If you have a Ford 740 series loader with the original double valve with float, above each spool control is an assembly with check valves and relief ports. There are forward and reverse relief valves in each spool body. These are not the simple single relief valve type that are found on most ag tractors. I would not attempt repair unless you are experienced and have the repair manual and parts diagrams in front of you (and take lots of pictures as you progress, you will need them for reference when reassembling).
If you have the valve for the Drott four-in-one bucket, it is best to just take it in to a hydraulic shop and have it rebuilt professionally.
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