Bubbled Master Cylinder Paint

Discussion in 'General Harley Davidson Topic' started by FXDL4ME, Feb 22, 2019.

  1. FXDL4ME

    FXDL4ME Member

    Leaking brake fluid from the master cylinder is a common HD problem. The paint on my Street Glide master cylinder / brake lever mount point is bubbled and ugly. I'm pretty anal about my bike, and that irritates me to no end. Any ideas on covers or ways to fix the paint? What have you all done? Thanks!
  2. STEVE07

    STEVE07 Well-Known Member Staff Member Super Moderators

    When a tech or your self overtightens the two screws they will leak the top becomes distorted. New top and O-Ring will fix it. If the tech did it go after the dealership
    NCBILL likes this.
  3. FXDL4ME

    FXDL4ME Member

    Already replaced the cap and fixed the leak, just wondering how to clean up the damage to the paint.
  4. biscuit

    biscuit Junior Member

    Powder coating is a great way to do it. A lovely permanent coating. But you have to take the M/C off and deliver it to a powder coater.
    Have a look at the M/Cs that have been painted- the paint always comes off and then they look like they have a bad case of eczema.
    By the way, have you had your M/C cap off lately?
    And if you did, did you place it with the lid or top of the cap facing down , say on a shop towel or a piece of rag?
    And did you leave the rubber diaphragm in place whilst it was upside down?
    The most common cause of HD master cylinder weeps and seeps is taking the Cap and the diaphragm off the M/C and putting it down Cap side first, on a soft surface so it won’t be scratched.
    Brake fluid leaks from the diaphragm and gets under the plastic insert that maintains the shape of the diaphragm and supports it in position.
    When the Cap and diaphragm are put back on, the fluid that ended up between the Cap and the plastic insert just slowly leaks out. There’s no gasket to stop it as it leaks from ABOVE the gasket and makes a mess of your M/C
    FXDL4ME likes this.
  5. Breeze3at

    Breeze3at Experienced Member

    I fix my master cyl. bubbled paint by wire brushing (small toothbrush type), clean well with rubbing alcohol, then touching up with a small brush and Rust Oleum Satin Black. Not perfect, but pretty much unnoticeable and good enough for me.
    FXDL4ME likes this.
  6. Harttoo

    Harttoo Well-Known Member

    Blue Wide Glide and FXDL4ME like this.
  7. FXDL4ME

    FXDL4ME Member