Fan isn't spinning
Hi, i'm new to 3d printing and i ran into a problem. One day the printer just stopped working (printing), it stopped feeding the plastic. I noticed that one of the fans wasn't spinning, so i took the head apart and just in case ordered a new fan and replaced the old one. I'm not sure if it's the hot end one or the part cooling one (or if i'm even using the right words), it's the one marked on the picture.
From reading the internet, i am under impression that the one marked on the picture should be spinning as soon as you turn the printer on (it doesn't even after replacement), and the other one is software controllable (it spins and does change the speed when i change the settings). Did i get it right? What do i do if it still doesn't spin?
Another thing is that the inside of the aluminum part through which the plastic goes is covered with goo. Is it normal? See the picture.
Thank you in advance for your help!