus becomes aware that it violates our policies.