bobcat 322 pilot control

I have a bobcat 322 thats been setting awhile it done this the last time I cranked it about 2 years ago.but I got it working. the pilot pressure control valve is stuck I took the valve apart cleaned it but it still does not work the magnet has some pull when it's energized my ?? is there is two cartridges on the same block and round steel ball about the size of a baseball is that a nitrogen accumulator if so can I check and recharge it .I have a charge kit for hammers . what pressure. could this be bad and causing it not to release pilot control pressure