Material does not feed

Hi,
I recently ran into trouble with my material feed. Here is what I did so far:
The failure mode:

  • The feeder cogwheell turns evenly
  • There are only a few cm of material coming out of the nozze, then it stops (cogwheel still turning)
  • The material flows nicely when I push the filament gently through the feeder.
  • When unloading, I find feed marks on the filament.
  • I have used the same material for a few years now without changing the filament nor the material settings in Z-Suite
  • The M200 is 10 years old but scarcely used, maybe 100hrs.

Here is what I did so far:

  • remove nozzle, soak and clean in Acetone, until the hole was open.
  • put back nozzle, still very little feeding
  • still feed marks on the filament

What should I try next? Is this a common failure, should I replace the extruder or something else?
Thank You!

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