My Aspire 5570 2758 laptop gets hot and the fan isn't working.

When the fan stops you might be able to get some more life out of it with a good blast of compressed air. However, it is best to replace it because it is a critical component.

Taking apart a notebook is particularly challenging.
I recommend that you have a professional take care of this problem.
Aspire should have service center information on their website.

Okay, so you still want to do this yourself...

Use a digital camera and take a picture each time you remove a screw or part of the notebook.
Use a piece of paper and put your screws on it. Write the location that you removed the screw from on the paper next to it. This is a "screw map".
Try your best to find a diagram of your notebook on the Internet. You may not need it but it will sure makes things easier.
Search the Internet for a replacement fan. Ebay is a good source for notebook parts.
Make sure that you remove battery, AC adapter and hard drive first.
Set aside 3 or more hours and go for it. Be very, very patient. You can't be too careful.

Good Luck!

If this helps please vote for my solution.