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Relief valve? Rebuild?

Discussion in 'Tractor/Loader/Backhoes' started by Troy4500Industrial, Feb 23, 2021.

  1. Troy4500Industrial

    Troy4500Industrial Active Member

    Joined:
    Aug 3, 2018
    Messages:
    31
    Location:
    Ishpeming, Michigan
    Hey guys,

    My 74’ Case 580B has been leaking from this for a while ... I unthreaded it and replaced the o rings last year, but it’s leaking internally from under cap/c clip ... is this a relief valve and how difficult is it to repair? I can’t seem to find any schematics on it
    upload_2021-2-23_14-14-2.jpeg
     
  2. Tinkerer

    Tinkerer Senior Member

    Joined:
    May 21, 2009
    Messages:
    6,015
    Location:
    On A Riverbank in IL. USA
    I think this is it.
    val.jpg lis.jpg
     
  3. Troy4500Industrial

    Troy4500Industrial Active Member

    Joined:
    Aug 3, 2018
    Messages:
    31
    Location:
    Ishpeming, Michigan
    Thanks! Mine may or may not be a little different with mine having a c clip holding what seems to be a cap down but I think this will help me out a ton with taking it apart ... I'll post pics of what I come across, thanks again! @Tinkerer
     
  4. Tinkerer

    Tinkerer Senior Member

    Joined:
    May 21, 2009
    Messages:
    6,015
    Location:
    On A Riverbank in IL. USA
    If you want the parts book PM me your email address.
     
  5. Larryv

    Larryv Member

    Joined:
    Feb 23, 2021
    Messages:
    18
    Location:
    So. Illinois
    If you release pressure on all cyls. Remove the relief and it easier to get that small plug out that's held in by inside snap ring. They will tend to hold moisture and rust. That valve is a sort of relief as it's a circuit relief. Protects cylinders from a manual overload. Its setting is like 500 psi over main relief. They are all the same except for the pressure setting. The relief for the boom down circuit is set way lower than Main relief to protect The boom cylinders .
     
  6. Larryv

    Larryv Member

    Joined:
    Feb 23, 2021
    Messages:
    18
    Location:
    So. Illinois
    If you unscrew that Allen head adjusting screw, count the number of turns you make to be sure to return to where it was
    That's the pressure setting screw.