Loud screeching fan sound, fixable?

The fan sounds like a jet engine about to throw a fan. The screeching cry starts up as it powers up, then lowers and increases at a constant until shut down. It went out of warranty in Jan and I took it to a local repair shop to see what can be done. They tried to talk to Lenovo but was told this model is discontinued and they don’t have repair parts. So can the fan be disconnected and the laptop run ok? I have a cooling stand to assist with keeping the temp down.