Yes that the upper picture seems like leaking? I see plastic coming from the upper part of the block down to the bottom part also covering the nozzle. As it comes from there its probably leaking through the upper thread. You may need to fix the leak if there is one. Could use some teflon plumbing tape thats made to seal threads on metal plumbing pipes. Also i read some posts back, i think you should try printing with lower speeds than 150, try with 70 and see if there is anything different just in case thats the cause. You can also extrude in air and see if the filament is uniform and extrudes nicely.
Also should find the reason why is hard to push, if the nozzle can be dismantled and left with the block alone, then could try pushing the plastic like that without nozzle but still heated up, and wait for the filament to dilate and see if the filament dilatation is to blame, or else if the nozzle is at fault. If the filament dilatation is to blame, you could check the exact diameter of your hole and say if it is 3.0mm could increase it to 3.2 with a drill, this is an idea. But by now if the inner diameter would of been 3.0 or less and heated up to 230c probably by now the cooled filament would of been already stuck, so probably its not that. Perhaps the nozzle was blocked, which would build pressure and get it leaking if thats the case. If the nozzle was not blocked by something, then perhaps its inner diameter is too small, make sure it is 0.4mm or bigger, and use lower speed settings in slicer program - halve all speeds related to extrusion.
The plastic quality probably does not have any impact, not like that at least. Must be something with extruder hardware issue, or slicing parameters being bit high, but probably both. Dunno what else, as thats all that is involved.
Also should find the reason why is hard to push, if the nozzle can be dismantled and left with the block alone, then could try pushing the plastic like that without nozzle but still heated up, and wait for the filament to dilate and see if the filament dilatation is to blame, or else if the nozzle is at fault. If the filament dilatation is to blame, you could check the exact diameter of your hole and say if it is 3.0mm could increase it to 3.2 with a drill, this is an idea. But by now if the inner diameter would of been 3.0 or less and heated up to 230c probably by now the cooled filament would of been already stuck, so probably its not that. Perhaps the nozzle was blocked, which would build pressure and get it leaking if thats the case. If the nozzle was not blocked by something, then perhaps its inner diameter is too small, make sure it is 0.4mm or bigger, and use lower speed settings in slicer program - halve all speeds related to extrusion.
The plastic quality probably does not have any impact, not like that at least. Must be something with extruder hardware issue, or slicing parameters being bit high, but probably both. Dunno what else, as thats all that is involved.