Extruder not pushing filament all the way through PTFE tube
Any filament I load is pushed through the top of the tube, but after 5-6 seconds, the filament stops moving although the extruder motor is still moving. Pushing the filament through manually with my hands works.
I have replaced the PTFE tube (carefully following steps in https://help.prusa3d.com/en/guide/how-to-replace-ptfe-tube-on-the-mk3s-mk2-5s-mmu2s_21664), replaced the nozzle and recalibrated the printer, all with no luck.
I also tried tightening/loosing the spring-loaded side screw, with no luck. The gear seems to be correctly aligned.
Check that the bondtech wheel is correctly mounted on the motor shaft. The small stop screw must sit against the flat end of the axle, otherwise it will only slide on the shaft.
With a correct spring tension, you should in principle be able to lift the printer in the filament without it slipping out.