Fixing a problem with filament feeding

I’ve been annoyed for the last week as my Ender 3 was not printing anything. It’d worked so well for a while, then all of a sudden no filament would come out.. or just a little bit would dribble out. I cleaned the nozzle two dozen times and cleared any clogged bits, cut off the filament end and jammed it hard into the hot end, but to no avail.

It was time to do some research as to why my filament would not feed. I watched some YouTube videos and even though my printer was a different model I saw a potential fix and decided to investigate. It turned out to be the same as my problem!

Ender 3 extruder cog

The extruder cog which feeds the filament through to the bowden tube had loose allen bolts and it had slipped down and was not touching the filament. This meant it could not push the filament through the bowden tube! The brass cog you can see above is the culprit!

Line up the cog with the feeder disc

Firstly, line up the cog with the feeder disc and tighten all screws. I had pulled the whole assembly apart, but you don’t need to as you can get to the tiny, black allen bolts easily enough by turning the brass cog by hand.

The filament now feeds through the cog

Also, make sure the peg on the spring is open fully. Mine is stiff and doesn’t open enough to help grip the filament. I may need a new one in the future.

Video of cog feeding filament

As you can see in this video, the cog now successfully feeds the filament through and the filament comes through the nozzle and onto the heated bed.

I have already ordered a new bowden tube and connectors which I will of course add later but they aren’t as urgent as I had thought. I figured this would resolve my issue but it wasn’t the bowden tube at all.

  1. Thanks! Just got my ender 3 pro a few days ago and my first overnight print failed. This was the exact problem!

  2. Hi Jason,
    I have same issue. The printer printed 1st model fine and then it stopped. What did you use to tighten black allen bolts? That bold is very tiny.

  3. apoorva singal

    You helped me fix my problem. This was exactly the problem

    I loosened the nuts on the brass gear, lifted it so that its teeth are aligned and tightened the nuts and Voila…it worked!!

    Thanks so much

Leave a Comment

NOTE - You can use these HTML tags and attributes:
<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <s> <strike> <strong>

This site uses Akismet to reduce spam. Learn how your comment data is processed.