Correct Torque For Master Cylinder 'y' Fitting

Discussion in 'Flat Fender Tech' started by SoCalNickG, Aug 9, 2017.

  1. Aug 9, 2017
    SoCalNickG

    SoCalNickG New Member

    Los Angeles, CA.
    Joined:
    Mar 17, 2017
    Messages:
    14
    In the process of replacing the master cylinder on my MB and I couldn't help but notice that the copper crush washers on either side of the 'Y' fitting were really crushed. The machined grooves in the Brass 'Y' fitting were mated to the copper washers to the point that the imprints are pressed into the copper. When these were assembled it was torqued so far that the brake light switch side copper washer was mashed into the gap of the banjo bolt. The machine marks on the end of the master cylinder are even visible in the master cylinder side washer.[​IMG]
    I had the master cylinder off the jeep and needed a vise to break the banjo bolt loose. This thing was on tight. As far as I know this could be the original master cylinder. I've owned the MB since 1984 and I've never had to change the master cylinder until now. While I wait for the new copper washers I thought I would pick the communal brain trust and ask "What is the banjo bolt supposed to be tightened to?".

    .[​IMG]
    [​IMG]
    The fitting was not leaking before it was removed. I want to put it back together with out leaks but how much to tighten the banjo bolt. I know, I know "more pictures", here's two of the MB in my warehouse. Thanks for any help.
    [​IMG] [​IMG]
     
  2. Aug 9, 2017
    Howard Eisenhauer

    Howard Eisenhauer Super Moderator Staff Member Sponsor

    Tantallon, Nova...
    Joined:
    Nov 22, 2003
    Messages:
    4,537
    The FSM doesn't seem to discuss this :(.

    It doesn't take much to crush those copper rings, they're pretty soft so you don't need to crank the banjo bolt very hard to get a good seal.

    Don't re-use the old ones- you need to use new ones.

    H.
     
  3. Aug 9, 2017
    SoCalNickG

    SoCalNickG New Member

    Los Angeles, CA.
    Joined:
    Mar 17, 2017
    Messages:
    14
    I've ordered new washers already from Walcks.
     
  4. Aug 10, 2017
    Glenn

    Glenn Kinda grumpy old man Staff Member Sponsor

    Apopka, Fl
    Joined:
    Sep 21, 2002
    Messages:
    7,431
    I usually start with snug and then just a tad more. Check for leaks after that, you definitely shouldn't have to bear down on something that is designed to crush and seal.
     

Share This Page

New Posts