Ender 3: Cleaning Clogged Nozzle
Pre-heat to the Material printing Nozzle Temperature.
Cool down to an appropriate Cold Pull Nozzle Temperature, and do a Cold Pull.
Pre-heat to current Material Nozzle Temperature.
Placing Z Locks can help, but isn't necessary.
Remove the Hotend Fan Assembly.
The Nozzle is HOT. Please see the 3D Printing KB Disclaimer.
Clean up into the Nozzle using a Nozzle Cleaning Needle.
Remove the Heater Block Sock.
Remove the Nozzle. You can use a 6mm socket wrench.
Hold the Nozzle with Pliers and clean it using the Cleaning Needle and tweezers while it's still hot. You can also use a Brass Brush after it has cooled.
Remove the Bowden Tube Fitting from the Hotend.
Clean the tip of the Bowden Tube.
Remove the Bowden Tube from the Bowden Tube Fitting.
Push the Bowden Tube down through the Hotend.
Clean the tip of the Bowden Tube.
Pull the Bowden Tube up out of the Hotend.
Cool down the Nozzle Temperature.
Clean the tip of the Bowden Tube.
Install the Bowden Tube Fitting.
Inspect the Nozzle to make sure it is clear. If it's not you will need to clear it, or install a New Nozzle. Note: You might be able to use an Air Compressor to clear a Nozzle.
Install the Nozzle, leave the Nozzle one full rotation loose.
Install the Bowden Tube.
Install the Bowden Tube Fitting Clip.
Tighten the Nozzle fully.
Install the Heater Block Sock.
Install the Hotend Fan Assembly. While tightening the screws apply thumb pressure pushing the Assembly up as high as it can go.
Remove any Z Locks if they were used.
Nozzle replacement is complete.
Also see Replace Nozzle.