Entangling in the extruder

A week ago I finished assembling my printer, after successfully printing some things the machine began to fail. First not come out plastic, then it began to tangle it to the extruder.
As you can see from the photos, printing starts fine, but after a while it starts to fail. I try solve that changing the material, increasing slightly the temperatures, but I could not fix this.
Anyone know any solution for this?, thanks and sorry for my bad English

Is that 1.75mm filament? If so, the gap between the drive wheel and the hot end entrance is much to big. Even the slightest resistance in the hot end would cause the filament to buckle like that.

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I had the same issue before. I found out that the heat from the block would creep to the aluminum block and buckle the filament (Specially 1.75mm)
Make sure your fan is going on full speed.
Print yourself a Greg extruder or something else ASAP

Yes, its a 1.75 mm filament. I will try to keep fan always on. Although I squeezed the filament with the drive wheel, the same thing keeps happening.
Is Greg extruder much better?, I have the parts but I bought a assembled extrusor thinking it would be better