Announcement

Collapse
No announcement yet.

Brake troubles

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Brake troubles

    Okay, so when I did my turbo-job I went ahead and used the brakes off of the SS parts car. I've bled the them, even had a local shop bleed them, but they are still mushy has i'll get out. The pedal doesn't go all the way to the floor, but nearly does. It feels like they haven't been bled, but they have been extensively. The pedal comes up when pumped, and the booster system seams to work fine. The lines were never removed at the master, and i'm using the NA master that worked fine before. Are the MCs different for the dual piston calipers? Anybody know what the dea is here? The brakes are stopping me, but they make me nervous...

    The pedal doesn't seam to sink to the floor slowly as pressure is applied, and there is no fluid loss. I guess it's a bad MC? It just seams odd it goes bad all at once out of nowhere...
    My beloved Z:1987 2+2 NA2T w/30a swap.
    My black sheep: 88ss parts car (pretty much stripped and gone)
    207k miles and counting. Turbo'd since 155k.

  • #2
    Is it Low but firm when it is low? My trans am was this way. But this was probably due to the drums in the back. Are your rotors warped?

    Terrible idea putting those wheels on...

    Comment


    • #3
      pedal feels spongy, but it gets firm just before the bottom. I end up pumping them once just to get it a little farther from the bottom. Rotors are far better now than my NA rotors were. No more steering wheel shimmy or pulsating. Rotors seam fine, much better than before.
      My beloved Z:1987 2+2 NA2T w/30a swap.
      My black sheep: 88ss parts car (pretty much stripped and gone)
      207k miles and counting. Turbo'd since 155k.

      Comment


      • #4
        Sounds to me like you have some air in the system still. Sometimes it can be a pain to get them bleed out well and get the pedal nice and hard.

        If you havent tried a vacuum bleeder I would suggest it. $25-30 at a local parts store.

        I typically use the vacuum bleeder on all 4 and then the old pump and hold method if I have opened up the lines in several places in the course of whatever work I was doing. It usually works pretty well. However I have had to come back later and bleed them again. Some of those air bubbles can be pesky.
        Just stand back and throw money.
        Performance costs money.
        Reliable performance costs more.

        Comment


        • #5
          I think my brother has one of those (or the hanger he works in has one). Maybe i'll give that a shot. Whatever the deal it it's bugging me a lot.
          My beloved Z:1987 2+2 NA2T w/30a swap.
          My black sheep: 88ss parts car (pretty much stripped and gone)
          207k miles and counting. Turbo'd since 155k.

          Comment


          • #6
            Az4u2c wrote: I think my brother has one of those (or the hanger he works in has one). Maybe i'll give that a shot. Whatever the deal it it's bugging me a lot.
            I have the same problem, I have even replaced the master cylinder and put two quarts through the lines with no progress.

            Getting on my nerves too. I'm debating on replacing the rubber lines with SS braided and doing TT calipers and a TT master cylinder, and then bleeding the crap out of them again. If that doesnt do it im putting air brakes (huge fold out wings) on the car! :shock:
            85 Z31 6.0 LSX turbo 766whp/792wtq
            04 GTO, LS6, big cam, porting, N20... underway for summertime daily driver.

            Comment


            • #7
              Apply the E-brake until the brakes just start to catch, and then push the brake pedal to see if they are firm.
              With my car the pistons in the rear calipers aren't adjusting to keep the slack out as the pads wear down. I realy dont know if they should,
              but I assume they should. You have to turn them so they retract to put new pads on.........
              If that is the case you could turn the pistons enough to extract them
              enough to take out the slack, and restore a firm pedal.
              imagination is a virtue

              Comment


              • #8
                ^hmm, never tried that intentionally but I think it makes sense.

                Satan/ Ax4u2c- bleading brakes can be a pain in the rear after you have broken more than a couple fittings for any amount of time.

                This is very unorthodox but on my 84 last year I bleed the living crap out of them after I did all my suspension work. I didn't like the feel of the pedal. My solution was to use the pump and hold method right at the master cylinder after I had gone through all 4 wheels and a couple other fittings between the wheels and the master cylinder. Wherever that air was, it finally got out and the brakes were pure sex. Stiff as a rock.

                Unfortunately I will probably have to do it again on my 85 since the pedal seems a bit soft still after pumping/pulling a ton of fluid through the system from all wheels already. I like brakes that are very stiff and don't leave me any question as to their response. :shock:
                Just stand back and throw money.
                Performance costs money.
                Reliable performance costs more.

                Comment


                • #9
                  Az4u2c wrote: Okay, so when I did my turbo-job I went ahead and used the brakes off of the SS parts car. I've bled the them, even had a local shop bleed them, but they are still mushy has i'll get out. The pedal doesn't go all the way to the floor, but nearly does. It feels like they haven't been bled, but they have been extensively. The pedal comes up when pumped, and the booster system seams to work fine. The lines were never removed at the master, and i'm using the NA master that worked fine before. Are the MCs different for the dual piston calipers? Anybody know what the dea is here? The brakes are stopping me, but they make me nervous...

                  The pedal doesn't seam to sink to the floor slowly as pressure is applied, and there is no fluid loss. I guess it's a bad MC? It just seams odd it goes bad all at once out of nowhere...
                  --SEEM-- not "seam", and what does "has i'll get out" mean?

                  Comment


                  • #10
                    best way to test the master cylinder is what I call a crimp down test. Take a piece of cardboard and fold it over the rubber part of the brake lines. Then lock a decent set of vice grips over each one. If you're sure that there is no air in the brake lines, the pedal should have NO play whatsoever. If it does, double check to make sure there is no air in the lines, if you're POSITIVE that there is NO air in the lines, replace the master cylinder, it's leaky.
                    Funny stories!

                    Comment

                    Working...
                    X