Case 530 ck Pressure relief Valve questions

[TMZ]

Hi All!
Im trying to get to the bottom of my boom cylinder drift on my 32 backhoe.
I know that it could be the pressure relief valve o rings or not working properly.

there is one boom cylinder relief valve at the top and one at the bottom of the valve assembly.
low pressure and high pressure respectively I believe.

I pulled the top one out today but could only get the top of the valve , the poppet and the spring., the seat did not come out.
I did not know how to pull it out and wasnt any way for me to get anything in there and try and pry it out. so I just re assebled and no difference.
i tried adjusting the pressure setting screw in a few turns but that didnt do anything either.

does anyone know if it is it usually the top low pressure valve that is the issue in relation to drift, or the lower High pressure relief valve that causes the issue?
to remove the lower one I will need to remove the whole backhoe valve unit ....

I have repacked the boom cylinder and repacked all the spool valves which stopped the leaks but not the drift.
only the boom cylinder is drifting....

any suggestions or shared knowledge would be appreciated.
many thanks in advance
TMZ

 

[mEl]

TMZ , you should be able to blow that seat out by removing the spring and upper plunger and screwing the valve back in a few threads then energize that system by moving the lever with the engine running maybe half throttle. Hydraulic pressure will unseat it and it can be removed with a small magnet A bigger issue is that you have turned the adjustment so that will positively reset to specs in a fixture that Case Ce shop should have. or use a hand operated pressure pump to pump back against the valve to reset it. if you do not have it set to proper pressure, hoses and cylinder rods and barrels can be blown or broken and if the boom down pressure is to high a dangerous operation situation can be created. If I am correct the operating pressure may be stamped into the cartridge.

 

[TMZ]

Ok. Thanks so much for the info.
I turned the screw in 2 turns
And then back out 2 turns so it is physically in the same place. not sure if that is good enough or If I need it tested anyways.
Also it is the top side relief valve I messed with which I believe is the low pressure relief for boom down pressure
From the parts manual I viewed the bottom of the control valve has the high pressure relief valve which I have not touched yet. Im
hoping that I just need to replace the o-rings to stop the drift.
also The main pressure relief valve is not working properly. engine wants to stall when cylinders are etended to the ends,
i may try and back it off 1/2 turn at a time to see if I can get it to work.


Many thanks for the input.

 

[mEl]

Do ur self a favor and get a 0-6000 liquid filled gage, they are cheap, should be able to find one at tractor supply or similar store, the rod end of the cylinder holds it up so follow that hose back and see which port it goes into on the valve, that is the secondary for that end of the cylinder

 

[TMZ]

Copy that.
Does the gauge get T’d in series with that rod end line at the control valve for pressure reading?