Is there a way to stop and start Macbook fans manually without reboot or sleep?

Macbook Pro 15" 2011 I've had Macs Fan Control for more than a year, and it spins my MB's fans at the max 5500-6000 rpm most of the time and I'm used to that noise because cooling is paramount. But yesterday one of the fans started to be extremely noisy. It makes a sound as if the blades were scraping against something. The odd thing is that the sound goes away for some time (returns seemingly at random) if I put MB to sleep or reboot it. But the sound will become worse if it appeared at ~6000 rpm and I set MFC to the lowest 2000 rpm. So the only way to stop fans from doing that annoying noise is to stop it completely and start back up. So the question is, is there a way to do it quickly or do I have to wait my MB to 'fall asleep' every time? p.s. I know that I should replace the fan, but I need some solution better than cmd+option+eject+wait until I do.