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    Unable to bleed rear brakes. Brake issues

    I am trying to chase a brake problem. I have replaced the master cylinder, proportioning valve/bias valve, rear t junction above the subframe. I have bench bled the master cylinder and tried to bleed all 4 calipers using the following methods.

    I have tried the traditional pedal pump, pushing fluid into the bleeder screws screws and out of the reservoir, gravity bleed, and last vacuum pump. The fluid seems to just trickle or drip out of both rear bleeder screws.

    So far the front are perfect but I can't seem to get any compression on the rear. I have dropped more money than I need to trying to find this problem

    I am running out ideas and patience. Any help would be appreciated.

    #2
    Either the bleeder screws are clogged or the rear flexible lines are old and swollen and need replacement.

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      #3
      could be your abs pump is bad too
      sigpic
      Gigitty Gigitty!!!!

      88 cabrio becoming alpina b6 3.5s transplanted s62
      92 Mtech 2 cabrio alpinweiss 770 code
      88 325ix coupe manual lachsilber/cardinal
      88 325ix coupe manual diamondschwartz/natur
      87 e30 m3 for parts lachsilber/cardinal(serial number 7)
      12 135i M sport cabrio grey/black

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        #4
        Did you remember to bench bleed the master cylinder before installing?

        I had the same issue after redoing my entire brake system. I could bleed the fronts no problem but couldn't get anything out of the rears.

        Really simple to do too. Remove it with the reservoir still attached. Stick some hose in the outlets rerouted into a full reservoir (to prevent air being sucked backwards) and pump it until no more bubbles appear.

        Excuse my dirty mess, but this is what mine looked like:

        P.O.S 1989 325is - aka Project Sh*tbox

        Project Shitbox - Restomod and other stuff - soon to be 328is

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          #5
          One time this merc came into my shop and no one could bleed the front brakes. Previous mechanic replaced literally everything. Turned out he installed the calipers on the wrong side, so the bleeder was at the bottom of the caliper. Fluid came out and all the air was stuck up top. Probably not your problem, but hey, you never know.
          Originally posted by wholepailofwater
          Q
          :devil:


          WTB: Dove Grey e36 Front Door Panels (2 door)

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            #6
            Hey guys sorry for the late reply.
            Since the post was made I have rebuilt the rear calipers and realized they was alot of corrosion/gunk inside. Sadly this did not fix the issues. I am able to vacuum clean/clear fluid out with zero air in all of the lines. The pedal now has zero resistance when the car is on. Pedal literally drops to the floor when pressed.

            1. I have bench bled the MC but I will be doing this again because I feel like I might have screwed this up somehow since this was the the first time I ever bench bled anything.
            2. I removed the rear bleeder screws and cleaned them with brake cleaners. No signs of rust or corrosion.
            3. Calipers are installed the correct way with the screws in the upward direction.
            4. Lastly I am hoping the abs pump has not gone out. I'll will consider this as last resort.

            What is the likelihood of of the problem lying is a bad MC or faulty brake booster?

            Comment


              #7
              Originally posted by MrBurgundy View Post
              One time this merc came into my shop and no one could bleed the front brakes. Previous mechanic replaced literally everything. Turned out he installed the calipers on the wrong side, so the bleeder was at the bottom of the caliper. Fluid came out and all the air was stuck up top. Probably not your problem, but hey, you never know.
              Is that mechanic still working at your place? How long til someone realized that those things at the bottom were the bleeder screw? ;-)
              Brake harder. Go faster. No shit.

              massivebrakes.com

              http://www.facebook.com/pages/Massiv...78417442267056





              Comment


                #8
                Originally posted by Massive Lee View Post
                Is that mechanic still working at your place? How long til someone realized that those things at the bottom were the bleeder screw? ;-)


                It came from another shop


                Sent from my iPhone using Tapatalk
                Originally posted by wholepailofwater
                Q
                :devil:


                WTB: Dove Grey e36 Front Door Panels (2 door)

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                  #9
                  I had this problem, and it turned out to be the ABS pump. I replaced all of the rear brake lines the, when I went to bleed them, no fluid would come out. The front brakes would bleed, but not the rear. Anyway, the ABS pump was bad. I have used one from eBay on order and believe this will solve my problem.
                  1988 Alpinweiss 325i Convertible

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