Hello, I am trying to use a David brown 885 with a loader on. Oil is slightly low but is still visible in the sight glass. But we have no hydraulics, loader won’t move nor will the 3 point linkage. Have tried the three way valve in all positions with the position leaver all the way up and nothing it doesn’t even try. The three way valve leaver is connected and seems to be working. Anyone know where to start? Also asking what this turning knob does and what position you need it in to use the loader it seems to turn freely as if not connected to anything?