Need some help with a soft brake pedal

Discussion in 'All Non-S197 Media' started by Cole, Jan 8, 2019.

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  1. Cole

    Cole Junior Member

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    Hey guys! I’m working on a 94 Honda Civic Del sol, and I need some help.

    I tried jumping on a Honda forum for the sake of relevancy, but everyone there seems to insist that I just don’t know how to bleed brakes. Here’s the situation:

    The problem it was having is one day the brake light came on, due to low fluid. One week later the brake pedal started going all the way to the floor, and the brakes were barely slowing the car down. Very dangerous and scary to drive.

    After visual inspection of the brake system, I discovered a leaking proportioning valve. I replaced it (big pita) and bled the brakes.

    Problem is the pedal still goes all the way to the floor, and the car barely stops. I visually inspected all of the other lines and components, and I can not seem to find any leaks. Also the brake fluid level is not changing (indicating no more leak, am I right?)

    Anyone know what can be causing this? The car has a brand new master cylinder, a new used prop valve that is not leaking, no leaking lines and no leaking calipers.

    If anyone can offer any ideas on this it would be greatly appreciate do.

    Happy new year.

    -Cole
     
  2. Dino Dino Bambino

    Dino Dino Bambino I have a red car

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    Sounds like the only thing left to replace is the brake servo. When it goes bad, it can cause the exact symptoms you've described. You might want to first check that there isn't a leak in the vacuum line coming from the intake manifold to the servo.
     
  3. Dad

    Dad forum member

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    You might have to take it to a shop and have the lines bled mechanically rather than the old school method.
     
  4. Cole

    Cole Junior Member

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    The brake booster holds vacuum. I’m afraid to start throwing money at this thing to have it not work but I guess that’s the point I’ve gotten to right? Thinking of just replacing the booster and the master cylinder at the same time. Hate this car.
     
  5. Dino Dino Bambino

    Dino Dino Bambino I have a red car

    Age:
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    You might be able to find a good used brake booster in eBay or in a junkyard. Given that all the brake lines, MC, and proportioning valve are leak free, the servo may be the only thing left.
    Just double check that the lines are properly bled, that the pads aren't worn, and that none of the calipers are sticking before you replace the servo.
     
  6. 86GT351

    86GT351 forum member

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    Simple inspection. In Bolt the Master Cylinder from the Booster and pull it away slightly. See if any fluid pours out. You could have an internal bypass inside the Master Cylinder. This fluid fills the Booster and causes the Diaphram inside to go bad. Repair is to replace both the Booster and Master.
     
  7. Cole

    Cole Junior Member

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    The master cylinder was replaced by the previous owner less than 12 months ago, however when I look at the booster with the master cylinder off it is very obvious that brake fluid was leaking out the back of the old master cylinder. You can see where the brake fluid ate away at the paint/coating that’s on the booster.

    You guys think this previous leak could be what led to the booster failing?

    Either way I have a new booster, I have to wait for the rain to stop and I will install it.
     
  8. Dino Dino Bambino

    Dino Dino Bambino I have a red car

    Age:
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    388
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    Yes, almost certainly.
     
  9. 86GT351

    86GT351 forum member

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    That can definitely cause a concern