Close



Results 1 to 11 of 11
  1. #1
    FEP Senior Member liv2roc's Avatar
    Join Date
    Jul 2009
    Location
    Cherryville n.c.
    Posts
    774

    Default Need help with brakes

    I have a 84 gt350 lost all brake fluid from master cylinder few days ago front and rear. I changed the master cylinder and went ahead and changed the booster because it is 35 years old whlie I had cylinder off. now I bleed the cylinder and all brakes and the peddle going down about a 1/4 way easy then gets hard and brake will put you though the windshield. theres no stopping easy. its not locking up just stops hard. I can get on brakes hard and it will not lock up any wheels but sometimes the rears will drag a few feet. do a have a bad new master cylinder?

  2. #2

    Default

    Where did all the fluid go?... are all the brake lines and wheel cylinders and calipers okay?... jumpy brakes or dragging rear drum/s sounds like fluid contamination on the brake lining material...
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  3. #3

    Default

    Leaking wheel cylinders. Brake fluid or 90wt? Did you bench bleed the m.c.?

  4. #4
    FEP Senior Member liv2roc's Avatar
    Join Date
    Jul 2009
    Location
    Cherryville n.c.
    Posts
    774

    Default

    I bench bleed the m/c. it lost fluid in both front and rear see no leaks anywhere but under m/c it ate my fuel lines. dont know where fluid came from but fuel line were soaked. I think it leaked out between the m/c and booster maybe a rear seal in m/c. how esle will it loose both front and rear.

  5. #5

    Default

    Out the back of the m.c. probably a good call replacing the booster. The cir-clip was broken on mine. All leaked out the back. Don't forget to wash down the area real well to minimize the fluid damage. As far as contaminate fluid. Did the lid gasket look ok or was it soft and misshapen? If it was you need to replace EVERYTHING that has rubber in it, ie. All calipers, wheel cylinders prop valve. I have flagged vehicles like that in the past.

  6. #6

    Default

    Okay. It can lose front and rear by first losing from one, then both... but usually out of either front/rear lines/components. There are a number of seals internal to the master cylinder where not all of front and rear will all exit out the back. Was the booster full?
    Mike
    1986 Mustang convertible ---> BUILD THREAD
    Past Fox-chassis "four eyes":
    1983 Mercury Cougar LS
    1986 Ford Thunderbird ELAN
    1980 Capri RS Turbo

    Work in progress website ---> http://carb-rebuilds-plus.boards.net/

  7. #7
    FEP Senior Member liv2roc's Avatar
    Join Date
    Jul 2009
    Location
    Cherryville n.c.
    Posts
    774

    Default

    booster was dry. why would I need to change everything with rubber in it?

  8. #8
    FEP Senior Member liv2roc's Avatar
    Join Date
    Jul 2009
    Location
    Cherryville n.c.
    Posts
    774

    Default

    booster was dry. why would I need to change everything with rubber in it? no fluid found anywhere but below m/c. where did it go, how did it get out without getting in booster?

  9. #9
    FEP Super Member erratic50's Avatar
    Join Date
    Dec 2016
    Location
    Nebraska
    Posts
    4,575

    Default

    Were the bolts master cyl to booster tight?

    What does visual inspection of the bottom side of the old stuff and the flange where the master cyl seats suggest?

    is it possible the shape of the booster let the brake fluid run out rather than in?
    Last edited by erratic50; 10-31-2017 at 09:32 PM.

  10. #10

    Default

    You only need to replace rubber parts if there is contamination. The tell tale is a soft spongy m.c. lid gasket that is growing or deformed. If you aren't sure have a pro check it. It can be a dangerous situation. It is not very common but it does happen. someone could have used dot 5 fluid or any number of other non dot 3 fluids to top off the m.c.

  11. #11
    FEP Senior Member liv2roc's Avatar
    Join Date
    Jul 2009
    Location
    Cherryville n.c.
    Posts
    774

    Default

    well I got her fixed. put the old booster back on and all is great. new booster was bad or rod was not set right.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •