Slave Cylinder

Discussion in 'Technical' started by TommyGun1928, Apr 12, 2021.

  1. TommyGun1928

    TommyGun1928 Member

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    Hey guys just replaced the master cylinder in my Grabber and while bleeding the breaks the front right would not bleed. I'm still running drums at this time and plan on going to disc next year but for now I need to replace or rebuild the cylinder. The local parts stores don't carry the parts I need so I thought I would start here, any help you guys can give would be appreciated.
     
  2. tody

    tody Member

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    try rockauto.com, they should have everything you need.
     
  3. RMiller

    RMiller My name is Rick

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    Probably a plugged bleeder screw. Pull it out and clean out the passages with a small drill bit (spinning it by hand) if it is plugged.
     
  4. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    Or a collapsed brake hose/pinched hard line.
     
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  5. TommyGun1928

    TommyGun1928 Member

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    Thanks tody I'll try Rockauto. I removed the bleeder screw completely and no fluid would come out under pressure and the break line is not damaged or crushed as far as I could see. Now that the weather is warming up I can roll the Beast out of the garage and R/R the break assembly. Looking back over time I think this has been an issue and the mechanics never addressed it. The reason I say this is because I've replaced the top left ball joint more times than I care to mention indicating the left break was doing all the work. Already replaced the entire fuel system as well as overhauling the cooling and heating systems. Replaced the master cylinder and blead all the breaks with no issue until we got to the right front. I will recheck the line for damage, good point Mavman72 and I'll run a guitar string up the line to clear any clogs that might be there.
     
  6. Krazy Comet

    Krazy Comet Tom

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    If left brake were doing all the work, front would dive in that direction anytime the brakes were applied. Not uncommon for hose to collapse internally, restricting flow to wheel cylinder. When we're talking three or four hundred pounds of force, a guitar string is useless.
     
  7. TommyGun1928

    TommyGun1928 Member

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    The vehicle has been pulling left for years, I brought it to a few mechanics and the problem was never fixed. I guess I can be blamed but at the time I had no time to dig into the problem. Now that I'm retired I have the time to really get into the issues this vehicle has.
     
  8. Hippylong

    Hippylong Hippylong

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    I recommend using speed bleeders
    their like 5 bucks a pair.
    Basically , they are 1 way valves.
    Bleed a system by yourself.
    I also use them in hydraulic clutch slave cylinders.
    20210421_235324.jpg
     
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  9. Constable

    Constable You have the right to remain silent....or not!

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    Krazy is absolutely correct about the rubber lines collapsing internally. You have no way of knowing it has happened until it screws with the braking.
     
  10. Krazy Comet

    Krazy Comet Tom

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    If I remember correctly, '70 is unique to that year & hoses are all but unobtainium. The '71 uses different hoses and wheel cylinders, last time I checked were still available. What I don't know, do the '70 hard lines match hookup of '71 hoses? Ford is famous for changing nut size, of course there are adapters..
     
  11. TommyGun1928

    TommyGun1928 Member

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    Obviously these are inserted where the original bleeder valves are so do I need to use a vacuum pump? I'm using a hand vacuum pump now as well as the wife pumping the breaks and no fluid came out.
     
  12. TommyGun1928

    TommyGun1928 Member

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    How do I determine if this has happened? In the next week or so I will be able to pull the wheel and inspect the slave proper.
     
  13. Mavman72

    Mavman72 Gone backwards but lookin' forward

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    If you get no fluid out of the bleeder on the wheel cyl while pumping the brake pedal. (and your certain the wheel cyl isn't packed solid with rust/gunk) Disconnect the brake hose from the hard line and step on the brake pedal...If you get fluid from the line...Hose is bad.
     
  14. Constable

    Constable You have the right to remain silent....or not!

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    First, I'd make sure that the bleeder screws are backed out enough to allow flow. Seems a no brainer but can happen. If they are and you can't get flow with a Mityvac, I'd certainly suspect that the lines are collapsing under the vacuum pressure. You should be able to back the bleeders out completely to see if there might be crap obstructing the flow. Regardless, if you are bleeding the system anyway, the soft lines are cheap enough that replacing them shouldn't be an issue. I got mine from Rock but there may be some brick & mortar shops that can get them for you quicker if time is an issue.
     
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  15. mojo

    mojo "Everett"- Senior Citizen Supporting Member

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    If I had any idea hoses were an issue; I would just replace and move on! If they were unique to a specific year and hard to come by -- I would have them made at a hose vendor. Cost of not being able to stop -- much higher than cost of hoses!
     
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