Little spare part - great effect
The right fan of my trusty MBP 17" late 2007 did all at once an incredible noise that it was impossible to work. All activities especially applications using the graphic card raised the temperature and thus the noise. For diagnosis I went to my local reseller who told me that this MPB is a vintage model and there are no spare parts from Apple available any more. This was the moment I decided to do the repair myself.
The order was placed at iFixit and the delivery arrived at the time scheduled. Additionally to the exchange of the fan I decided to replace the thermal paste between heat pipe and logic board as well. The manual guided me through this difficult process successfully. With fingers crossed I powered the MBP and - everything worked as it did many yours ago: The temperature is in the normal range 40-70°C with a fan speed of about 2000rpm and no noise anymore!
I'm glad I replaced the vintage thermal paste as well following the really excellent guide for replacing the heat pipe. This was more than originally planned, however, I got an almost new MBP in turn.