Air Fan Dodge 318

I have a 89 dodge van, 318 motor, I noticed a rusted pipe for the
air-conditioning weeping air-conditioning fluid. Thinking I'm not worrying
about AC right now I will have it looked at later.

Now my air fan stopped working, I can do without the AC, but would like to
have the fan to circulate air.
Would the problem with the fan be related to the AC problem?
I can turn the fan to low or high and "I think" it might be slowly blowing
some air ...
Can someone refer me to a website that explains the 318 motor, with
diagrams. I know nothing about motors, but have to learn.