clean the dust before
45 minutos - 1 hora
My left fan was noisy, I thought it was dying. So I bought a new one. I followed the very clear guide.
The repair went as expected, except that I noticed that my fan was actually full of dust: a dust bunny was hitting the fan blades, hence the noise. I still replaced the fan, to be sure, but the old one seems perfect, after the cleaning. Of course I cleaned the right fan also, which was full of dust, too.
Mind the plastic clips, as advised during step 8.
Clean the dust before buying a new fan.