Originally shared by paul wallich
(tl;dr: if you have a fan that cools your hot end or heat break, lubricate it. It may solve some problems.) It’s a good thing I splurged on the dual extruder for my printrbot way back when. Not that I use it very often, but entirely by accident it saved…
http://invisibleturtles.org/2016/10/28/lubricate-your-fans