1977 MF 30 industrial tractor hydrolic problems..

[toxicjeeper]

Hey all.. i have a 77 mf industrial tractor/backhoe...i was using the backhoe yesterday no problem after fixing a couple hoses that bust ( tractor hasnt been used in 2 years). Anyway i went to use it today and the backhoe part isnt getting any hydrolic pressure. The loader works but it seems like the pressure is in a reilf mode because the pump got very warm quite fast and squealed a little but that went away when i started moving the loader up and down. I think the problem may be in the spool vavle but could use any help, tips and advice i can get.. Will try to post a couple pictures later. Thanks

 

[toxicjeeper]

 

[toxicjeeper]

Here is a picture of the spool.. I thought i read somewhere there was a screen or some way of cleaning it out but am not sure which bolt to undo..