Why does my master cylinder leak at the top?

Discussion in 'Technical' started by facelessnumber, Oct 7, 2009.

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  1. facelessnumber

    facelessnumber Drew Pittman

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    I have replaced the gasket, then the cover, and the bar that goes on top of it, yet it still leaks all around the the top of the reservoir and it always has. It's clean, it's not damaged, it works fine... What am I doing wrong? Overfilling it, maybe? It doesn't really seem to matter where the level is. This is a disc/drum power brake cylinder.
     
    facelessnumber, Oct 7, 2009
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  2. rthomas771

    rthomas771 Member

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    Mind did the same. I replaced the spring hold down with a Ford part from the junkyard. The aftermarket retainer clip fit to loose. I can not remove the top now without using a screwdriver.
     
    rthomas771, Oct 7, 2009
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  3. facelessnumber

    facelessnumber Drew Pittman

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    So it's that simple then? The stupid top just isn't on tight enough?
     
    facelessnumber, Oct 7, 2009
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  4. mercgt73

    mercgt73 Member Supporting Member

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    You could also try and run a flat file across the top of the master cylinder, maybe there is an imperfection you are not seeing? :huh:
     
    mercgt73, Oct 7, 2009
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  5. facelessnumber

    facelessnumber Drew Pittman

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    I considered that, but it's leaking uniformly all around it. I will check it with a straight edge though.
     
    facelessnumber, Oct 7, 2009
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  6. Columbus Comet

    Columbus Comet Member

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    Mine did the same thing with the chrome cover, put the factory one back on and fixed it. I hated it leaking down on the nice and clean steering gear box.
     
    Columbus Comet, Oct 7, 2009
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  7. facelessnumber

    facelessnumber Drew Pittman

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    I replaced a factory one with a chrome one trying to fix the leak. Factory sucked just has hard as aftermarket. But it's probably the spring/bar thing.
     
    facelessnumber, Oct 7, 2009
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  8. Jsarnold

    Jsarnold Senior Member

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    I'd be very concerned about getting metal filings in the reservoir and ruining all the cylinders.:yikes:
     
    Last edited: Aug 13, 2011
    Jsarnold, Oct 7, 2009
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  9. mercgt73

    mercgt73 Member Supporting Member

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    Ofcourse, I figured he would put rags in the reservoirs before and clean them before adding fluid. :yup:
     
    mercgt73, Oct 7, 2009
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  10. facelessnumber

    facelessnumber Drew Pittman

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    Nah, the grit will give me more stopping power!
     
    facelessnumber, Oct 7, 2009
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  11. blugene

    blugene Senior member

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    If it looks like the surface is uneven or pourous, you could remove it and file/grind it down on a flat surface upside down. I have a receipt for mine so it would go back to NAPA. :drive:
     
    blugene, Oct 7, 2009
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  12. facelessnumber

    facelessnumber Drew Pittman

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    If I end up needing another one, I will probably stay true to my usual habits and get something that doesn't belong in a Maverick. I hear certain Dodge trucks have one that fits and works will with four discs... Either that or I'll find a Ford one that bolts on and has a plastic reservoir, if such a beast exists.
     
    facelessnumber, Oct 7, 2009
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  13. rthomas771

    rthomas771 Member

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    '90 Ranger...use your pushrod.

    [​IMG]
     
    rthomas771, Oct 8, 2009
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  14. Bob Wiken

    Bob Wiken Chronologically Gifted

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    Mine does the same too. I guess i'll try to sort throughthe parts i have and mix Mix and match
     
    Bob Wiken, Oct 8, 2009
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  15. facelessnumber

    facelessnumber Drew Pittman

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    Interesting. I have power brakes, does this matter?

    What kind of valve are you using with this, if any, and do you have disc/drum or disc/disc?


    Edit: Also, I see there are two types listed for 1990: Before 3/90 and after 3/90. The later one appears to be angled upward. Which are you using?
     
    Last edited: Oct 8, 2009
    facelessnumber, Oct 8, 2009
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