Tractor Repair: NAA Hydraulics, naa, lift

Question
Have a Golden Jubilee NAA with no hydraulic lift pressure.  Have had the lift cylinder rebuilt and have also had the hydraulic pump rebuild (piston type) and can not get any oil to flow through the pump.  I have taken the plug out of the pump and hooked it to a hose and ran it back to the lift housing.  I have pressurized the housing and am still unable to get oil flowing.  The hydraulic lines are open with no restrictions.  I took the pressure relief valve out and disassembled it but all that is there is a spring and a cap to hold the spring in place.  Should there be something else in the relief valve?  I'm at my wits end and would appreciate any help/information, etc. so I can get my tractor power lift operational again.

Thanks,

Roger

Answer
there should be a small spool on the end of the spring and some method for adjusting the pressure either shims or adjusting screw .the small spool could be what you are calling the cap as far as i know you should be able to take a cover off the right side of the gear box where the dipstick goes in start the tractor and put the lift lever in the up position and look in and see if you can see oil spraying out of any where (relief valve,control spool,lift cylinder,) this should give you an idea of what is happening.Do this and let me know what you find and i will try help further