I have a 5093e and the hydraulic fluid is only showing in the bottom sight glass and none in the top, so I poured some more in and it showed about half way up on the top glass,so I started it and let it run for a few min and worked the loader up and down and now it shows only in the bottom glass again. Do I keep pouring till it gets in the top glass? Also do I do it with the tractor running or what? Thanks for the help.