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Relief valve? Rebuild?

Troy4500Industrial

Active Member
Joined
Aug 2, 2018
Messages
39
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
 

Troy4500Industrial

Active Member
Joined
Aug 2, 2018
Messages
39
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
 

Larryv

Member
Joined
Feb 22, 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 .
 

Larryv

Member
Joined
Feb 22, 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 .
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.
 
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