SV08: no filament comes out, the extruder spins without feeding or it clogs mid-print
Guide based on the manufacturer's official documentation; usi3d has not yet verified it on a machine.
Technology: FDM · Brand: Sovol · Symptoms: Clogged nozzle or hotend, No filament comes out, The extruder clicks or skips · Updated on 9 October 2026
Symptom
On the SV08 the extruder turns but no filament comes out, loading works but it clogs during the print, the nozzle does not extrude although filament comes out once the nozzle is removed, or parts come out spongy and weak.
Likely causes, from most to least likely
- The 2515 side fan on the heat sink does not spin: the throat heats up, the filament softens too early and swells (if the tip is thicker than 1.75 mm when pulled out, it is this or too high a temperature).
- The extruder gear is loose (it has a small fixing screw), misaligned because the lever's metal shaft has moved, dirty or worn.
- The extruder spring pressure (hand nut) is too loose or too tight.
- With the enclosure kit fitted, the chamber goes above 35 °C when printing PLA, PETG or TPU.
- Too low a temperature for the speed, silk filament printed too fast, or a nozzle of another material (the stock one is hardened steel) without adjusting speed or temperature.
- A clogged, enlarged or burred nozzle, or brittle filament or a diameter other than 1.75 mm.
Checks to tell which one it is
- Heat the nozzle to 60 °C and check that the 2515 heat sink fan spins; if Mainsail shows Error 8 with «Fan», it is the fan.
- Pull the filament out and look at the tip: tooth marks mean the gear chews without feeding; a swollen tip means heat in the throat.
- With the printer off, remove the toolhead fan cover, loosen the extruder clamp and look at the gear: its small screw must be tight and the lever shaft in place.
- Locate the clog: if filament comes out once the nozzle is removed, it is in the nozzle; otherwise in the throat or the extruder.
Before you start
Before taking anything apart, cleaning or adjusting it, switch the printer off and unplug it, unless a step says otherwise, and do not touch the nozzle, the heater block or the bed until they have cooled down. If in any doubt about electricity, heat or moving parts, stop and ask a professional.
Step-by-step fix
Check the heat sink fan
If the 2515 fan does not spin when heating, follow Sovol's solution for Error 8 with «Fan» (Fan1 port cable, adapter board or fan).
Check: The fan spins and the filament no longer swells in the throat.
If that does not fix it: Check the extruder (next step).
Adjust the extruder gear and spring
With the printer off, tighten the gear's small screw. If the lever's metal shaft has moved, push it back into place and fix it. Clean debris off with tweezers and a brush. Adjust the spring's hand nut (clockwise tightens) so the pressure is neither loose nor excessive.
Check: The filament feeds without deep tooth marks.
If that does not fix it: If the gear is worn, ask Sovol for a replacement.
Clear the nozzle, throat or extruder
Nozzle: hold it with a tool, heat it separately, clear it with the needle and push new filament through; if it will not clear, replace it. Extruder: take it apart and pull the filament out with tweezers, softening it with a hair dryer or hot air gun if swollen. Throat: warm it with a hair dryer until the filament softens, remove it and push new filament through. Careful: hot parts burn.
Check: New filament comes out of the nozzle continuously.
If that does not fix it: Check temperature and speed (next step).
Adjust temperature, speed and enclosure
Slice with the filament's temperature. With silk filament, Sovol recommends reducing speed by 30% (about 120 mm/s at 0.2 mm layers). If you replaced the stock nozzle with one of another material, lower the speed or raise the temperature. With the enclosure kit, when printing PLA, PETG or TPU open the glass panel or fit the top kit so the chamber stays below 35 °C.
Check: The print finishes without clogs and parts come out solid.
If that does not fix it: Send Sovol the result of each check.
Prevention
- Check every now and then that the heat sink fan spins when heating.
- With the enclosure fitted, do not print PLA, PETG or TPU with the chamber above 35 °C.
- Use dry 1.75 mm filament and a temperature suited to the speed.
Still not fixed?
Tell usi3d's AI about your case: choose your printer, describe what you see and add photos if you like. It proposes checks step by step, with their sources.
Printers it applies to
Sovol SV08.
Official sources
This guide summarises the official documentation linked here:
This guide is general information: usi3d has summarised it from the official documentation linked here, and it may not match your model, its version or its firmware. If in doubt, follow the manual and the support of your printer's manufacturer. You decide what you do with your machine, and working on it may affect its warranty.