front brake bleeding problems...

Discussion in 'Touring Models' started by robertc500, Jul 30, 2011.

  1. robertc500

    robertc500 New Member

    I have a 2000 Road King that I recently took off a aftermarket chrome master cyclinder and replaced with oem. Bought a vacuum bleeder from harbor frieght. Went to flush and bleed brakes. Nothing was coming out when I released the bleeder screw. Some fluid would come out from the bottom of the screw but nothing through the vacuum. Lever still spongy. Haven't tried reverse bleeding because old fluid is still in the lines. Any help on how to flush and get pressure back on the lever. Really don't want to take it to a dealer and pay the 89 dollar labor rate for something I can do in my garage. Thanks.
  2. TripleJ

    TripleJ Senior Member

  3. dieselguy65

    dieselguy65 Account Removed

    a few wraps of teflon tape is needed on the threads of the bleeder. otherwise when you crack it lose your vac bleeder just draws air around threads and not drawing fluid into it. the tape will also be nice next time, because your bleeders will not be froze in place.
    1 person likes this.
  4. dbmg

    dbmg Guest

    1st try what dieselguy65 recommended. And is lid of master removed while using vacuum bleeder??? Did you bench bleed or bleed master on bike with line disconnected??? If master is not bled first you may never get fluid through system. You could try to just open both bleeders and let gravity bleed while keeping master filled...
  5. bc45

    bc45 Active Member

    If you just cracked bleeder open 1/4 to 1/2 turn and fluid is comming from the bottom of screw but through the end sounds like the bleeder might be plugged,Remove it and se if you can blow air through it.
  6. ironmark

    ironmark Junior Member

    I may just be a fluke but when I change to the chrome front brake reservoir I just did a gravity bleed. I filled the reservoir with brake fluid and then I cracked open the bleeder screw on the caliper and when I got a good steady flow from the bleeder screw I would close the bleeder screw. I did this one side at a time and I did the procedure until I was sure that there was no air in the lines. You have to make sure that the reservoir doesn't run out of brake fluid. It is not the proper way to bleed the front brakes but it worked for me and my front brakes work great.
  7. Jack Klarich

    Jack Klarich Guest

    Reverse Bleeder I have had good luck reverse bleeding. At work I have a special syringe for this, it no longer has a part number but I will try to track it and post it, I do remember where I bought it so that may help:s
  8. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

    Due to the angle of my handlebars the master cylinder banjo bolt is the highest point in the system so getting brake fluid to go down and the air to come out once the system has been drained is a bit of a pest
    i use a 150ml syringe that i fill with brake fluid connect to the bleeder by plastic see through pipe open the bleeder and depress the plunger on the syringe until resistance is felt
    this has pushed the brake fluid through the calliper and up the brake pipe pushing all the air ahead of it resistance is felt when the brake fluid gets to the small hole in the master cylinder
    close off the bleeder and top up the master cylinder remove syringe from plastic pipe direct pipe in a loop up then down and into a container apply pressure to brake leaver and open bleeder watch the fluid that goes into pipe close bleeder release pressure from brake leaver if there are any bubbles in the fluid repeat the apply pressure open bleeder close bleeder release pressure until no air in the fluid
    time taken start to finish 15 mins brake sorted

  9. R_W_B

    R_W_B Senior Member

    Hmmm I'm having problems getting my front brake to bleed out, as the OP did. I had my Mas Cyl off and back on. I have run a third of a bottle of DOT 4 fluid thru the Mas Cyl and thru the line and into a container (have plastic line over bleeder).

    I'm thinking I need to do this Master Bleed thing. What exactly is this, I take the line loose and then pump just the Mas Cyl ?
  10. fin_676

    fin_676 Experienced Member Staff Member Moderator Contributor

    If the fluid will flow through the system and out the bleeder then you are half way to being sorted
    The main problem with brakes bleeding is the way the bleeder seals
    the bottom part of the bleeder is cone shaped and it is what seals the bleeder
    with the bleeder open if you apply pressure to the brake leaver then fluid is pushed out the bleeder when the leaver is released air will be drawn back in through the bleeder
    if you use one of the 1 man bleeding systems that have a check valve then air is drawn in past the threads on the bleeder
    the only way that i know to work to get good solid brakes with no air is
    bleeder closed apply pressure to the brake leaver open bleeder let fluid come out close bleeder and release pressure from the bleeder
    provided the bleeder is at the highest point on the calliper all the air bubbles should come out with the fluid
    carry on with the apply pressure open then close and release till no more bubbles are in the fluid coming out the bleeder
    then you will be sorted