After a while my eleaf GS air/tank/air2 coils tend to get hard to draw through. I suspect they are gummed up. I have seen some videos on youtube to disassemble them but I don't think I would get them back together. Is there a way to clean them to keep using them? Dip them in ????? and then _____________ to get all the ????? back out? Anyone have experience with this?