How do I and what tools

Discussion in 'Touring Models' started by Fourdogs, Jun 30, 2010.

  1. Fourdogs

    Fourdogs Junior Member

    805
    28
    3
    I have to replace my rear brake light switch. What tools (size socket) are needed. Also will I loose much brake fluid when replacing?
     
  2. glider

    glider Veteran Member

    25,464
    108
    44
    Not a difficult thing to do. Some are hex head and others are like an oil pressure sending switch so you need a different socket.

    You may have to bleed because there is no way to swap them without introducing air into the system. As long as the cover is on the master cylinder, you'll only get a few drops out of it.
     
  3. Breeze3at

    Breeze3at Well-Known Member

    4,645
    83
    124
    I just measured my '07 FLHTC switch, it's 17 mm hex. My '92 Dyna switch is the odd shape, a 26mm or 1" SIX point socket fits it. A deep well works best.
    Glider covered you on brake fluid. I also fill up the new switch (few drops really), just to minimize the air factor. Most runs out, but it makes me feel like I tried.
     
  4. HKSkully

    HKSkully Member

    27
    11
    0
    Hint

    If you depress the brake pedal slightly, the master cyclinder port will be covered up by the the piston movement and you will only loose very little fluid. Just be carefull because when you break open the hydraulic system, it will initially be under a slight pressure. This will keep your master cyclinder from gravity bleeding dry.
     
  5. Hoople

    Hoople Account Removed

    7,198
    0
    34
    Re: Hint

    I may be wrong but I would think having the master cylinder gravity drain would allow less of a chance of air getting into the system while you swap out the switch. I would actually have a helper push on the pedal very slowly to create positive fluid flow thereby preventing air from being pulled in.

    Yes, no , maybe?
     
  6. Bud White

    Bud White Well-Known Member Retired Moderators

    3,270
    48
    2
    Re: Hint

    either way your gonna have to bleed its gonna get some air in it
     
  7. glider

    glider Veteran Member

    25,464
    108
    44
    Re: Hint

    Seems logical to me. :D
     
  8. Jack Klarich

    Jack Klarich Expert Member

    18,544
    153
    399
    Re: Hint

    Very good way to keep air out of system, have used this way before, steady pressure not too much:s
     
  9. rlb333333

    rlb333333 Member

    15
    0
    0
    you'll need a sendingunit socket and rachet,,hex wrenches,,you wont loose much brk fluid ,,but will need to bleed system,,i recomend puting a length of vacuum line in a plastic bottle w/brk fluid in the bottle and bleed system,keep resivour topped off at all times,,piece of cake ..or if you have a reverse bleeder ,,even easier..

    good luck
     
  10. Dr.Evil

    Dr.Evil Junior Member

    694
    0
    5
    It's not a bad job to bleed the brakes, not like a car. Only a couple of oz of fluid and you will have nice new fluid in the system. Did it myself, and I am only 5'6"