Overheating laptop

Hi, a friend just gave me his old Asus Z9200 laptop, and I'm having some problems with it overheating and shutting down. I blew out the heat sink fins and the fan, but it didn't help.
The guy who gave it to me said it's not uncommon for the manufacturer to forget to take off the protective film from the CPU, meaning it can't get a good connection with the heatsink. I'd like to look into that, but I don't know how to get the heatsink out. This is the first laptop I've ever owned.
I've looked for guides to disassembling the laptop, but have come up empty. Can anyone here walk me through the heatsink removal, please?

 

With the film I think they meant they forgot to the take cover off that protects the thermal paste. Thermal paste goes between the CPU and Heatsink to provide better cooling.

Can you take the plates off the bottom of the laptop?

 

I've taken the plate over the CPU/heat sink off, and inside there's an X shaped bracket holding the heatsink to the chip. I unscrewed the bracket, but I can't muve the heatsink. I don't see any other screws holding it down, though.

 

Okay here are some disassembly (the keyword for google) guides for Asus laptops:

http://repair4laptop.org/disassembly_asus.html

http://forum.notebookreview.com/showthread.php?t=158778

You may find the model here:

http://forum.notebookreview.com/forumdisplay.php?f=19

Often you can use these guides as "generic" references to complete the task, especially if you have several open on another computer so can you can look back at them.. I would suggest you look for the Asus models that look most similar and get tips from them to follow. You will want a decent TIM (Thermal Interface Material) to apply once you have it apart. Arctic Silver 5 is very good.

 

Using those guides, I was able to get the heatsink out. Seems the thermal paste was holding it to the CPU pretty tight. Didn't see any protective film that may have been left on, so I reapplied some paste and put it back on.
Also had a chance to clean the sink a bit more thoroughly. While it looked clean while it was installed, once I had it out I found that it was almost entirely blocked up.
The system seems to be running significantly cooler right now. A steady 52 degree when idle as opposed to the 80-something it was at before.

Thanks for the help

 

That is 52F or C? Ahhh it must be C so about 125F? Your lucky you didn't damage the CPU at 80C hopefully it will be fine now.