After replacing memory please try to reset smc and pram. It worked for me. It is always wise to do this after changing any hardware inside your mac. Also run memory test with built-in apple hardware test suite (hold D while booting) or/and memtest. Maybe you just got a bad ram. Happened to me twice!!

You can find replacement fan on ebay. The part is labeled as BSB0712HC-HM01 and it costs about 24 USD. Before replacing try oiling the shaft of the fan (pull it up straight! - oil the shaft, not the mechanism!) - it worked for me.

Hello Mark, I broke mine too - the connector. The three wire connection cable goes to the green/yellow status led. If you can’t live without it like I could not :) than you can use some superglue (gel!) and try to reassemble the connector back with much patience and steady hand. Wait at least 2 hours to dry out completely!! I used Loctite super attach gel. It worked for me. Two wires were lose and one was still on the connector. Next time I open my unit I will not touch this connector but instead rather remove the LED from housing and let it stay connected to the board.

I opened my unit to expect it before I buy the new fan because I found fan failure in debug log of my airport utility instead of overheat which was presented right after login into airport utility. The fan costs about 23$ on ebay - not cheap at all!! Turns out the fan is OK but it just needed a bit of oil because it could barely spin (with my hand! on it's own id did not turn at all). I opened the fan casing - be careful no to break the plastic clips and pulled the fan straight up from the mechanism. What can go wrong, if its broken its broken, right? :) … I put a very small amount of oil on the shaft itself (not in the mechanism!!!) and pushed it back to into the mechanism. Then I tried to turn the fan a bit both ways with my hand and with each turn it had less resistance. When I plugged the disassembled unit into power (I really really really do not recommend that!!!) the fan started to turn on its own. The unit is now fully assembled and works for the past 2 days without overheat warning. Hope this helps!