My fan was making a lot of noise...

[filmbuff]

So I opened it up and saw this. The heatsink was completely clogged with dust. I cleaned it off with some Q-tips and WD-40 and the rattling noises stopped, and the Macbook runs a lot cooler now. The fan still gets loud if I'm playing youtube videos but it's a 100% improvement. Moral of the story: clean your fans at least once every 8 years!

 

[BrettApple]

I recently got an Early '08 Black MacBook off eBay and the fan was buzzing and rattling like crazy, especially noticable at higher RPM or when it was tilted around. I took it apart and lubricated it but it made no difference. I then ordered a fan off PowerBook Medic and replaced it. Smooth sailing after the replacement.

However, I've recently noticed the sound is starting to come back with this replacement fan. Not nearly as bad, but it's there. Luckily they're cheap (used) but that also means all of them are old and used. New ones are like $40, no thanks.