I've recently built the Prusa i3 from RepRapGuru and it was working fine (with minor hiccups), but decided to change the hotend. The new hotend was not what I anticipated so the original hotend is back on. My problem was with the reassembly. It seemed pretty straightforward, but not the extruder will take the filament extrude a little and then the filament reverses direction. The stepper is continuing to move correctly, but it seems that the extruder is letting go. I suppose I need a diagram to reassemble the hotend, etc. Any help would be appreciated.