Double check your hyd. fluid level. Sounds like you have air in the lines.
Then raise the loader and hold the joystick in curl up function for several seconds then do the same for curl down. After several cycles you should be able to get the air out. They will self bleed by cycling.
If for some reason you removed the loader from the tractor the problem may be in the hyd. couplers. You may need to unhook them and reconnect them.