Your welcome..
As far as the fan goes. I would replace the mini fuse holder with a in line stereo shop 30 amp glass fuse....
Second, I would check all grounds and Put an amp meter on it. Find out how many amps it draws during start up...
You may need to warranty the motor out, or up the fuse amps if it is surging over 30 amps when it starts. ALSO check the running amps. IF those are high, You have a bad wire, connection or motor..
The relay could also have a short in it....
Todd Z