<p>I have a weird problem over here, I'm restoring an FLSUN Kossel Mini (with a RAMPS 1.4 board) and it printed fine for the last two days.</p>
<p>Now when I initiate a print job, the extruder motor doesn't push filament into the nozzle ( it retracts filament like it's supposed to, it just doesn't push.) and this only happens during a print job.</p>
<ul>
<li>I cleaned the nozzle</li>
<li>Increased/decreased printing temp.</li>
<li>Swapped motor drivers.</li>
<li>Adjusted Z offset.</li>
<li>Reset the motherboard.</li>
<li>Changed acc and jerk values.</li>
</ul>
<p>None of these did the trick for me, and when I manually control the extruder motor (from the LCD or Repetier) it pushes the filament without any problems.</p>

CC BY-SA 4.0
2024-01-13T23:35:46.433Z
Is it turning at all? Are there signs of filament grind? Does it fail from the start or at some point during the print?  Is coldside hot?..
Mołot
CC BY-SA 4.0
2024-01-14T08:47:01.110Z
Yes it turns fine, and the whole extruder assymbly is clean from any grind or debris.
Ghazi Faisal
CC BY-SA 4.0
2024-01-14T08:49:44.297Z
The extruder doesn't pull filament from the start of the job, but weirdly enough it retracts the fillament when z hopping.
Ghazi Faisal
CC BY-SA 4.0
2024-01-14T17:13:35.337Z
Are you sure you are sending good gcode? And have you tried to remove hotend altogether, to make sure it has no part in the issue?
Mołot
CC BY-SA 4.0
2024-01-14T17:24:21.887Z
Yes I did, first I used the didcated extruder buttons on repetier then tried with G1 commands, and both seemed to move the stepper motor fine.
Ghazi Faisal
CC BY-SA 4.0
2024-01-14T17:25:50.670Z
Another thing I noticed was fillament wasn't extruded on the first 3 layers, when the print job reaches layer 4 the extruder motor returns to pumb fillament.
Ghazi Faisal
CC BY-SA 4.0
2024-01-14T17:26:54.587Z
I eleminated the clogging/jaming possibility by romoving the filament wire and starting a print job.
Ghazi Faisal
CC BY-SA 4.0
2024-01-14T17:27:24.333Z
This is when I found about the 3 layers problem.
Ghazi Faisal
CC BY-SA 4.0
2024-01-14T17:28:43.477Z
Can the extruder stepper be damaged in this case?
Ghazi Faisal
CC BY-SA 4.0
2024-01-14T19:23:28.017Z
Extruder motor works or it does not. It's not layer dependent. It seems your works. Check hour hcode
Mołot
<marlin><troubleshooting><extruder><ramps-1.4><underextrusion>
Extruder motor doesn't pull filament during job only
Ghazi Faisal
# Extruder motor doesn't pull filament during job only

(Asked by: username_0 on 2024-01-13)

I have a weird problem over here, I'm restoring an FLSUN Kossel Mini (with a RAMPS 1.4 board) and it printed fine for the last two days.

Now when I initiate a print job, the extruder motor doesn't push filament into the nozzle ( it retracts filament like it's supposed to, it just doesn't push.) and this only happens during a print job.

* I cleaned the nozzle
* Increased/decreased printing temp.
* Swapped motor drivers.
* Adjusted Z offset.
* Reset the motherboard.
* Changed acc and jerk values.

None of these did the trick for me, and when I manually control the extruder motor (from the LCD or Repetier) it pushes the filament without any problems.

**Tags:** marlin, troubleshooting, extruder, ramps-1.4, underextrusion
> **Comments:**
> **username_1**: Is it turning at all? Are there signs of filament grind? Does it fail from the start or at some point during the print?  Is coldside hot?..  
> **username_0**: Yes it turns fine, and the whole extruder assymbly is clean from any grind or debris.  
> **username_0**: The extruder doesn't pull filament from the start of the job, but weirdly enough it retracts the fillament when z hopping.  
> **username_1**: Are you sure you are sending good gcode? And have you tried to remove hotend altogether, to make sure it has no part in the issue?  
> **username_0**: Yes I did, first I used the didcated extruder buttons on repetier then tried with G1 commands, and both seemed to move the stepper motor fine.  
> **username_0**: Another thing I noticed was fillament wasn't extruded on the first 3 layers, when the print job reaches layer 4 the extruder motor returns to pumb fillament.  
> **username_0**: I eleminated the clogging/jaming possibility by romoving the filament wire and starting a print job.  
> **username_0**: This is when I found about the 3 layers problem.  
> **username_0**: Can the extruder stepper be damaged in this case?  
> **username_1**: Extruder motor works or it does not. It's not layer dependent. It seems your works. Check hour hcode  

---

## 0 answers

