Tarantula with jerky feed

Hi all, first post and quite a newbie on 3D printing so please have patients with an old man used to mills and lathes

Just bought me a Tevo Tarantula.. hit quite a few snags during build, bad manual etc but hey, at that price.
Anyway, seems to be running now BUT i have a problem getting it to feed enough.

Running with Repetier and Cura (Works a charm with my Fabrikator mini) but the Tarantula have this weird jerky action on the extruder stepper.
Feeds a bit then retracts with a harsh sound (very fast, almost like slapping a table).. video here Jerky feed

Parts i print do look OK but very flimsy and porous so i guess filament feed is too slow.

Any ideas? Is this retraction/clicking normal or is it a bug in firmware or slicer?

regards
/Joakim

Edit: Some pics too...
Fan guide.. see how transparent it is just below the bend:
Mounted on printer:

Edited 2 time(s). Last edit at 05/28/2016 04:56PM by Joakim.

Ok, problem is sort of solved.
Reason was the stepper lost steps.
I upped the current for the extruder stepper almost to max and now it seems to work.

Not sure why, perhaps a bad motor? It feels OK when i turn it by hand so no obvious friction.

I will order a new stepper and see if it gets better, a little worried running it so hard due to heat/over current.

/Joakim

Hi Joakim,
Can you explain how did you upped the current?
I am experiencing the same issue..

Thanks!

Hello,

I have this issue as well. I googled and searched for steps on increasing the current to no avail. No one has a clear answer.

How can I do this? Please help!

Thanks.